Constraints on the off-shell Higgs boson signal strength in the high-mass ZZ and WW final states with the ATLAS detector
Please always quote using this URN: urn:nbn:de:bvb:20-opus-149615
- Measurements of the ZZ and WW final states in the mass range above the 2m\(_Z\) and 2m\(_W\) thresholds provide a unique opportunity to measure the off-shell coupling strength of the Higgs boson. This paper presents constraints on the off-shell Higgs boson event yields normalised to the Standard Model prediction (signal strength) in the ZZ→4ℓ, ZZ→2ℓ2ν and WW→eνμν final states. The result is based on pp collision data collected by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 20.3 fb\(^{-1}\) at a collision energyMeasurements of the ZZ and WW final states in the mass range above the 2m\(_Z\) and 2m\(_W\) thresholds provide a unique opportunity to measure the off-shell coupling strength of the Higgs boson. This paper presents constraints on the off-shell Higgs boson event yields normalised to the Standard Model prediction (signal strength) in the ZZ→4ℓ, ZZ→2ℓ2ν and WW→eνμν final states. The result is based on pp collision data collected by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 20.3 fb\(^{-1}\) at a collision energy of \(\sqrt {s}\)=8 TeV. Using the CL\(_S\) method, the observed 95 % confidence level (CL) upper limit on the off-shell signal strength is in the range 5.1–8.6, with an expected range of 6.7–11.0. In each case the range is determined by varying the unknown gg→ZZ and gg→WW background K-factor from higher-order quantum chromodynamics corrections between half and twice the value of the known signal K-factor. Assuming the relevant Higgs boson couplings are independent of the energy scale of the Higgs boson production, a combination with the on-shell measurements yields an observed (expected) 95 % CL upper limit on Γ\(_H\)/Γ\(^{SM}_{H}\) in the range 4.5–7.5 (6.5–11.2) using the same variations of the background K-factor. Assuming that the unknown gg→VV background K-factor is equal to the signal K-factor, this translates into an observed (expected) 95 % CL upper limit on the Higgs boson total width of 22.7 (33.0) MeV.…
| URN: | urn:nbn:de:bvb:20-opus-149615 |
|---|---|
| Document Type: | Journal article |
| Faculties: | Fakultät für Physik und Astronomie / Physikalisches Institut |
| Language: | English |
| Parent Title (English): | European Physical Journal C: Particles and Fields |
| Year of Completion: | 2015 |
| Volume: | 75 |
| Issue: | 7 |
| Pagenumber: | 335 |
| Source: | European Physical Journal C: Particles and Fields (2015) 75(7):335. DOI: 10.1140/epjc/s10052-015-3542-2 |
| DOI: | https://doi.org/10.1140/epjc/s10052-015-3542-2 |
| Pubmed Id: | https://pubmed.ncbi.nlm.nih.gov/PMC4509704 |
| Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 53 Physik / 539 Moderne Physik |
| Tag: | Higgs boson; coupling strength |
| Release Date: | 2019/01/28 |
| Creating Corporation: | ATLAS Collaboration |
| Licence (German): |  CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International |