@phdthesis{AlBaidhani2018,
  author    = {Al-Baidhani, Mohammed},
  title     = {Spectroscopy as a tool to investigate the high energy optical properties of nanostructured magnetically doped topological insulator},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-157221},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {In this dissertation the electronic and high-energy optical properties of thin nanoscale films of the magnetic topological insulator (MTI) (V,Cr)y(BixSb1-x)2-yTe3 are studied by means of X-ray photoelectron spectroscopy (XPS) and electron energy-loss spectroscopy (EELS). Magnetic topological insulators are presently of broad interest as the combination of ferromagnetism and spin-orbit coupling in these materials leads to a new topological phase, the quantum anomalous Hall state (QAHS), with dissipation less conduction channels. Determining and controlling the physical properties of these complex materials is therefore desirable for a fundamental understanding of the QAHS and for their possible application in spintronics. EELS can directly probe the electron energy-loss function of a material from which one can obtain the complex dynamic dielectric function by means of the Kramers-Kronig transformation and the Drude-Lindhard model of plasmon oscillations. The XPS core-level spectra in (V,Cr)y(BixSb1-x)2-yTe3 are analyzed in detail with regards to inelastic background contributions. It is shown that the spectra can be accurately described based on the electron energy-loss function obtained from an independent EELS measurement. This allows for a comprehensive and quantitative analysis of the XPS data, which will facilitate future core-level spectroscopy studies in this class of topological materials. From the EELS data, furthermore, the bulk and surface optical properties were estimated, and compared to ab initio calculations based on density functional theory (DFT) performed in the GW approximation for Sb2Te3. The experimental results show a good agreement with the calculated complex dielectric function and the calculated energy-loss function. The positions of the main plasmon modes reported here are expected to be generally similar in other materials in this class of nanoscale TI films. Hence, the present work introduces EELS as a powerful method to access the high-energy optical properties of TI thin films. Based on the presented results it will be interesting to explore more systematically the effects of stoichiometry, magnetic doping, film thickness and surface morphology on the electron-loss function, potentially leading to a better understanding of the complex interplay of structural, electronic, magnetic and optical properties in MTI nanostructures.},
  subject      = {Topologischer Isolator},
  language  = {en}
}
@phdthesis{Aulbach2018,
  author    = {Aulbach, Julian},
  title     = {Gold-Induced Atomic Wires on Terraced Silicon Surfaces: Formation and Interactions of Silicon Spin Chains},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-169347},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {Atomic nanowires formed by self-assembled growth on semiconducting surfaces represent a feasible physical realization of quasi-1D electron systems and can be used to study fascinating 1D quantum phenomena. The system in the focus of this thesis, Si(553)-Au, is generated by Au adsorption onto a stepped silicon surface. It features two different chain types, interspersed with each other: A Au chain on the terrace, and a honeycomb chain of graphitic silicon located at the step edge. The silicon atoms at the exposed edges of the latter are predicted to be spin-polarized and charge-ordered [1], leading to an ordered array of local magnetic moments referred to as ``spin chains''. The present thesis puts this spin chain proposal to an experimental test. A detailed scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) scrutiny reveals a distinct unoccupied density of states (DOS) feature localized at every third Si step-edge atom, which aligns perfectly with the density functional theory (DFT) prediction. This finding provides strong evidence for the formation of spin chains at the Si(553)-Au step edges, and simultaneously rules out the interpretation of previous studies which attributed the x3 step-edge superstructure to a Peierls instability. To study the formation of spin chains in further detail, an additional member of the so-called Si(hhk)-Au family -- Si(775)-Au -- is analyzed. Based on DFT modeling (performed by S.C. Erwin, Naval Research Laboratory, USA) and detailed STM and STS experiments, a new structure model for this surface is developed, and the absence of spin chains at the Si(775)-Au step edges is demonstrated. The different step-edge charge distributions of all known Si(hhk)-Au surfaces are traced back to an electron transfer between the terrace and the step edge. Accordingly, an unintentional structure defect should create a localized spin at the Si(775)-Au step edge. This prediction is verified experimentally, and suggest that surface chemistry can be used to create and destroy Si spin chains. Having clarified why spin chains form on some Si(hhk)-Au surfaces but not on others, various interaction effects of the Si(553)-Au spin chains are inspected. A collaborative analysis by SPA-LEED (M. Horn-von Hoegen group, University of Duisburg-Essen, Germany), DFT (S.C. Erwin), and STM reveals strong lateral coupling between adjacent spin chains, bearing interesting implications for their magnetic ordering. The centered geometry uncovered leads to magnetic frustration, and may stabilize a 2D quantum spin liquid. Moreover, a complex interplay between neighboring Au and Si chains is detected. Specifically, the interaction is found effectively ``one-way'', i.e., the Si step edges respond to the Au chains but not vice versa. This unidirectional effect breaks the parity of the Si chains, and creates two different configurations of step edges with opposite directionality. In addition to the static properties of the Si(553)-Au surface mentioned above, the occurrence of solitons in both wire types is witnessed in real space by means of high-resolution STM imaging. The solitons are found to interact with one another such that both move in a coupled fashion along the chains. Likewise, STM experiments as a function of the tunneling current suggest an excitation of solitons along the step edge by the STM tunneling tip. Solitons are also found to play an essential role in the temperature-dependent behavior of the Si(553)-Au step edges. It is an accepted fact that the distinct x3 superstructure of the Si(553)-Au step edges vanishes upon heating to room temperature. As a first step in exploring this transition in detail over a large temperature range, a previously undetected, occupied electronic state associated with the localized step-edge spins is identified by means of angle-resolved photoemission spectroscopy (ARPES). A tracking of this state as a function of temperature reveals an order-disorder-type transition. Complementary STM experiments attribute the origin of this transition to local, thermally activated spin site hops, which correspond to soliton-anitsoliton pairs. Finally, a manipulation of the Si(553)-Au atomic wire array is achieved by the stepwise adsorption of potassium atoms. This does not only increase the filling of the Au-induced surface bands culminating in a metal-insulator transition (MIT), but also modifies the Si step-edge charge distribution, as indicated by STM and ARPES experiments. [1] S. C. Erwin and F. Himpsel, Intrinsic magnetism at silicon surfaces, Nat. Commun. 1, 58 (2010).},
  subject      = {Rastertunnelmikroskopie},
  language  = {en}
}
@phdthesis{Balzer2018,
  author    = {Balzer, Christian},
  title     = {Adsorption-Induced Deformation of Nanoporous Materials — in-situ Dilatometry and Modeling},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-157145},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {The goal of this work is to improve the understanding of adsorption-induced deformation in nanoporous (and in particular microporous) materials in order to explore its potential for material characterization and provide guidelines for related technical applications such as adsorption-driven actuation. For this purpose this work combines in-situ dilatometry measurements with in-depth modeling of the obtained adsorption-induced strains. A major advantage with respect to previous studies is the combination of the dilatometric setup and a commercial sorption instrument resulting in high quality adsorption and strain isotherms. The considered model materials are (activated and thermally annealed) carbon xerogels, a sintered silica aerogel, a sintered hierarchical structured porous silica and binderless zeolites of type LTA and FAU; this selection covers micro-, meso- and macroporous as well as ordered and disordered model materials. All sample materials were characterized by scanning electron microscopy, gas adsorption and sound velocity measurements. In-situ dilatometry measurements on mesoporous model materials were performed for the adsorption of N2 at 77 K, while microporous model materials were also investigated for CO2 adsorption at 273 K, Ar adsorption at 77 K and H2O adsorption at 298 K. Within this work the available in-situ dilatometry setup was revised to improve resolution and reproducibility of measurements of small strains at low relative pressures, which are of particular relevance for microporous materials. The obtained experimental adsorption and strain isotherms of the hierarchical structured porous silica and a micro-macroporous carbon xerogel were quantitatively analyzed based on the adsorption stress model; this approach, originally proposed by Ravikovitch and Neimark, was extended for anisotropic pore geometries within this work. While the adsorption in silica mesopores could be well described by the classical and analytical theory of Derjaguin, Broekhoff and de Boer, the adsorption in carbon micropores required for comprehensive nonlocal density functional theory calculations. To connect adsorption-induced stresses and strains, furthermore mechanical models for the respective model materials were derived. The resulting theoretical framework of adsorption, adsorption stress and mechanical model was applied to the experimental data yielding structural and mechanical information about the model materials investigated, i.e., pore size or pore size distribution, respectively, and mechanical moduli of the porous matrix and the nonporous solid skeleton. The derived structural and mechanical properties of the model materials were found to be consistent with independent measurements and/or literature values. Noteworthy, the proposed extension of the adsorption stress model proved to be crucial for the correct description of the experimental data. Furthermore, it could be shown that the adsorption-induced deformation of disordered mesoporous aero-/xerogel structures follows qualitatively the same mechanisms obtained for the ordered hierarchical structured porous silica. However, respective quantitative modeling proved to be challenging due to the ill-shaped pore geometry of aero-/xerogels; good agreement between model and experiment could only be achieved for the filled pore regime of the adsorption isotherm and the relative pressure range of monolayer formation. In the intermediate regime of multilayer formation a more complex model than the one proposed here is required to correctly describe stress related to the curved adsorbate-adsorptive interface. Notably, for micro-mesoporous carbon xerogels it could be shown that micro- and mesopore related strain mechanisms superimpose one another. The strain isotherms of the zeolites were only qualitatively evaluated. The result for the FAU type zeolite is in good agreement with other experiments reported in literature and the theoretical understanding derived from the adsorption stress model. On the contrary, the strain isotherm of the LTA type zeolite is rather exceptional as it shows monotonic expansion over the whole relative pressure range. Qualitatively this type of strain isotherm can also be explained by the adsorption stress model, but a respective quantitative analysis is beyond the scope of this work. In summary, the analysis of the model materials' adsorption-induced strains proved to be a suitable tool to obtain information on their structural and mechanical properties including the stiffness of the nonporous solid skeleton. Investigations on the carbon xerogels modified by activation and thermal annealing revealed that adsorption-induced deformation is particularly suited to analyze even small changes of carbon micropore structures.},
  subject      = {Nanopor{\"o}ser Stoff},
  language  = {en}
}
@phdthesis{Bendias2018,
  author    = {Bendias, Michel Kalle},
  title     = {Quantum Spin Hall Effect - A new generation of microstructures},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-168214},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {The presented thesis summarizes the results from four and a half years of intense lithography development on (Cd,Hg)Te/HgTe/(Cd,Hg)Te quantum well structures. The effort was motivated by the unique properties of this topological insulator. Previous work from Molenkamp at al.\ has proven that the transport through such a 2D TI is carried by electrons with opposite spin, counter-propagating in 1D channels along the sample edge. However, up to this thesis, the length of quantized spin Hall channels has never been reported to exceed 4 µm. Therefore, the main focus was put on a reproducible and easy-to-handle fabrication process that reveals the intrinsic material parameters. Every single lithography step in macro as well as microscopic sample fabrication has been re-evaluated. In the Development, the process changes have been presented along SEM pictures, microgaphs and, whenever possible, measurement responses. We have proven the conventional ion milling etch method to damage the remaining mesa and result in drastically lower electron mobilities in samples of microscopic size. The novel KI:I2:HBr wet etch method for macro and microstructure mesa fabrication has been shown to leave the crystalline structure intact and result in unprecedented mobilities, as high as in macroscopic characterization Hall bars. Difficulties, such as an irregular etch start and slower etching of the conductive QW have been overcome by concentration, design and etch flow adaptations. In consideration of the diffusive regime, a frame around the EBL write field electrically decouples the structure mesa from the outside wafer. As the smallest structure, the frame is etched first and guarantees a non-different etching of the conductive layer during the redox reaction. A tube-pump method assures reproducible etch results with mesa heights below 300 nm. The PMMA etch mask is easy to strip and leaves a clean mesa with no redeposition. From the very first attempts, to the final etch process, the reader has been provided with the characteristics and design requirements necessary to enable the fabrication of nearly any mesa shape within an EBL write field of 200 µm. Magneto resistance measurement of feed-back samples have been presented along the development chronology of wet etch method and subsequent lithography steps. With increasing feature quality, more and more physics has been revealed enabling detailed evaluation of smallest disturbances. The following lithography improvements have been implemented. They represent a tool-box for high quality macro and microstructure fabrication on (CdHg)Te/HgTe of almost any kind. The optical positive resist ECI 3027 can be used as wet and as dry etch mask for structure sizes larger than 1 µm. It serves to etch mesa structures larger than the EBL write field. The double layer PMMA is used for ohmic contact fabrication within the EBL write field. Its thickness allows to first dry etch the (Cd,Hg)Te cap layer and then evaporate the AuGe contact, in situ and self-aligned. Because of an undercut, up to 300 nm can be metalized without any sidewalls after the lift-off. An edge channel mismatch within the contact leads can be avoided, if the ohmic contacts are designed to reach close to the sample and beneath the later gate electrode. The MIBK cleaning step prior to the gate application removes PMMA residuals and thereby improves gate and potential homogeneity. The novel low HfO2-ALD process enables insulator growth into optical and EBL lift-off masks of any resolvable shape. Directly metalized after the insulator growth, the self-aligned method results in thin and homogeneous gate electrode reproducibly withholding gate voltages to +-10 V. The optical negative resist ARN 4340 exhibits an undercut when developed. Usable as dry etch mask and lift-off resist, it enables an in-situ application of ohmic contacts first etching close to the QW, then metalizing AuGe. Up to 500 nm thickness, the undercut guarantees an a clean lift-off with no sidewalls. The undertaken efforts have led to micro Hall bar measurements with Hall plateaus and SdH-oszillations in up to now unseen levels of detail. The gap resistance of several micro Hall bars with a clear QSH signal have been presented in Quantum Spin Hall. The first to exhibit longitudinal resistances close to the expected h/2e2 since years, they reveal unprecedented details in features and characteristics. It has been shown that their protection against backscattering through time reversal symmetry is not as rigid as previously claimed. Values below and above 12.9 kΩ been explained, introducing backscattering within the Landauer-B{\"u}ttiker formalism of edge channel transport. Possible reasons have been discussed. Kondo, interaction and Rashba-backscattering arising from density inhomogeneities close to the edge are most plausible to explain features on and deviations from a quantized value. Interaction, tunneling and dephasing mechanisms as well as puddle size, density of states and Rashba Fields are gate voltage dependent. Therefore, features in the QSH signal are fingerprints of the characteristic potential landscape. Stable up to 11 K, two distinct but clear power laws have been found in the higher temperature dependence of the QSH in two samples. However, with ΔR = Tα, α = ¼ in one (QC0285) and α = 2 in the other (Q2745), none of the predicted dependencies could be confirmed. Whereas, the gap resistances of QC0285 remains QSH channel dominated up to 3.9 T and thereby confirmed the calculated lifting of the band inversion in magnetic field. The gate-dependent oscillating features in the QSH signal of Q2745 immediately increase in magnetic field. The distinct field dependencies allowed the assumption of two different dominant backscattering mechanisms. Resulting in undisturbed magneto transport and unprecedented QSH measurements The Novel Micro Hall Bar Process has proven to enable the fabrication of a new generation of microstructures.},
  subject      = {Quecksilbertellurid},
  language  = {en}
}
@article{ChinaBurrowsWangetal.2018,
  author    = {China, Swarup and Burrows, Susannah M. and Wang, Bingbing and Harder, Tristan H. and Weis, Johannes and Tanarhte, Meryem and Rizzo, Luciana V. and Brito, Joel and Cirino, Glauber G. and Ma, Po-Lun and Cliff, John and Artaxo, Paulo and Gilles, Mary K. and Laskin, Alexander},
  title     = {Fungal spores as a source of sodium salt particles in the Amazon basin},
  series = {Nature Communications},
  volume    = {9},
  journal   = {Nature Communications},
  doi       = {10.1038/s41467-018-07066-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-222492},
  year      = {2018},
  abstract  = {In the Amazon basin, particles containing mixed sodium salts are routinely observed and are attributed to marine aerosols transported from the Atlantic Ocean. Using chemical imaging analysis, we show that, during the wet season, fungal spores emitted by the forest biosphere contribute at least 30\% (by number) to sodium salt particles in the central Amazon basin. Hydration experiments indicate that sodium content in fungal spores governs their growth factors. Modeling results suggest that fungal spores account for ~69\% (31-95\%) of the total sodium mass during the wet season and that their fractional contribution increases during nighttime. Contrary to common assumptions that sodium-containing aerosols originate primarily from marine sources, our results suggest that locally-emitted fungal spores contribute substantially to the number and mass of coarse particles containing sodium. Hence, their role in cloud formation and contribution to salt cycles and the terrestrial ecosystem in the Amazon basin warrant further consideration.},
  language  = {en}
}
@article{DittmannBallesZabler2018,
  author    = {Dittmann, Jonas and Balles, Andreas and Zabler, Simon},
  title     = {Optimization based evaluation of grating interferometric phase stepping series and analysis of mechanical setup instabilities},
  series = {Journal of Imaging},
  volume    = {4},
  journal   = {Journal of Imaging},
  number    = {6},
  issn      = {2313-433X},
  doi       = {10.3390/jimaging4060077},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-197723},
  pages     = {77},
  year      = {2018},
  abstract  = {The diffraction contrast modalities accessible by X-ray grating interferometers are not imaged directly but have to be inferred from sine-like signal variations occurring in a series of images acquired at varying relative positions of the interferometer's gratings. The absolute spatial translations involved in the acquisition of these phase stepping series usually lie in the range of only a few hundred nanometers, wherefore positioning errors as small as 10 nm will already translate into signal uncertainties of 1-10\% in the final images if not accounted for. Classically, the relative grating positions in the phase stepping series are considered input parameters to the analysis and are, for the Fast Fourier Transform that is typically employed, required to be equidistantly distributed over multiples of the gratings' period. In the following, a fast converging optimization scheme is presented simultaneously determining the phase stepping curves' parameters as well as the actually performed motions of the stepped grating, including also erroneous rotational motions which are commonly neglected. While the correction of solely the translational errors along the stepping direction is found to be sufficient with regard to the reduction of image artifacts, the possibility to also detect minute rotations about all axes proves to be a valuable tool for system calibration and monitoring. The simplicity of the provided algorithm, in particular when only considering translational errors, makes it well suitable as a standard evaluation procedure also for large image series.},
  language  = {en}
}
@phdthesis{Grauer2018,
  author    = {Grauer, Stefan},
  title     = {Transport Phenomena in Bi\(_2\)Se\(_3\) and Related Compounds},
  publisher = {Verlag Dr. Hut GmbH},
  isbn      = {978-3-8439-3481-7},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-157666},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {One of the most significant technological advances in history was driven by the utilization of a new material class: semiconductors. Its most important application being the transistor, which is indispensable in our everyday life. The technological advance in the semiconductor industry, however, is about to slow down. Making transistors ever smaller to increase the performance and trying to reduce and deal with the dissipative heat will soon reach the limits dictated by quantum mechanics with Moore himself, predicting the death of his famous law in the next decade. A possible successor for semiconductor transistors is the recently discovered material class of topological insulators. A material which in its bulk is insulating but has topological protected metallic surface states or edge states at its boundary. Their electrical transport characteristics include forbidden backscattering and spin-momentum-locking with the spin of the electron being perpendicular to its momentum. Topological insulators therefore offer an opportunity for high performance devices with low dissipation, and applications in spintronic where data is stored and processed at the same point. The topological insulator Bi\(_2\)Se\(_3\) and related compounds offer relatively high energy band gaps and a rather simple band structure with a single dirac cone at the gamma point of the Brillouin zone. These characteritics make them ideal candidates to study the topological surface state in electrical transport experiments and explore its physics.},
  subject      = {Topologischer Isolator},
  language  = {en}
}
@phdthesis{Lutz2018,
  author    = {Lutz, Peter},
  title     = {Surface and Interface Electronic Structure in Ferroelectric BaTiO\(_3\)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159057},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {Transition metal oxides (TMO) represent a highly interesting material class as they exhibit a variety of different emergent phenomena including multiferroicity and superconductivity. These effects result from a significant interplay of charge, spin and orbital degrees of freedom within the correlated d-electrons. Oxygen vacancies (OV) at the surface of certain d0 TMO release free charge carriers and prompt the formation of a two-dimensional electron gas (2DEG). Barium titanate (BaTiO3) is a prototypical and promising d0 TMO. It displays ferroelectricity at room temperature and features several structural phase transitions, from cubic over tetragonal (at room temperature) and orthorhombic to rhombohedral. The spontaneous electric polarization in BaTiO3 can be used to manipulate the physical properties of adjacent materials, e.g. in thin films. Although the macroscopic properties of BaTiO3 are studied in great detail, the microscopic electronic structure at the surface and interface of BaTiO3 is not sufficiently understood yet due to the complex interplay of correlation within the d states, oxygen vacancies at the surface, ferroelectricity in the bulk and the structural phase transitions in BaTiO3. This thesis investigates the electronic structure of different BaTiO3 systems by means of angle-resolved photoelectron spectroscopy (ARPES). The valence band of BaTiO3 single crystals is systematically characterized and compared to theoretical band structure calculations. A finite p-d hybridization of titanium and oxygen states was inferred at the high binding energy side of the valence band. In BaTiO3 thin films, the occurrence of spectral weight near the Fermi level could be linked to a certain amount of OV at the surface which effectively dopes the host system. By a systematic study of the metallic surface states as a function of temperature and partial oxygen pressure, a model was established which reflects the depletion and accumulation of charge carriers at the surface of BaTiO3. An instability at T ~ 285K assumes a volatile behavior of these surface states. The ferroelectricity in BaTiO3 allows a control of the electronic structure at the interface of BaTiO3-based heterostructures. Therefore, the interface electronic structure of Bi/BaTiO3 was studied with respect to the strongly spin-orit coupled states in Bi by also including a thickness dependent characterization. The ARPES results, indeed, confirm the presence of Rashba spin-split electronic states in the bulk band gap of the ferroelectric substrate. By varying the film thickness in Bi/BaTiO3, it was able to modify the energy position and the Fermi vector of the spin-split states. This observation is associated with the appearance of an interface state which was observed for very low film thickness. Both spectral findings suggest a significant coupling between the Bi films and BaTiO3.},
  subject      = {Bariumtitanat},
  language  = {en}
}
@phdthesis{Munz2018,
  author    = {Munz, Eberhard},
  title     = {Physiological and metabolical high-resolution MRI of plants},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-172518},
  school      = {Universit{\"a}t W{\"u}rzburg},
  pages     = {177},
  year      = {2018},
  abstract  = {The noninvasive magnetic resonance imaging technique allows for the investigation of functional processes in the living plant. For this purpose during this work, different NMR imaging methods were further developed and applied. For the localisation of the intrusion of water into the germinating rape seed with the simultaneous depiction of the lipid-rich tissue via a 3D rendering, in Chap. 5 the technique of interleaved chemical selective acquisition of water and lipid was used in the germinating seed. The utilization of high-resolution MR images of germinated seeds enabled the localization of a predetermined water gap in the lipid-rich aleurone layer, which resides directly under the seed coat. The for a long time in biology prevalent discussion, whether such a gap exists or the seed soaks up the water from all sides, rather like a sponge, could hereby, at least for the rapeseed seed, be answered clearly. Furthermore, the segmentation and 3D visualization of the vascular tissue in the rapeseed seeds was enabled by the high-resolution datasets, a multiply branched structure preconstructed in the seed could be shown. The water is directed by the vascular tissue and thus awakens the seed gradually to life. This re-awakening could as well be tracked by means of invasive imaging via an oxygen sensor. In the re-awakened seeds, the lipid degradation starts, other than expected, not in the lipid-rich cotyledons but in the residual endosperm remaining from seed development and in the aleurone layer which previously protected the embryo. Within this layer, the degradation could be verified in the high-resolution MR datasets. The method presented in Chap. 6 provides a further characteristic trait for phenotyping of seeds and lipid containing plants in general. The visualization of the compounds of fatty acids in plant seeds and fruits could be achieved by the distinct utilization of chemical shift-selective imaging techniques. Via the application of a CSI sequence the fatty acid compounds in an olive were localized in a 2D slice. In conjunction with an individually adjusted CHESS presaturation module Haa85 the high-resolution 3D visualization of saturated and unsaturated fatty acid compounds in different seeds was achieved. The ratio maps calculated from these datasets allow to draw conclusions from the developmental stage or the type of seed. Furthermore, it could be shown that the storage condition of two soybean seeds with different storage time durations lead to no degradation of the fatty acid content. Additional structural information from inside of dry seeds are now accessible via MRI. In this work the imaging of cereal seeds could be significantly improved by the application of the UTE sequence. The hitherto existing depictions of the lipid distribution, acquired with the spin echo sequence, were always sufficient for examinations of the lipid content, yet defects in the starchy endosperm or differences in the starch concentration within the seed remained constantly unseen with this technique. In a direct comparison of the datasets acquired with the previous imaging technique (spin echo) and with UTE imaging, the advantage of data acquisition with UTE could be shown. By investigating the potential seed compounds (starch, proteins, sugar) in pure form, the constituent parts contributing to the signal could be identified as bound water (residual moisture) and starch. The application of a bi-exponential fit on the datasets of the barley seed enabled the separate mapping of magnetization and of relaxation time of two components contributing to the NMR signal. The direct comparison with histological stainings verified the previous results, thus this technique can be used for the selective imaging of starch in dry seeds. Conclusions on the translocation characteristics in plants can be drawn by the technique proposed in Chap. 8. The associated translocation velocities can now, even in the range of several um/h, be determined in the living plant. Based on calculated concentrations of an MR contrast agent, which was taken up by the plant, these translocation velocities were estimated both in longitudinal direction, thus along the vascular bundle, and in horizontal direction, thus out of the bundle. The latter velocity is located below the contrast agent's velocity value of free diffusion. By adjusting a dynamic contrast-enhancing imaging technique (DCE-Imaging, Tof91) the acquisition duration of a T1-map was significantly reduced. By means of these maps, local concentrations of the contrast agent in plant stems and the siliques of the rapeseed plant could be determined. Numerous questions in plant science can only be answered by non-invasive techniques such as MRI. For this reason, besides the experimental results achieved in this work, further NMR methods were tested and provided for the investigation of plants. As an example, the study on the imaging of magnetic exchange processes are mentioned, which provided the groundwork for a possible transfer of CEST experiments (Chemical Exchange Saturation Transfer) to the plant. The results are presented in the bachelor thesis of A. J{\"a}ger Jae17, which was performed under my supervision, they find great interest under biologists. The development of new technologies, which extend the possibilities for the investigation of living organisms, is of great importance. For this reason, I have contributed to the development of the currently unpublished method RACETE (Refocused Acquisition of Chemical Exchange Transferred Excitations [Jak17, Reu17, Gut18a]). By rephasing the transferred magnetization the utilization of properties which have not been available in chemical "`exchange"' experiments is enabled. With this method a positive contrast is generated, thus a reference experiment is not mandatory. Furthermore, the image phase, which in classical experiments contains no information about the exchanged protons, can be used for the distinct identification of multiple substances which have been excited simultaneously. This recently at the Department of Experimental Physics V developed method can be used in particular for the identification of lipids and for the localization of sugars and amino acids, thus it can serve the enhancement and improvement of non-invasive analytical methods.},
  subject      = {Kernspintomografie},
  language  = {en}
}
@phdthesis{PonceGarcia2018,
  author    = {Ponce Garcia, Irene Paola},
  title     = {Strategies for optimizing dynamic MRI},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-162622},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {In Magnetic Resonance Imaging (MRI), acquisition of dynamic data may be highly complex due to rapid changes occurred in the object to be imaged. For clinical diagnostic, dynamic MR images require both high spatial and temporal resolution. The speed in the acquisition is a crucial factor to capture optimally dynamics of the objects to obtain accurate diagnosis. In the 90's, partially parallel MRI (pMRI) has been introduced to shorten scan times reducing the amount of acquired data. These approaches use multi-receiver coil arrays to acquire independently and simultaneously the data. Reduction in the amount of acquired data results in images with aliasing artifacts. Dedicated methods as such Sensitivity Encoding (SENSE) and Generalized Autocalibrating Partially Parallel Acquisition (GRAPPA) were the basis of a series of algorithms in pMRI. Nevertheless, pMRI methods require extra spatial or temporal information in order to optimally reconstruct the data. This information is typically obtained by an extra scan or embedded in the accelerated acquisition applying a variable density acquisition scheme. In this work, we were able to reduce or totally eliminate the acquisition of the training data for kt-SENSE and kt-PCA algorithms obtaining accurate reconstructions with high temporal fidelity. For dynamic data acquired in an interleaved fashion, the temporal average of accelerated data can generate an artifact-free image used to estimate the coil sensitivity maps avoiding the need of extra acquisitions. However, this temporal average contains errors from aliased components, which may lead to signal nulls along the spectra of reconstructions when methods like kt-SENSE are applied. The use of a GRAPPA filter applied to the temporal average reduces these errors and subsequently may reduce the null components in the reconstructed data. In this thesis the effect of using temporal averages from radial data was investigated. Non-periodic artifacts performed by undersampling radial data allow a more accurate estimation of the true temporal average and thereby avoiding undesirable temporal filtering in the reconstructed images. kt-SENSE exploits not only spatial coil sensitivity variations but also makes use of spatio-temporal correlations in order to separate the aliased signals. Spatio-temporal correlations in kt-SENSE are learnt using a training data set, which consists of several central k-space lines acquired in a separate scan. The scan of these extra lines results in longer acquisition times even for low resolution images. It was demonstrate that limited spatial resolution of training data set may lead to temporal filtering effects (or temporal blurring) in the reconstructed data. In this thesis, the auto-calibration for kt-SENSE was proposed and its feasibility was tested in order to completely eliminate the acquisition of training data. The application of a prior TSENSE reconstruction produces the training data set for the kt-SENSE algorithm. These training data have full spatial resolution. Furthermore, it was demonstrated that the proposed auto-calibrating method reduces significantly temporal filtering in the reconstructed images compared to conventional kt-SENSE reconstructions employing low resolution training images. However, the performance of auto-calibrating kt-SENSE is affected by the Signal-to-Noise Ratio (SNR) of the first pass reconstructions that propagates to the final reconstructions. Another dedicated method used in dynamic MRI applications is kt-PCA, that was first proposed for the reconstruction of MR cardiac data. In this thesis, kt-PCA was employed for the generation of spatially resolved M0, T1 and T2 maps from a single accelerated IRTrueFISP or IR-Snapshot FLASH measurement. In contrast to cardiac dynamic data, MR relaxometry experiments exhibit signal at all temporal frequencies, which makes their reconstruction more challenging. However, since relaxometry measurements can be represented by only few parameters, the use of few principal components (PC) in the kt-PCA algorithm can significantly simplify the reconstruction. Furthermore, it was found that due to high redundancy in relaxometry data, PCA can efficiently extract the required information from just a single line of training data. It has been demonstrated in this thesis that auto-calibrating kt-SENSE is able to obtain high temporal fidelity dynamic cardiac reconstructions from moderate accelerated data avoiding the extra acquisition of training data. Additionally, kt-PCA has been proved to be a suitable method for the reconstruction of highly accelerated MR relaxometry data. Furthermore, a single central training line is necessary to obtain accurate reconstructions. Both reconstruction methods are promising for the optimization of training data acquisition and seem to be feasible for several clinical applications.},
  subject      = {Kernspintomografie},
  language  = {en}
}
@phdthesis{Razinskas2018,
  author    = {Razinskas, Gary},
  title     = {Functional plasmonic nanocircuitry},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166917},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {In this work, functional plasmonic nanocircuitry is examined as a key of revolutionizing state-of-the-art electronic and photonic circuitry in terms of integration density and transmission bandwidth. In this context, numerical simulations enable the design of dedicated devices, which allow fundamental control of photon flow at the nanometer scale via single or multiple plasmonic eigenmodes. The deterministic synthesis and in situ analysis of these eigenmodes is demonstrated and constitutes an indispensable requirement for the practical use of any device. By exploiting the existence of multiple eigenmodes and coherence - both not accessible in classical electronics - a nanoscale directional coupler for the ultrafast spatial and spatiotemporal coherent control of plasmon propagation is conceived. Future widespread application of plasmonic nanocircuitry in quantum technologies is boosted by the promising demonstrations of spin-optical and quantum plasmonic nanocircuitry.},
  subject      = {Nanooptik},
  language  = {en}
}
@article{RazinskasBiagioniHecht2018,
  author    = {Razinskas, Gary and Biagioni, Paolo and Hecht, Bert},
  title     = {Limits of Kirchhoff's laws in plasmonics},
  series = {Scientific Reports},
  volume    = {8},
  journal   = {Scientific Reports},
  number    = {1921},
  doi       = {10.1038/s41598-018-20239-x},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176080},
  year      = {2018},
  abstract  = {The validity of Kirchhoff's laws in plasmonic nanocircuitry is investigated by studying a junction of plasmonic two-wire transmission lines. We find that Kirchhoff's laws are valid for sufficiently small values of a phenomenological parameter κ relating the geometrical parameters of the transmission line with the effective wavelength of the guided mode. Beyond such regime, for large values of the phenomenological parameter, increasing deviations occur and the equivalent impedance description (Kirchhoff's laws) can only provide rough, but nevertheless useful, guidelines for the design of more complex plasmonic circuitry. As an example we investigate a system composed of a two-wire transmission line and a nanoantenna as the load. By addition of a parallel stub designed according to Kirchhoff's laws we achieve maximum signal transfer to the nanoantenna.},
  language  = {en}
}
@article{RoedingBrixner2018,
  author    = {Roeding, Sebastian and Brixner, Tobias},
  title     = {Coherent two-dimensional electronic mass spectrometry},
  series = {Nature Communications},
  volume    = {9},
  journal   = {Nature Communications},
  number    = {2519},
  doi       = {10.1038/s41467-018-04927-w},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226458},
  pages     = {1-9},
  year      = {2018},
  abstract  = {Coherent two-dimensional (2D) optical spectroscopy has revolutionized our ability to probe many types of couplings and ultrafast dynamics in complex quantum systems. The dynamics and function of any quantum system strongly depend on couplings to the environment. Thus, studying coherent interactions for different environments remains a topic of tremendous interest. Here we introduce coherent 2D electronic mass spectrometry that allows 2D measurements on effusive molecular beams and thus on quantum systems with minimum system-bath interaction and employ this to identify the major ionization pathway of 3d Rydberg states in NO2. Furthermore, we present 2D spectra of multiphoton ionization, disclosing distinct differences in the nonlinear response functions leading to the ionization products. We also realize the equivalent of spectrally resolved transient-absorption measurements without the necessity for acquiring weak absorption changes. Using time-of-flight detection introduces cations as an observable, enabling the 2D spectroscopic study on isolated systems of photophysical and photochemical reactions.},
  language  = {en}
}
@phdthesis{Sidiropoulou2018,
  author    = {Sidiropoulou, Ourania},
  title     = {Characterization of the ATLAS-type Micromegas Detectors},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167323},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {Micromegas are parallel-plate gaseous detectors with micro-pattern readout structures that are able to measure precisely and efficiently at high particle rates. Their difference with respect to other gaseous detectors is that the space in which particles ionise the gas and create electrons is separated from the region in which these electrons are multiplied (or amplified) by a thin metallic mesh. In the ionisation region, typically a few mm thick, a moderate field of a few hundred V/cm is applied. The amplification region with a homogeneous electrical field of 40--50~kV/cm is only 100--150~\$\upmu\$m thick. The latter guarantees that the positive ions produced in the amplification process are rapidly evacuated and the possibility to build up space charge at high rate is reduced. Critical in micromegas detectors are sparks in the thin amplification region in the presence of the high electrical field. This problem was solved in 2011 by introducing a spark protection scheme. It consists of a layer of resistive strips on top of the readout strips, separated from the latter by a thin insulation layer. Micromegas with the spark protection scheme were selected as instrumentation of the first ATLAS forward muon station (NSW) in the upgrade of the ATLAS detector for the operation of the Large Hadron Collider (LHC) at high luminosity (HL-LHC), expected for 2026. The main subjects of this thesis are: the characterisation of the first micromegas quadruplet prototypes for the NSW detectors; the characterisation of the materials used in the spark-protection system; and the study of the influence of the mesh distance holders (pillars) on the detector performance. The thesis starts with a brief introduction into the LHC and ATLAS projects, followed by a chapter that explains the reason for the upgrade of the ATLAS muon system and shows the layout of the NSW. The first of the three main chapters covers the construction and the characterisation of the first two prototypes for the NSW detectors. These detectors comprise four detection layers and have the same mechanical structure as the NSW detectors. The mechanical precision as well as the homogeneity of the detector response are discussed. The latter has been measured using X-rays and cosmic rays. The spatial resolution that can be achieved with these detectors precision has been measured at the MAMI accelerator at Mainz with low-energy electrons. The chapter is completed by a section that describes the successful integration of a data acquisition system (DAQ) into the official ATLAS DAQ system that was required for an initially planned installation of one of the prototypes on the existing Small Wheel. The next chapter presents a study of the influence of temperature and humidity changes on the resistive strips used in the spark protection system. In addition the long-term stability of the resistive material has been measured accumulating charge equivalent to 100 years of operation in the HL-LHC and exposing the samples to intense gamma irradiation equivalent to 10 years of HL-LHC operation. The third part covers the impact of the mesh distance holders (pillars) on the performance of the detector. This study has been performed with a 10 x 10 cm\$^2\$ bulk-micromegas with two different pillar shapes. Both 5.9 keV gammas from a \$^{55}\$Fe and 8 keV X-rays from a Cu target were used. In this context also the electrostatic charge-up of the detector is discussed. In the Appendices one finds a summary of the fundamental physics relevant for gaseous detectors as well as some supporting material for the topics covered in the main part of the thesis.},
  subject      = {ATLAS <Teilchendetektor>},
  language  = {en}
}
@phdthesis{Wiedenmann2018,
  author    = {Wiedenmann, Jonas},
  title     = {Induced topological superconductivity in HgTe based nanostructures},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-162782},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {This thesis describes the studies of topological superconductivity, which is predicted to emerge when pair correlations are induced into the surface states of 2D and 3D topolog- ical insulators (TIs). In this regard, experiments have been designed to investigate the theoretical ideas first pioneered by Fu and Kane that in such system Majorana bound states occur at vortices or edges of the system [Phys. Rev. Lett. 100, 096407 (2008), Phys. Rev. B 79, 161408 (2009)]. These states are of great interest as they constitute a new quasiparticle which is its own antiparticle and can be used as building blocks for fault tolerant topological quantum computing. After an introduction in chapter 1, chapter 2 of the thesis lays the foundation for the understanding of the field of topology in the context of condensed matter physics with a focus on topological band insulators and topological superconductors. Starting from a Chern insulator, the concepts of topological band theory and the bulk boundary corre- spondence are explained. It is then shown that the low energy Hamiltonian of mercury telluride (HgTe) quantum wells of an appropriate thickness can be written as two time reversal symmetric copies of a Chern insulator. This leads to the quantum spin Hall effect. In such a system, spin-polarized one dimensional conducting states form at the edges of the material, while the bulk is insulating. This concept is extended to 3D topological insulators with conducting 2D surface states. As a preliminary step to treating topological superconductivity, a short review of the microscopic theory of superconductivity, i.e. the theory of Bardeen, Cooper, and Shrieffer (BCS theory) is presented. The presence of Majorana end modes in a one dimensional superconducting chain is explained using the Kitaev model. Finally, topological band insulators and conventional superconductivity are combined to effectively engineer p-wave superconductivity. One way to investigate these states is by measuring the periodicity of the phase of the Josephson supercurrent in a topological Josephson junction. The signature is a 4π-periodicity compared to the 2π-periodicity in conventional Josephson junctions. The proof of the presence of this effect in HgTe based Josephson junction is the main goal of this thesis and is discussed in chapters 3 to 6. Chapter 3 describes in detail the transport of a 3D topological insulator based weak link under radio-frequency radiation. The chapter starts with a review of the state of research of (i) strained HgTe as 3D topological insulator and (ii) the progress of induc- ing superconducting correlations into the topological surface states and the theoretical predictions of 3D TI based Josephson junctions. Josephson junctions based on strained HgTe are successfully fabricated. Before studying the ac driven Josephson junctions, the dc transport of the devices is analysed. The critical current as a function of temperature is measured and it is possible to determine the induced superconducting gap. Under rf illumination Shapiro steps form in the current voltage characteristic. A missing first step at low frequencies and low powers is found in our devices. This is a signature of a 4π-periodic supercurrent. By studying the device in a wide parameter range - as a 147148 SUMMARY function of frequency, power, device geometry and magnetic field - it is shown that the results are in agreement with the presence of a single gapless Andreev doublet and several conventional modes. Chapter 4 gives results of the numerical modelling of the I -V dynamics in a Josephson junction where both a 2π- and a 4π-periodic supercurrents are present. This is done in the framework of an equivalent circuit representation, namely the resistively shunted Josephson junction model (RSJ-model). The numerical modelling is in agreement with the experimental results in chapter 3. First, the missing of odd Shapiro steps can be understood by a small 4π-periodic supercurrent contribution and a large number of modes which have a conventional 2π-periodicity. Second, the missing of odd Shapiro steps occurs at low frequency and low rf power. Third, it is shown that stochastic processes like Landau Zener tunnelling are most probably not responsible for the 4π contribution. In a next step the periodicity of Josephson junctions based on quantum spin Hall insulators using are investigated in chapter 5. A fabrication process of Josephson junctions based on inverted HgTe quantum wells was successfully developed. In order to achieve a good proximity effect the barrier material was removed and the superconductor deposited without exposing the structure to air. In a next step a gate electrode was fabricated which allows the chemical potential of the quantum well to be tuned. The measurement of the diffraction pattern of the critical current Ic due to a magnetic field applied perpendicular to the sample plane was conducted. In the vicinity to the expected quantum spin Hall phase, the pattern resembles that of a superconducting quantum interference device (SQUID). This shows that the current flows predominantly on the edges of the mesa. This observation is taken as a proof of the presence of edge currents. By irradiating the sample with rf, missing odd Shapiro steps up to step index n = 9 have been observed. This evidences the presence of a 4π-periodic contribution to the supercurrent. The experiment is repeated using a weak link based on a non-inverted HgTe quantum well. This material is expected to be a normal band insulator without helical edge channels. In this device, all the expected Shapiro steps are observed even at low frequencies and over the whole gate voltage range. This shows that the observed phenomena are directly connected to the topological band structure. Both features, namely the missing of odd Shapiro steps and the SQUID like diffraction pattern, appear strongest towards the quantum spin Hall regime, and thus provide evidence for induced topological superconductivity in the helical edge states. A more direct way to probe the periodicity of the Josephson supercurrent than using Shapiro steps is the measurement of the emitted radiation of a weak link. This experiment is presented in chapter 6. A conventional Josephson junction converts a dc bias V to an ac current with a characteristic Josephson frequency fJ = eV /h. In a topological Josephson junction a frequency at half the Josephson frequency fJ /2 is expected. A new measurement setup was developed in order to measure the emitted spectrum of a single Josephson junction. With this setup the spectrum of a HgTe quantum well based Josephson junction was measured and the emission at half the Josephson frequency fJ /2 was detected. In addition, fJ emission is also detected depending on the gate voltage and detection frequency. The spectrum is again dominated by half the Josephson emission at low voltages while the conventional emission is determines the spectrum at high voltages. A non-inverted quantum well shows only conventional emission over the whole gateSUMMARY 149 voltage and frequency range. The linewidth of the detected frequencies gives a measure on the lifetime of the bound states: From there, a coherence time of 0.3-4ns for the fJ /2 line has been deduced. This is generally shorter than for the fJ line (3-4ns). The last part of the thesis, chapter 7, reports on the induced superconducting state in a strained HgTe layer investigated by point-contact Andreev reflection spectroscopy. For the experiment, a HgTe mesa was fabricated with a small constriction. The diameter of the orifice was chosen to be smaller than the mean free path estimated from magne- totransport measurements. Thus one gets a ballistic point-contact which allows energy resolved spectroscopy. One part of the mesa is covered with a superconductor which induces superconducting correlations into the surface states of the topological insulator. This experiment therefore probes a single superconductor normal interface. In contrast to the Josephson junctions studied previously, the geometry allows the acquisition of energy resolved information of the induced superconducting state through the measurement of the differential conductance dI/dV as a function of applied dc bias for various gate voltages, temperatures and magnetic fields. An induced superconducting order parame- ter of about 70µeV was extracted but also signatures of the niobium gap at the expected value around Δ Nb ≈ 1.1meV have been found. Simulations using the theory developed by Blonder, Tinkham and Klapwijk and an extended model taking the topological surface states into account were used to fit the data. The simulations are in agreement with a small barrier at the topological insulator-induced topological superconductor interface and a high barrier at the Nb to topological insulator interface. To understand the full con- ductance curve as a function of applied voltage, a non-equilibrium driven transformation is suggested. The induced superconductivity is suppressed at a certain bias value due to local electron population. In accordance with this suppression, the relevant scattering regions change spatially as a function of applied bias. To conclude, it is emphasized that the experiments conducted in this thesis found clear signatures of induced topological superconductivity in HgTe based quantum well and bulk devices and opens up the avenue to many experiments. It would be interesting to apply the developed concepts to other topological matter-superconductor hybrid systems. The direct spectroscopy and manipulation of the Andreev bound states using circuit quantum electrodynamic techniques should be the next steps for HgTe based samples. This was already achieved in superconducting atomic break junctions by the group in Saclay [Science 2015, 349, 1199-1202 (2015)]. Another possible development would be the on-chip detection of the emitted spectrum as a function of the phase φ through the junction. In this connection, the topological junction needs to be shunted by a parallel ancillary junction. Such a setup would allow the current phase relation I(φ) directly and the lifetime of the bound states to be measured directly. By coupling this system to a spectrometer, which can be another Josephson junction, the energy dependence of the Andreev bound states E(φ) could be obtained. The experiments on the Andreev reflection spectroscopy described in this thesis could easily be extended to two dimensional topological insulators and to more complex geometries, like a phase bias loop or a tunable barrier at the point-contact. This work might also be useful for answering the question how and why Majorana bound states can be localized in quantum spin Hall systems.},
  subject      = {Quecksilbertellurid},
  language  = {en}
}
@article{OPUS4-22072,
  title     = {Search for Higgs boson decays to beyond-the-Standard-Model light bosons in four-lepton events with the ATLAS detector at root s=13 TeV},
  series = {Journal of High Energy Physics},
  volume    = {166},
  journal   = {Journal of High Energy Physics},
  number    = {6},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP06(2018)166},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220721},
  pages     = {1-50},
  year      = {2018},
  abstract  = {A search is conducted for a beyond-the-Standard-Model boson using events where a Higgs boson with mass 125 GeV decays to four leptons (l = e or mu). This decay is presumed to occur via an intermediate state which contains one or two on-shell, promptly decaying bosons: H -> ZX/XX -> 4l , where X is a new vector boson Z(d) or pseudoscalar a with mass between 1 and 60 GeV. The search uses pp collision data collected with the ATLAS detector at the LHC with an integrated luminosity of 36.1 fb(-1) at a centre-of-mass energy root s = 13TeV. No significant excess of events above Standard Model background predictions is observed; therefore, upper limits at 95\% confidence level are set on model-independent fiducial cross-sections, and on the Higgs boson decay branching ratios to vector and pseudoscalar bosons in two benchmark models.},
  language  = {en}
}
@article{OPUS4-22578,
  title     = {Search for diboson resonances with boson-tagged jets in \({pp}\) collisions at root S=13 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {777},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2017.12.011},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225782},
  pages     = {91-113},
  year      = {2018},
  abstract  = {Narrow resonances decaying into WW, WZ or ZZ boson pairs are searched for in 36.7 fb(-1) of proton-proton collision data at a centre-of-mass energy of root s = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The diboson system is reconstructed using pairs of large-radius jets with high transverse momentum and tagged as compatible with the hadronic decay of high-momentum Wor Zbosons, using jet mass and substructure properties. The search is sensitive to diboson resonances with masses in the range 1.2-5.0 TeV. No significant excess is observed in any signal region. Exclusion limits are set at the 95\% confidence level on the production cross section times branching ratio to dibosons for a range of theories beyond the Standard Model. Model-dependent lower limits on the mass of new gauge bosons are set, with the highest limit set at 3.5 TeV in the context of mass-degenerate resonances that couple predominantly to bosons. (c) 2017 The Author(s). Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22540,
  title     = {Measurement of the production cross-section of a single top quark in association with a \(Z\) boson in proton-proton collisions at 13 TeV with the ATLAS detector},
  series = {Physics letters B},
  volume    = {780},
  journal   = {Physics letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.03.023},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225406},
  pages     = {557-577},
  year      = {2018},
  abstract  = {The production of a top quark in association with a Z boson is investigated. The proton-proton collision data collected by the ATLAS experiment at the LHC in 2015 and 2016 at a centre-of-mass energy of root s = 13 TeV are used, corresponding to an integrated luminosity of 36.1 fb(-1). Events containing three identified leptons (electrons and/or muons) and two jets, one of which is identified as a b-quark jet are selected. The major backgrounds are diboson, tt(\$)over-bar and Z + jets production. A neural network is used to improve the background rejection and extract the signal. The resulting significance is 4.2 sigma in the data and the expected significance is 5.4 sigma. The measured cross-section for tZq production is 600 +/- 170(stat.)+/- 140(syst.)fb. (C) 2018 The Author(s). Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22543,
  title     = {A search for resonances decaying into a Higgs boson and a new particle \(X\) in the \({XH}\) -> \({qqbb}\) final state with the ATLAS detector},
  series = {Physics letters B},
  volume    = {779},
  journal   = {Physics letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.01.042},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225435},
  pages     = {24-45},
  year      = {2018},
  abstract  = {A search for heavy resonances decaying into a Higgs boson (H) and a new particle (X) is reported, utilizing 36.1 fb(-1) of proton-proton collision data at root s = 13 TeV collected during 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. The particle Xis assumed to decay to a pair of light quarks, and the fully hadronic final state XH -> q (q) over bar 'b (b) over bar is analysed. The search considers the regime of high XH resonance masses, where the X and H bosons are both highly Lorentz-boosted and are each reconstructed using a single jet with large radius parameter. A two-dimensional phase space of XH mass versus X mass is scanned for evidence of a signal, over a range of XH resonance mass values between 1 TeV and 4 TeV, and for X particles with masses from 50 GeV to 1000 GeV. All search results are consistent with the expectations for the background due to Standard Model processes, and 95\% CL upper limits are set, as a function of XH and X masses, on the production cross-section of the XH -> q (q) over bar 'b (b) over bar resonance. (c) 2018 The Author(s). Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22594,
  title     = {Search for an invisibly decaying Higgs boson or dark matter candidates produced in association with a Z boson in \({pp}\) collisions at root s=13 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {776},
  journal   = {Physics Letters B},
  number    = {1},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2017.11.049},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225947},
  pages     = {318-337},
  year      = {2018},
  abstract  = {A search for an invisibly decaying Higgs boson or dark matter candidates produced in association with a leptonically decaying Z boson in proton-proton collisions at root s = 13 TeV is presented. This search uses 36.1 fb(-1) of data collected by the ATLAS experiment at the Large Hadron Collider. No significant deviation from the expectation of the Standard Model backgrounds is observed. Assuming the Standard Model ZH production cross-section, an observed (expected) upper limit of 67\% (39\%) at the 95\% confidence level is set on the branching ratio of invisible decays of the Higgs boson with mass m(H) = 125 GeV. The corresponding limits on the production cross-section of the ZH process with the invisible Higgs boson decays are also presented. Furthermore, exclusion limits on the dark matter candidate and mediator masses are reported in the framework of simplified dark matter models. (c) 2017 The Author(s). Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22544,
  title     = {Search for heavy resonances decaying into a W or Z boson and a Higgs boson in final states with leptons and b-jets in 36 fb\(^{-1}\) of root s=13 TeV pp collisions with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {174},
  journal   = {Journal of High Energy Physics},
  number    = {3},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP03(2018)174},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225446},
  pages     = {1-52},
  year      = {2018},
  abstract  = {A search is conducted for new resonances decaying into a W or Z boson and a 125 GeV Higgs boson in the nu(nu) over barb (b) over bar, l(+/-)nu b (b) over bar, and l(+)l(-)b (b) over bar final states, where l(+/-) = e(+/-) or mu(+/-), in pp collisions at root s = 13 TeV. The data used correspond to a total integrated luminosity of 36.1 fb(-1) collected with the ATLAS detector at the Large Hadron Collider during the 2015 and 2016 data-taking periods. The search is conducted by examining the reconstructed invariant or transverse mass distributions of Wh and Zh candidates for evidence of a localised excess in the mass range of 220 GeV up to 5 TeV. No significant excess is observed and the results are interpreted in terms of constraints on the production cross-section times branching fraction of heavy W' and Z' resonances in heavy-vector-triplet models and the CP-odd scalar boson A in two-Higgs-doublet models. Upper limits are placed at the 95\% confidence level and range between 9.0 x 10(-4) pb and 7.3 x 10(-1) pb depending on the model and mass of the resonance.},
  language  = {en}
}
@article{OPUS4-22070,
  title     = {Search for supersymmetry in events with four or more leptons in root s=13 TeV \({pp}\) collisions with ATLAS},
  series = {Physical Review D},
  volume    = {98},
  journal   = {Physical Review D},
  number    = {3},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.98.032009},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220705},
  pages     = {1-31},
  year      = {2018},
  abstract  = {Results from a search for supersymmetry in events with four or more charged leptons (electrons, muons and taus) are presented. The analysis uses a data sample corresponding to 36.1 fb(-1) of proton-proton collisions delivered by the Large Hadron Collider at root s = 13 TeV and recorded by the ATLAS detector. Four-lepton signal regions with up to two hadronically decaying taus are designed to target a range of supersymmetric scenarios that can be either enriched in or depleted of events involving the production and decay of a Z boson. Data yields are consistent with Standard Model expectations and results are used to set upper limits on the event yields from processes beyond the Standard Model. Exclusion limits are set at the 95\% confidence level in simplified models of general gauge mediated supersymmetry, where Higgsino masses are excluded up to 295 GeV. In R-parity-violating simplified models with decays of the lightest supersymmetric particle to charged leptons, lower limits of 1.46, 1.06, and 2.25 TeV are placed on wino, slepton and gluino masses, respectively.},
  language  = {en}
}
@article{OPUS4-22562,
  title     = {Measurement of long-range multiparticle azimuthal correlations with the subevent cumulant method in \({pp}\) and \(p\)+Pb collisions with the ATLAS detector at the CERN Large Hadron Collider},
  series = {Physical Review C},
  volume    = {97},
  journal   = {Physical Review C},
  number    = {2},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevC.97.024904},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225623},
  pages     = {024904, 1-25},
  year      = {2018},
  abstract  = {A detailed study of multiparticle azimuthal correlations is presented using pp data at root s = 5.02 and 13 TeV, and p+Pb data at root s(NN) = 5.02 TeV, recorded with the ATLAS detector at the CERN Large Hadron Collider. The azimuthal correlations are probed using four-particle cumulants c(n){4} and flow coefficients v(n){4} = (-c(n){4})(1/4) for n = 2 and 3, with the goal of extracting long-range multiparticle azimuthal correlation signals and suppressing the short-range correlations. The values of c(n){4} are obtained as a function of the average number of charged particles per event, < N-ch >, using the recently proposed two-subevent and three-subevent cumulant methods, and compared with results obtained with the standard cumulant method. The standard method is found to be strongly biased by short-range correlations, which originate mostly from jetswith a positive contribution to c(n){4}. The threesubevent method, on the other hand, is found to be least sensitive to short-range correlations. The three-subevent method gives a negative c(2){4}, and therefore a well-defined v(2){4}, nearly independent of < N-ch >, which implies that the long-range multiparticle azimuthal correlations persist to events with low multiplicity. Furthermore, v(2){4} is found to be smaller than the v(2){2} measured using the two-particle correlation method, as expected for long-range collective behavior. Finally, the measured values of v(2){4} and v(2){2} are used to estimate the number of sources relevant for the initial eccentricity in the collision geometry. The results based on the subevent cumulant technique provide direct evidence, in small collision systems, for a long-range collectivity involving many particles distributed across a broad rapidity interval.},
  language  = {en}
}
@article{OPUS4-22087,
  title     = {Measurement of differential cross sections and W\(^+\)/W\(^-\) cross-section ratios for W boson production in association with jets at root s=8 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {77},
  journal   = {Journal of High Energy Physics},
  number    = {5},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP05(2018)077},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220872},
  pages     = {1-61},
  year      = {2018},
  abstract  = {This paper presents a measurement of the W boson production cross section and the W+/W- cross-section ratio, both in association with jets, in proton-proton collisions at root s = 8 TeV with the ATLAS experiment at the Large Hadron Collider. The measurement is performed in final states containing one electron and missing transverse momentum using data corresponding to an integrated luminosity of 20.2 fb(-1). Differential cross sections for events with at least one or two jets are presented for a range of observables, including jet transverse momenta and rapidities, the scalar sum of transverse momenta of the visible particles and the missing transverse momentum in the event, and the transverse momentum of the W boson. For a subset of the observables, the differential cross sections of positively and negatively charged W bosons are measured separately. In the cross-section ratio of W+/W- the dominant systematic uncertainties cancel out, improving the measurement precision by up to a factor of nine. The observables and ratios selected for this paper provide valuable input for the up quark, down quark, and gluon parton distribution functions of the proton.},
  language  = {en}
}
@article{OPUS4-22083,
  title     = {Search for squarks and gluinos in final states with jets and missing transverse momentum using 36 fb\(^{-1}\) of root s=13 TeV \({pp}\) collision data with the ATLAS detector},
  series = {Physical Review D},
  volume    = {97},
  journal   = {Physical Review D},
  number    = {11},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.97.112001},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220835},
  pages     = {1-47},
  year      = {2018},
  abstract  = {A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing hadronic jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded in 2015 and 2016 by the ATLAS experiment in root s = 13 TeV proton-proton collisions at the Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb(-1). The results are interpreted in the context of various models where squarks and gluinos are pair produced and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95\% confidence level on the mass of the gluino is set at 2.03 TeV for a simplified model incorporating only a gluino and the lightest neutralino, assuming the lightest neutralino is massless. For a simplified model involving the strong production of mass-degenerate first-and second-generation squarks, squark masses below 1.55 TeVare excluded if the lightest neutralino is massless. These limits substantially extend the region of supersymmetric parameter space previously excluded by searches with the ATLAS detector.},
  language  = {en}
}
@article{OPUS4-22584,
  title     = {\({ZZ}\) -> l(+)l(-)l '(+)l '(-) cross-section measurements and search for anomalous triple gauge couplings in 13 TeV \({pp}\) collisions with the ATLAS detector},
  series = {Physical Review D},
  volume    = {97},
  journal   = {Physical Review D},
  number    = {3},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.97.032005},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225844},
  pages     = {1-39},
  year      = {2018},
  abstract  = {Measurements of ZZ production in the l(+)l(-)l'(+)l'(-) channel in proton-proton collisions at 13 TeV center-of-mass energy at the Large Hadron Collider are presented. The data correspond to 36.1 fb(-1) of collisions collected by the ATLAS experiment in 2015 and 2016. Here l and l ' stand for electrons or muons. Integrated and differential ZZ -> l(+)l(-)l'(+)l'(-) cross sections with Z -> l(+)l(-) candidate masses in the range of 66 GeV to 116 GeV are measured in a fiducial phase space corresponding to the detector acceptance and corrected for detector effects. The differential cross sections are presented in bins of twenty observables, including several that describe the jet activity. The integrated cross section is also extrapolated to a total phase space and to all standard model decays of Z bosons with mass between 66 GeV and 116 GeV, resulting in a value of 17.3 +/- 0.9 [+/- 0.6(start) +/- 0.5 (syst) +/- 0.6 (lumi)] pb. The measurements are found to be in good agreement with the standard model. A search for neutral triple gauge couplings is performed using the transverse momentum distribution of the leading Z boson candidate. No evidence for such couplings is found and exclusion limits are set on their parameters.},
  language  = {en}
}
@article{OPUS4-22586,
  title     = {Search for \(B\) - \(L\) \(R\)-parity-violating top squarks in root s=13 TeV \({pp}\) collisions with the ATLAS experiment},
  series = {Physical Review D},
  volume    = {97},
  journal   = {Physical Review D},
  number    = {3},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.97.032003},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225863},
  pages     = {1-42},
  year      = {2018},
  abstract  = {A search is presented for the direct pair production of the stop, the supersymmetric partner of the top quark, that decays through an R-parity-violating coupling to a final state with two leptons and two jets, at least one of which is identified as a b-jet. The data set corresponds to an integrated luminosity of 36.1 fb(-1) of proton-proton collisions at a center-of-mass energy of root s = 13 TeV, collected in 2015 and 2016 by the ATLAS detector at the LHC. No significant excess is observed over the Standard Model background, and exclusion limits are set on stop pair production at a 95\% confidence level. Lower limits on the stop mass are set between 600 GeV and 1.5 TeV for branching ratios above 10\% for decays to an electron or muon and a b-quark.},
  language  = {en}
}
@article{OPUS4-22541,
  title     = {Measurement of the cross section for isolated-photon plus jet production in \({pp}\) collisions at root s=13 TeV using the ATLAS detector},
  series = {Physics Letters B},
  volume    = {780},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.03.035},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225412},
  pages     = {578-602},
  year      = {2018},
  abstract  = {The dynamics of isolated-photon production in association with a jet in proton-proton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fb(-1). Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti-k(t) algorithm with radius parameter R = 0.4 and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photon-jet invariant mass and the scattering angle in the photon-jet centre-of-mass system. Tree-level plus parton-shower predictions from SHERPA and PYTHIA as well as next-to-leading-order QCD predictions from JETPHOX and SHERPA are compared to the measurements. (C) 2018 The Author. Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22582,
  title     = {Measurement of the exclusive gamma gamma -> mu\(^+\)mu\(^-\) process in proton-proton collisions at root s=13 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {777},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2017.12.043},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225825},
  pages     = {303-323},
  year      = {2018},
  abstract  = {The production of exclusive gamma gamma -> mu(+)mu(-) events in proton-proton collisions at a centre-of-mass energy of 13 TeV is measured with the ATLAS detector at the LHC, using data corresponding to an integrated luminosity of 3.2 fb(-1). The measurement is performed for a dimuon invariant mass of 12 GeV < m(mu+mu-) < 70 GeV. The integrated cross-section is determined within a fiducial acceptance region of the ATLAS detector and differential cross-sections are measured as a function of the dimuon invariant mass. The results are compared to theoretical predictions both with and without corrections for absorptive effects. (c) 2017 The Author(s). Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22067,
  title     = {Angular analysis of B-d(0) -> K* µ\(^+\)μ\(^-\) decays in \({pp}\) collisions at root s=8 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {47},
  journal   = {Journal of High Energy Physics},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP10(2018)047},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220670},
  pages     = {1-47},
  year      = {2018},
  abstract  = {An angular analysis of the decay B-d(0) -> K*mu(+)mu(-) is presented, based on proton-proton collision data recorded by the ATLAS experiment at the LHC. The study is using 20.3 fb(-1) of integrated luminosity collected during 2012 at centre-of-mass energy of root s = 8TeV. Measurements of the K* longitudinal polarisation fraction and a set of angular parameters obtained for this decay are presented. The results are compatible with the Standard Model predictions.},
  language  = {en}
}
@article{OPUS4-22071,
  title     = {Search for exclusive Higgs and Z boson decays to phi gamma and rho gamma with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {127},
  journal   = {Journal of High Energy Physics},
  number    = {7},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP07(2018)127},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220717},
  pages     = {1-36},
  year      = {2018},
  abstract  = {A search for the exclusive decays of the Higgs and Z bosons to a phi or rho meson and a photon is performed with a pp collision data sample corresponding to an integrated luminosity of up to 35.6 fb(-1) collected at root s = 13 TeV with the ATLAS detector at the CERN Large Hadron Collider. These decays have been suggested as a probe of the Higgs boson couplings to light quarks. No significant excess of events is observed above the background, as expected from the Standard Model. Upper limits at 95\% confidence level were obtained on the branching fractions of the Higgs boson decays to phi gamma and rho gamma of 4.8 x 10(-4) and 8.8 x 10(-4), respectively. The corresponding 95\% confidence level upper limits for the Z boson decays are 0.9 x 10(-6) and 25 x 10(-6) for phi gamma and rho gamma, respectively.},
  language  = {en}
}
@article{OPUS4-22545,
  title     = {Search for long-lived, massive particles in events with displaced vertices and missing transverse momentum in root S=13 TeV \({pp}\) collisions with the ATLAS detector},
  series = {Physical Review D},
  volume    = {97},
  journal   = {Physical Review D},
  number    = {5},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.97.052012},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225450},
  pages     = {1-29},
  year      = {2018},
  abstract  = {A search for long-lived, massive particles predicted by many theories beyond the Standard Model is presented. The search targets final states with large missing transverse momentum and at least one highmass displaced vertex with five or more tracks, and uses 32.8 fb(-1) of root s = 13 TeV pp collision data collected by the ATLAS detector at the LHC. The observed yield is consistent with the expected background. The results are used to extract 95\% C.L. exclusion limits on the production of long-lived gluinos with masses up to 2.37 TeV and lifetimes of O(10(-2)) - O(10) ns in a simplified model inspired by split supersymmetry.},
  language  = {en}
}
@article{OPUS4-22084,
  title     = {Search for long-lived charginos based on a disappearing-track signature in pp collisions at root s=13 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {22},
  journal   = {Journal of High Energy Physics},
  number    = {6},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP06(2018)022},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220847},
  pages     = {1-46},
  year      = {2018},
  abstract  = {This paper presents a search for direct electroweak gaugino or gluino pair production with a chargino nearly mass-degenerate with a stable neutralino. It is based on an integrated luminosity of 36.1 fb(-1) of pp collisions at root s = 13 TeV collected by the ATLAS experiment at the LHC. The final state of interest is a disappearing track accompanied by at least one jet with high transverse momentum from initial-state radiation or by four jets from the gluino decay chain. The use of short track segments reconstructed from the innermost tracking layers significantly improves the sensitivity to short chargino lifetimes. The results are found to be consistent with Standard Model predictions. Exclusion limits are set at 95\% confidence level on the mass of charginos and gluinos for different chargino lifetimes. For a pure wino with a lifetime of about 0.2 ns, chargino masses up to 460 GeV are excluded. For the strong production channel, gluino masses up to 1.65 TeV are excluded assuming a chargino mass of 460 GeV and lifetime of 0.2 ns.},
  language  = {en}
}
@article{OPUS4-22073,
  title     = {Search for top-squark pair production in final states with one lepton, jets, and missing transverse momentum using 36 fb\(^{-1}\) of root s=13 TeV \({pp}\) collision data with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {108},
  journal   = {Journal of High Energy Physics},
  number    = {6},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP06(2018)108},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220733},
  pages     = {1-95},
  year      = {2018},
  abstract  = {The results of a search for the direct pair production of top squarks, the supersymmetric partner of the top quark, in final states with one isolated electron or muon, several energetic jets, and missing transverse momentum are reported. The analysis also targets spin-0 mediator models, where the mediator decays into a pair of dark-matter particles and is produced in association with a pair of top quarks. The search uses data from proton-proton collisions delivered by the Large Hadron Collider in 2015 and 2016 at a centre-of-mass energy of root s = 13TeV and recorded by the ATLAS detector, corresponding to an integrated luminosity of 36 fb(-1). A wide range of signal scenarios with different mass-splittings between the top squark, the lightest neutralino and possible intermediate supersymmetric particles are considered, including cases where the W bosons or the top quarks produced in the decay chain are off-shell. No significant excess over the Standard Model prediction is observed. The null results are used to set exclusion limits at 95\% confidence level in several supersymmetry benchmark models. For pair-produced top-squarks decaying into top quarks, top-squark masses up to 940 GeV are excluded. Stringent exclusion limits are also derived for all other considered top-squark decay scenarios. For the spin-0 mediator models, upper limits are set on the visible cross-section.},
  language  = {en}
}
@article{OPUS4-22074,
  title     = {Search for supersymmetry in final states with missing transverse momentum and multiple b-jets in proton-proton collisions at root s=13 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {107},
  journal   = {Journal of High Energy Physics},
  number    = {6},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP06(2018)107},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220748},
  pages     = {1-55},
  year      = {2018},
  abstract  = {A search for supersymmetry involving the pair production of gluinos decaying via third-generation squarks into the lightest neutralino ((chi) over tilde (0)(1)) is reported. It uses LHC proton-proton collision data at a centre-of-mass energy root s = 13TeV with an integrated luminosity of 36.1 fb(-1) collected with the ATLAS detector in 2015 and 2016. The search is performed in events containing large missing transverse momentum and several energetic jets, at least three of which must be identified as originating from b-quarks. To increase the sensitivity, the sample is divided into subsamples based on the presence or absence of electrons or muons. No excess is found above the predicted background. For (chi) over tilde (0)(1) masses below approximately 300 GeV, gluino masses of less than 1.97 (1.92) TeV are excluded at 95\% confidence level in simplified models involving the pair production of gluinos that decay via top (bottom) squarks. An interpretation of the limits in terms of the branching ratios of the gluinos into third-generation squarks is also provided. These results improve upon the exclusion limits obtained with the 3.2 fb(-1) of data collected in 2015.},
  language  = {en}
}
@article{OPUS4-22085,
  title     = {Measurement of inclusive jet and dijet cross-sections in proton-proton collisions at root s=13 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {195},
  journal   = {Journal of High Energy Physics},
  number    = {5},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP05(2018)195},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220853},
  pages     = {1-48},
  year      = {2018},
  abstract  = {Inclusive jet and dijet cross-sections are measured in proton-proton collisions at a centre-of-mass energy of 13 TeV. The measurement uses a dataset with an integrated luminosity of 3.2 fb(-1) recorded in 2015 with the ATLAS detector at the Large Hadron Collider. Jets are identified using the anti-lit algorithm with a radius parameter value of R = 0.4. The inclusive jet cross-sections are measured double-differentially as a function of the jet transverse momentum, covering the range from 100 GeV to 3.5 TeV, and the absolute jet rapidity up to vertical bar y vertical bar = 3. The double-differential dijet production cross-sections are presented as a function of the dijet mass, covering the range from 300 GeV to 9 TeV, and the half absolute rapidity separation between the two leading jets within vertical bar y vertical bar < 3, y*, up to y* = 3. Next-to-leading-order, and next-to-next-to-leading-order for the inclusive jet measurement, perturbative QCD calculations corrected for non-perturbative and electroweak effects are compared to the measured cross-sections.},
  language  = {en}
}
@article{OPUS4-22609,
  title     = {Search for a heavy Higgs boson decaying into a \(Z\) boson and another heavy Higgs boson in the \({llbb}\) final state in \({pp}\) collisions at root \(s\)=13 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {783},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.07.006},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226098},
  pages     = {392-414},
  year      = {2018},
  abstract  = {A search for a heavy neutral Higgs boson, A, decaying into a Z boson and another heavy Higgs boson, H, is performed using a data sample corresponding to an integrated luminosity of 36.1 fb(-1) from proton-proton collisions at root s = 13 TeV recorded in 2015 and 2016 by the ATLAS detector at the Large Hadron Collider. The search considers the Z boson decaying to electrons or muons and the H boson into a pair of b-quarks. No evidence for the production of an A boson is found. Considering each production process separately, the 95\% confidence-level upper limits on the pp -> A -> ZH production cross-section times the branching ratio H -> bb are in the range of 14-830 fb for the gluon-gluon fusion process and 26-570 fb for the b-associated process for the mass ranges 130-700 GeV of the H boson and 230-800 GeV of the A boson. The results are interpreted in the context of two-Higgs-doublet models. (C) 2018 Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3).},
  language  = {en}
}
@article{OPUS4-22606,
  title     = {Measurement of the Higgs boson mass in the \(H\) -> \({ZZ}\)* -> 4l and \(H\) -> \({γγ}\) channels with root \(s\)=13 TeV \({pp}\) collisions using the ATLAS detector},
  series = {Physics Letters B},
  volume    = {784},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.07.050},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226065},
  pages     = {345-366},
  year      = {2018},
  abstract  = {The mass of the Higgs boson is measured in the H -> ZZ* -> 4l and in the H -> gamma gamma decay channels with 36.1 fb(-1) of proton-proton collision data from the Large Hadron Collider at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector in 2015 and 2016. The measured value in the H -> ZZ* -> 4l channel is m(H)(ZZ*) = 124.79 +/- 0.37 GeV, while the measured value in the H -> gamma gamma channel is m(H)(gamma gamma) = 124.93 +/- 0.40 GeV. Combining these results with the ATLAS measurement based on 7 and 8 TeV proton-proton collision data yields a Higgs boson mass of m(H) = 124.97 +/- 0.24 GeV. (c) 2018 The Author. Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22614,
  title     = {Search for Higgs boson decays into pairs of light (pseudo)scalar particles in the \({γγ jj}\) final state in \({pp}\) collisions at root \(s\)=13 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {782},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.06.011},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226147},
  pages     = {750-767},
  year      = {2018},
  abstract  = {This Letter presents a search for exotic decays of the Higgs boson to a pair of new (pseudo) scalar particles, H -> aa, where the a particle has a mass in the range 20-60 GeV, and where one of the a bosons decays into a pair of photons and the other to a pair of gluons. The search is performed in event samples enhanced in vector-boson fusion Higgs boson production by requiring two jets with large invariant mass in addition to the Higgs boson candidate decay products. The analysis is based on the full dataset of pp collisions at root s = 13 TeV recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 36.7 fb(-1). The data are in agreement with the Standard Model predictions and an upper limit at the 95\% confidence level is placed on the production cross section times the branching ratio for the decay H -> aa -> gamma gamma gg. This limit ranges from 3.1 pb to 9.0 pb depending on the mass of the a boson. (C) 2018 The Author. Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22654,
  title     = {Search for the standard model Higgs boson produced in association with top quarks and decaying into a b(b)overbar pair in \(pp\) collisions at root \(s\)=13 TeV with the ATLAS detector},
  series = {Physical Review D},
  volume    = {97},
  journal   = {Physical Review D},
  number    = {7},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.97.072016},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226545},
  pages     = {1-44},
  year      = {2018},
  abstract  = {A search for the standard model Higgs boson produced in association with a top-quark pair, t(t)overbarH, is presented. The analysis uses 36.1 fb(-1) of pp collision data at root s = 13 TeV collected with the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The search targets the H -> b(b)overbar decay mode. The selected events contain either one or two electrons or muons from the top-quark decays, and are then categorized according to the number of jets and how likely these are to contain b-hadrons. Multivariate techniques are used to discriminate between signal and background events, the latter being dominated by ft + jets production. For a Higgs boson mass of 125 GeV, the ratio of the measured t(t)overbarH signal cross-section to the standard model expectation is found to be mu = 0.84(-0.61)(+0.64). A value of mu greater than 2.0 is excluded at 95\% confidence level (C.L.) while the expected upper limit is mu < 1.2 in the absence of a t(t)overbarH signal.},
  language  = {en}
}
@article{OPUS4-22656,
  title     = {Evidence for the associated production of the Higgs boson and a top quark pair with the ATLAS detector},
  series = {Physical Review D},
  volume    = {97},
  journal   = {Physical Review D},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.97.072003},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226569},
  pages     = {1-44},
  year      = {2018},
  abstract  = {A search for the associated production of the Higgs boson with a top quark pair (tt (b) over barH) is reported. The search is performed in multilepton final states using a data set corresponding to an integrated luminosity of 36.1 fb(-1) of proton-proton collision data recorded by the ATLAS experiment at a center-of-mass energy root s = 13 TeV at the Large Hadron Collider. Higgs boson decays to WW*, tau tau, and ZZ* are targeted. Seven final states, categorized by the number and flavor of charged-lepton candidates, are examined for the presence of the Standard Model Higgs boson with a mass of 125 GeVand a pair of top quarks. An excess of events over the expected background from Standard Model processes is found with an observed significance of 4.1 standard deviations, compared to an expectation of 2.8 standard deviations. The best fit for the (tt (b) over barH) production cross section is sot (tt (b) over barH) = 790(-210)(+230) fb, in agreement with the Standard Model prediction of 507(-50)(+35) fb. The combination of this result with other tt (b) over barH searches from the ATLAS experiment using the Higgs boson decay modes to b (b) over bar, gamma gamma and ZZ* -> 4l, has an observed significance of 4.2 standard deviations, compared to an expectation of 3.8 standard deviations. This provides evidence for the tt (b) over barH production mode.},
  language  = {en}
}
@article{OPUS4-22651,
  title     = {Search for photonic signatures of gauge-mediated supersymmetry in 13 TeV \(pp\) collisions with the ATLAS detector},
  series = {Physical Review D},
  volume    = {97},
  journal   = {Physical Review D},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.97.092006},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226510},
  pages     = {1-32},
  year      = {2018},
  abstract  = {A search is presented for photonic signatures, motivated by generalized models of gauge-mediated supersymmetry breaking. This search makes use of proton-proton collision data at root s = 13 TeV corresponding to an integrated luminosity of 36.1 fb(-1) recorded by the ATLAS detector at the LHC, and it explores models dominated by both strong and electroweak production of supersymmetric partner states. Experimental signatures incorporating an isolated photon and significant missing transverse momentum are explored. These signatures include events with an additional photon or additional jet activity not associated with any specific underlying quark flavor. No significant excess of events is observed above the Standard Model prediction, and 95\% confidence-level upper limits of between 0.083 and 0.32 fb are set on the visible cross section of contributions from physics beyond the Standard Model. These results are interpreted in terms of lower limits on the masses of gluinos, squarks, and gauginos in the context of generalized models of gauge-mediated supersymmetry, which reach as high as 2.3 TeV for strongly produced and 1.3 TeV for weakly produced supersymmetric partner pairs.},
  language  = {en}
}
@article{OPUS4-22596,
  title     = {Comparison between simulated and observed LHC beam backgrounds in the ATLAS experiment at \(E\)\(_{beam}\)=4 TeV},
  series = {Journal of Instrumentation},
  volume    = {13},
  journal   = {Journal of Instrumentation},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1088/1748-0221/13/12/P12006},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225966},
  pages     = {1-40},
  year      = {2018},
  abstract  = {Results of dedicated Monte Carlo simulations of beam-induced background (BIB) in the ATLAS experiment at the Large Hadron Collider (LHC) are presented and compared with data recorded in 2012. During normal physics operation this background arises mainly from scattering of the 4 TeV protons on residual gas in the beam pipe. Methods of reconstructing the BIB signals in the ATLAS detector, developed and implemented in the simulation chain based on the FLUKA Monte Carlo simulation package, are described. The interaction rates are determined from the residual gas pressure distribution in the LHC ring in order to set an absolute scale on the predicted rates of BIB so that they can be compared quantitatively with data. Through these comparisons the origins of the BIB leading to different observables in the ATLAS detectors are analysed. The level of agreement between simulation results and BIB measurements by ATLAS in 2012 demonstrates that a good understanding of the origin of BIB has been reached.},
  language  = {en}
}
@article{OPUS4-22595,
  title     = {Searches for heavy \({ZZ}\) and \({ZW}\) resonances in the \({llqq}\) and \({vvqq}\) final states in \({pp}\) collisions at root s=13 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {9},
  journal   = {Journal of High Energy Physics},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1007/JHEP03(2018)009},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225951},
  pages     = {1-52},
  year      = {2018},
  abstract  = {This paper reports searches for heavy resonances decaying into ZZ or ZW using data from proton-proton collisions at a centre-of-mass energy of root s - 13 TeV. The data, corresponding to an integrated luminosity of 36.1 fb(-1), were recorded with the ATLAS detector in 2015 and 2016 at the Large Hadron Collider. The searches are performed in final states in which one Z boson decays into either a pair of light charged leptons (electrons and muons) or a pair of neutrinos, and the associated W boson or the other Z boson decays hadronically. No evidence of the production of heavy resonances is observed. Upper bounds on the production cross sections of heavy resonances times their decay branching ratios to ZZ or ZW are derived in the mass range 300-5000 GeV within the context of Standard Model extensions with additional Higgs bosons, a heavy vector triplet or warped extra dimensions. Production through gluon-gluon fusion, Drell-Yan or vector-boson fusion are considered, depending on the assumed model.},
  language  = {en}
}
@article{OPUS4-22598,
  title     = {Search for W ' -> \({tb}\) decays in the hadronic final state using \({pp}\) collisions at root s=13 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {781},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.03.036},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225987},
  pages     = {327-348},
  year      = {2018},
  abstract  = {A search for W'-boson production in the W' -> t (b) over bar -> q (q) over bar 'b (b) over bar decay channel is presented using 36.1 fb(-1) of 13 TeV proton-proton collision data collected by the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The search is interpreted in terms of both a left-handed and a right-handed chiral W' boson within the mass range 1-5 TeV. Identification of the hadronically decaying top quark is performed using jet substructure tagging techniques based on a shower deconstruction algorithm. No significant deviation from the Standard Model prediction is observed and the results are expressed as upper limits on the W' -> t (b) over bar production cross-section times branching ratio as a function of the W'-boson mass. These limits exclude W' bosons with right-handed couplings with masses below 3.0 TeV and W' bosons with left-handed couplings with masses below 2.9 TeV, at the 95\% confidence level. (C) 2018 The Author. Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22604,
  title     = {Search for R-parity-violating supersymmetric particles in multi-jet final states produced in \({p-p}\) collisions at root \(s\)=13 TeV using the ATLAS detector at the LHC},
  series = {Physics Letters B},
  volume    = {785},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.08.021},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226047},
  pages     = {136-158},
  year      = {2018},
  abstract  = {Results of a search for gluino pair production with subsequent R-parity-violating decays to quarks are presented. This search uses 36.1 fb(-1) of data collected by the ATLAS detector in proton-proton collisions with a centre-of-mass energy of root s = 13 TeV at the LHC. The analysis is performed using requirements on the number of jets and the number of jets tagged as containing a b-hadron as well as a topological observable formed by the scalar sum of masses of large-radius jets in the event. No significant excess above the expected Standard Model background is observed. Limits are set on the production of gluinos in models with the R-parity-violating decays of either the gluino itself (direct decay) or the neutralino produced in the R-parity-conserving gluino decay (cascade decay). In the gluino cascade decay model, gluino masses below 1850 GeV are excluded for 1000 GeV neutralino mass. For the gluino direct decay model, the 95\% confidence level upper limit on the cross section times branching ratio varies between 0.80 fb at m((g) over tilde) = 900 GeV and 0.011 fb at m((g) over tilde) = 1800 GeV. (c) 2018 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license.},
  language  = {en}
}
@article{OPUS4-22559,
  title     = {Search for doubly charged Higgs boson production in multi-lepton final states with the ATLAS detector using proton-proton collisions at root s=13TeV},
  series = {The European Physical Journal C},
  volume    = {78},
  journal   = {The European Physical Journal C},
  number    = {199},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-018-5661-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225591},
  pages     = {1-34},
  year      = {2018},
  abstract  = {A search for doubly charged Higgs bosons with pairs of prompt, isolated, highly energetic leptons with the same electric charge is presented. The search uses a proton-proton collision data sample at a centre-of-mass energy of 13 TeV corresponding to 36.1 fb(-1) of integrated luminosity recorded in 2015 and 2016 by the ATLAS detector at the LHC. This analysis focuses on the decays H-+/-+/- -> e(+/-)e(+/-), H-+/-+/- -> e(+/-)mu(+/-) and H-+/-+/- -> mu(+/-)mu(+/-), fitting the dilepton mass spectra in several exclusive signal regions. No significant evidence of a signal is observed and corresponding limits on the production cross-section and consequently a lower limit on m(H-+/-+/-) are derived at 95\% confidence level. With l(+/-)l(+/-) = e(+/-)e(+/-)/mu(+/-)mu(+/-)/e(+/-)mu(+/-), the observed lower limit on the mass of a doubly charged Higgs boson only coupling to left-handed leptons varies from 770 to 870GeV (850GeV expected) for B(H-+/-+/- -> l(+/-)l(+/-)) = 100\% and both the expected and observed mass limits are above 450GeV for B(H-+/-+/- -> l(+/-)l(+/-)) = 10\% and any combination of partial branching ratios.},
  language  = {en}
}
@article{OPUS4-22560,
  title     = {Search for the direct production of charginos and neutralinos in final states with tau leptons in root s=13 TeV pp collisions with the ATLAS detector},
  series = {The European Physical Journal C},
  volume    = {78},
  journal   = {The European Physical Journal C},
  number    = {154},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-018-5583-9},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225602},
  pages     = {1-33},
  year      = {2018},
  abstract  = {A search for the direct production of charginos and neutralinos in final states with at least two hadronically decaying tau leptons is presented. The analysis uses a dataset of pp collisions corresponding to an integrated luminosity of 36.1 fb, recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV. No significant deviation from the expected Standard Model background is observed. Limits are derived in scenarios of pair production and of and production in simplified models where the neutralinos and charginos decay solely via intermediate left-handed staus and tau sneutrinos, and the mass of the state is set to be halfway between the masses of the and the (chi) over tilde (0.)(1) . Chargino masses up to 630 GeV are excluded at 95\% confidence level in the scenario of direct production of for a massless (chi) over tilde (0.)(1). Common and masses up to 760 GeV are excluded in the case of production of and assuming a massless . Exclusion limits for additional benchmark scenarios with large and small mass-splitting between the and the are also studied by varying the mass between the masses of the and the (chi) over tilde (0.)(1)},
  language  = {en}
}
@article{OPUS4-22561,
  title     = {Measurement of longitudinal flow decorrelations in Pb plus Pb collisions at root s(NN)=2.76 and 5.02 TeV with the ATLAS detector},
  series = {The European Physical Journal C},
  volume    = {78},
  journal   = {The European Physical Journal C},
  number    = {142},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-018-5605-7},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225610},
  pages     = {1-37},
  year      = {2018},
  abstract  = {Measurements of longitudinal flow correlations are presented for charged particles in the pseudorapidity range vertical bar eta vertical bar < 2.4 using 7 mu b(-1) and 470 mu b(-1) of Pb+Pb collisions at root s(NN) = 2.76 and 5.02 TeV, respectively, recorded by the ATLAS detector at the LHC. It is found that the correlation between the harmonic flow coefficients v(n) measured in two separated eta intervals does not factorise into the product of single-particle coefficients, and this breaking of factorisation, or flow decorrelation, increases linearly with the eta separation between the intervals. The flow decorrelation is stronger at 2.76 TeVthan at 5.02 TeV. Higher-order moments of the correlations are also measured, and the corresponding linear coefficients for the kth-moment of the v(n) are found to be proportional to k for v(3), but not for v(2). The decorrelation effect is separated into contributions from the magnitude of v(n) and the event-plane orientation, each as a function of eta. These two contributions are found to be comparable. The longitudinal flow correlations are also measured between v(n) of different order in n. The decorrelations of v(2) and v(3) are found to be independent of each other, while the decorrelations of v(4) and v(5) are found to be driven by the nonlinear contribution from v(2)(2) and v(2)v(3), respectively.},
  language  = {en}
}
@article{OPUS4-22588,
  title     = {Search for new phenomena in high-mass final states with a photon and a jet from \({pp}\) collisions at root s=13 TeV with the ATLAS detector},
  series = {The European Physical Journal C},
  volume    = {78},
  journal   = {The European Physical Journal C},
  number    = {102},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-018-5553-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225887},
  pages     = {1-25},
  year      = {2018},
  abstract  = {A search is performed for new phenomena in events having a photon with high transverse momentum and a jet collected in 36.7 fb(-1) of proton-proton collisions at a centre-of-mass energy of root s = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider. The invariant mass distribution of the leading photon and jet is examined to look for the resonant production of new particles or the presence of new high-mass states beyond the Standard Model. No significant deviation from the background-only hypothesis is observed and cross-section limits for generic Gaussian-shaped resonances are extracted. Excited quarks hypothesized in quark compositeness models and high-mass states predicted in quantum black hole models with extra dimensions are also examined in the analysis. The observed data exclude, at 95\% confidence level, the mass range below 5.3 TeV for excited quarks and 7.1 TeV (4.4 TeV) for quantum black holes in the Arkani-Hamed-Dimopoulos-Dvali (Randall-Sundrum) model with six (one) extra dimensions.},
  language  = {en}
}