TY - JOUR
T1 - Search for the Higgs boson produced in association with a vector boson and decaying into two spin-zero particles in the H -> aa -> 4b channel in pp collisions at root s=13 TeV with the ATLAS detector
AU - Aaboud, M.
AU - Aad, G.
AU - Abbott, B.
AU - Abdinov, O.
AU - Abeloos, B
AU - Abhayasinghe, DK
AU - Abidi, S.H.
AU - Abouzeid, Ossama Sherif Alexander
AU - Abraham, NL
AU - Abramowicz, H.
AU - Abreu, H.
AU - Abulaiti, Y.
AU - Acharya, B.S.
AU - Adachi, Sosuke
AU - Adamczyk, L.
AU - Adelman, J.
AU - Adersberger, M.
AU - Adiguzel, A.
AU - Adye, T.
AU - Affolder, A. A.
AU - Afik, Y.
AU - Agheorghiesei, C.
AU - Aguilar-Saavedra, J. A.
AU - Ahmadov, F.
AU - Alonso Diaz, Alejandro
AU - Besjes, Geert-Jan
AU - Bajic, Milena
AU - Dam, Mogens
AU - de Almeida Dias, Flavia
AU - Hansen, Jørgen Beck
AU - Galster, Gorm Aske Gram Krohn
AU - Hansen, Peter Henrik
AU - Hansen, Jørn Dines
AU - Thiele, Fabian Alexander Jürgen
AU - Stark, Simon Holm
AU - Monk, James William
AU - Petersen, Troels Christian
AU - Wiglesworth, Graig
AU - Xella, Stefania
PY - 2018/10/1
Y1 - 2018/10/1
N2 - A search for exotic decays of the Higgs boson into a pair of spin-zero particles, H → aa, where the a-boson decay sin to b-quarks promptly or with a mean proper lifetime cτa up to 6 mm and has a mass in the range of 20–60 GeV, is presented. The search is performed in events where the Higgs boson is produced in association with a W or Z boson, giving rise to a signature of one or two charged leptons (electrons or muons) and multiple jets from b-quark decays. The analysis is based on the dataset of proton-proton collisions at s=13 TeV recorded in 2015 and 2016 by the ATLAS detector at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb−1. No significant excess of events above the Standard Model background prediction is observed, and 95% confidence-level upper limits are derived for the production cross-sections for pp → WH, ZH and their combination, times the branching ratio of the decay chain H → aa → 4b. For a-bosons which decay promptly, the upper limit on the combination of cross-sections for WH and ZH times the branching ratio of H → aa → 4b ranges from 3.0 pb for ma = 20 GeV to 1.3 pb for ma = 60 GeV, assuming that the ratio of WH to ZH cross-sections follows the Standard Model prediction. For a-bosons with longer proper lifetimes, the most stringent limits are 1.8 pb and 0.68 pb, respectively, at cτa ∼ 0.4 mm.[Figure not available: see fulltext.].
AB - A search for exotic decays of the Higgs boson into a pair of spin-zero particles, H → aa, where the a-boson decay sin to b-quarks promptly or with a mean proper lifetime cτa up to 6 mm and has a mass in the range of 20–60 GeV, is presented. The search is performed in events where the Higgs boson is produced in association with a W or Z boson, giving rise to a signature of one or two charged leptons (electrons or muons) and multiple jets from b-quark decays. The analysis is based on the dataset of proton-proton collisions at s=13 TeV recorded in 2015 and 2016 by the ATLAS detector at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb−1. No significant excess of events above the Standard Model background prediction is observed, and 95% confidence-level upper limits are derived for the production cross-sections for pp → WH, ZH and their combination, times the branching ratio of the decay chain H → aa → 4b. For a-bosons which decay promptly, the upper limit on the combination of cross-sections for WH and ZH times the branching ratio of H → aa → 4b ranges from 3.0 pb for ma = 20 GeV to 1.3 pb for ma = 60 GeV, assuming that the ratio of WH to ZH cross-sections follows the Standard Model prediction. For a-bosons with longer proper lifetimes, the most stringent limits are 1.8 pb and 0.68 pb, respectively, at cτa ∼ 0.4 mm.[Figure not available: see fulltext.].
U2 - 10.1007/JHEP10(2018)031
DO - 10.1007/JHEP10(2018)031
M3 - Journal article
SN - 1126-6708
VL - 2018
JO - Journal of High Energy Physics
JF - Journal of High Energy Physics
IS - 10
M1 - 031
ER -