Abstract: A search for Higgs boson production in association with a W or Z boson, in the H→ W W∗ decay channel, is performed with a data sample collected with the ATLAS detector at the LHC in proton-proton collisions at centre-of-mass energies √s=7$$ sqrts=7 $$ TeV and 8 TeV, corresponding to integrated luminosities of 4.5 fb−1 and 20.3 fb−1, respectively. The WH production mode is studied in two-lepton and three-lepton final states, while two- lepton and four-lepton final states are used to search for the ZH production mode. The observed significance, for the combined W H and ZH production, is 2.5 standard deviations while a significance of 0.9 standard deviations is expected in the Standard Model Higgs boson hypothesis. The ratio of the combined W H and ZH signal yield to the Standard Model expectation, μV H , is found to be μV H = 3.0− 1.1 + 1.3(stat.)− 0.7 + 1.0(sys.) for the Higgs boson mass of 125.36 GeV. The W H and ZH production modes are also combined with the gluon fusion and vector boson fusion production modes studied in the H → W W∗ → ℓνℓν decay channel, resulting in an overall observed significance of 6.5 standard deviations and μggF + VBF + VH = 1. 16− 0.15 + 0.16(stat.)− 0.15 + 0.18(sys.). The results are interpreted in terms of scaling factors of the Higgs boson couplings to vector bosons (κV ) and fermions (κF ); the combined results are: |κV| = 1.06− 0.10 + 0.10, |κF| = 0. 85− 0.20 + 0.26.[Figure not available: see fulltext.] © 2015, The Author(s).

Study of (W/Z)H production and Higgs boson couplings using H→ W W∗ decays with the ATLAS detector / Aad, G; Aloisio, Alberto; Alviggi, Mariagrazia; Canale, Vincenzo; DELLA VOLPE, Domenico; Merola, Leonardo; Conventi, Francesco; DELLA PIETRA, Massimo; Giordano, Raffaele; Perrella, Sabrina; Rossi, Elvira; Cirotto, Francesco; SANCHEZ PINEDA, ARTURO RODOLFO; Carlino, Gianpaolo; DE ASMUNDIS, Riccardo; DI DONATO, Camilla; Doria, Alessandra; Iengo, Paolo; Izzo, Vincenzo; Sekhniaidze, Givi; Et, A. l.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - 2015:8(2015). [10.1007/JHEP08(2015)137]

Study of (W/Z)H production and Higgs boson couplings using H→ W W∗ decays with the ATLAS detector

ALOISIO, ALBERTO;ALVIGGI, MARIAGRAZIA;CANALE, VINCENZO;DELLA VOLPE, DOMENICO;MEROLA, LEONARDO;CONVENTI, FRANCESCO;DELLA PIETRA, MASSIMO;GIORDANO, RAFFAELE;PERRELLA, SABRINA;ROSSI, ELVIRA;CIROTTO, FRANCESCO;SANCHEZ PINEDA, ARTURO RODOLFO;CARLINO, GIANPAOLO;DE ASMUNDIS, Riccardo;DI DONATO, CAMILLA;IENGO, PAOLO;IZZO, VINCENZO;
2015

Abstract

Abstract: A search for Higgs boson production in association with a W or Z boson, in the H→ W W∗ decay channel, is performed with a data sample collected with the ATLAS detector at the LHC in proton-proton collisions at centre-of-mass energies √s=7$$ sqrts=7 $$ TeV and 8 TeV, corresponding to integrated luminosities of 4.5 fb−1 and 20.3 fb−1, respectively. The WH production mode is studied in two-lepton and three-lepton final states, while two- lepton and four-lepton final states are used to search for the ZH production mode. The observed significance, for the combined W H and ZH production, is 2.5 standard deviations while a significance of 0.9 standard deviations is expected in the Standard Model Higgs boson hypothesis. The ratio of the combined W H and ZH signal yield to the Standard Model expectation, μV H , is found to be μV H = 3.0− 1.1 + 1.3(stat.)− 0.7 + 1.0(sys.) for the Higgs boson mass of 125.36 GeV. The W H and ZH production modes are also combined with the gluon fusion and vector boson fusion production modes studied in the H → W W∗ → ℓνℓν decay channel, resulting in an overall observed significance of 6.5 standard deviations and μggF + VBF + VH = 1. 16− 0.15 + 0.16(stat.)− 0.15 + 0.18(sys.). The results are interpreted in terms of scaling factors of the Higgs boson couplings to vector bosons (κV ) and fermions (κF ); the combined results are: |κV| = 1.06− 0.10 + 0.10, |κF| = 0. 85− 0.20 + 0.26.[Figure not available: see fulltext.] © 2015, The Author(s).
2015
Study of (W/Z)H production and Higgs boson couplings using H→ W W∗ decays with the ATLAS detector / Aad, G; Aloisio, Alberto; Alviggi, Mariagrazia; Canale, Vincenzo; DELLA VOLPE, Domenico; Merola, Leonardo; Conventi, Francesco; DELLA PIETRA, Massimo; Giordano, Raffaele; Perrella, Sabrina; Rossi, Elvira; Cirotto, Francesco; SANCHEZ PINEDA, ARTURO RODOLFO; Carlino, Gianpaolo; DE ASMUNDIS, Riccardo; DI DONATO, Camilla; Doria, Alessandra; Iengo, Paolo; Izzo, Vincenzo; Sekhniaidze, Givi; Et, A. l.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - 2015:8(2015). [10.1007/JHEP08(2015)137]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11588/636309
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