Constraints on the off-shell Higgs boson signal strength in the high-mass ZZ and WW final states with the ATLAS detector

Measurements of the ZZ and WW final states in the mass range above the 2mZ2mZ and 2mW2mW 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 p...

Descripción completa

Detalles Bibliográficos
Autores: Aad, G., Abbott, B., Abdallah, J., Abdinov, O., Aben, R., Alconada Verzini, María Josefina, Alonso, Francisco, Arduh, Francisco Anuar, Dova, Maria Teresa, Monticelli, Fernando Gabriel, Wahlberg, Hernan Pablo, Otero y Garzon, Gustavo Javier, Piegaia, Ricardo Nestor, Reisin, Hernan Diego, Sacerdoti, Sabrina, Zieminska, D., Zimine, N. I., Zimmermann, C., Zimmermann, R., Zimmermann, S., Zinonos, Z., Zinser, M., Ziolkowski, M., Živković, L., Zobernig, G., Zoccoli, A., Nedden, M. zur, Zurzolo, G., Zwalinski, L., The ATLAS Collaboration
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/57501
Acceso en línea:http://hdl.handle.net/11336/57501
Access Level:acceso abierto
Palabra clave:ATLAS
Higgs off-shell
Z W bosons
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:Measurements of the ZZ and WW final states in the mass range above the 2mZ2mZ and 2mW2mW 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→4ℓZZ→4ℓ , ZZ→2ℓ2νZZ→2ℓ2ν and WW→eνμνWW→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 −1−1 at a collision energy of s√=8s=8 TeV. Using the CLsCLs 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→ZZgg→ZZ and gg→WWgg→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 ΓH/ΓSMHΓH/ΓHSM 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→VVgg→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.

Similares en LA Referencia