@article{OPUS4-12763, title = {Search for lepton flavour violation in the eμ continuum with the ATLAS detector in √s=7 TeV pp collisions at the LHC}, series = {The European Physical Journal C}, volume = {72}, journal = {The European Physical Journal C}, number = {2040}, organization = {ATLAS Collaboration}, doi = {10.1140/epjc/s10052-012-2040-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127632}, year = {2012}, abstract = {This paper presents a search for the t-channel exchange of an R-parity violating scalar top quark ( \(\tilde{t}\) ) in the e\(^±\) μ\(^∓\) continuum using 2.1 fb\(^{-1}\) of data collected by the ATLAS detector in √s=7 TeV pp collisions at the Large Hadron Collider. Data are found to be consistent with the expectation from the Standard Model backgrounds. Limits on R-parity-violating couplings at 95 \% C.L. are calculated as a function of the scalar top mass (m\(_\tilde{t}\)). The upper limits on the production cross section for pp→eμX, through the t-channel exchange of a scalar top quark, ranges from 170 fb for m\(_\tilde{t}\)=95 GeV to 30 fb for m\(_\tilde{t}\)=1000 GeV.}, language = {en} } @article{OPUS4-12761, title = {Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at √s=7 TeV with the ATLAS experiment}, series = {The European Physical Journal C}, volume = {72}, journal = {The European Physical Journal C}, number = {2001}, organization = {ATLAS Collaboration}, doi = {10.1140/epjc/s10052-012-2001-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127615}, year = {2012}, abstract = {This paper describes an analysis of the angular distribution of W→eν and W→μν decays, using data from pp collisions at s√=7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb\(^{-1}\). Using the decay lepton transverse momentum and the missing transverse momentum, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f\(_0\), f\(_L\) and f\(_R\) over two ranges of W transverse momentum (p\(^W_T\)):3550 GeV. Good agreement is found with theoretical predictions. For p\(^W_T\)>50 GeV, the values of f\(_0\) and f\(_L\)-f\(_R\), averaged over charge and lepton flavour, are measured to be: f\(_0\)=0.127±0.030±0.108 and f\(_L\)-f\(_R\)=0.252±0.017±0.030, where the first uncertainties are statistical, and the second include all systematic effects.}, language = {en} }