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 uri icon

abstract

  • Abstract 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 c a up to 6 mm and has a mass in the range of 2060 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 $$ sqrt{s}=13 $$ 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 fb1. 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 m a = 20 GeV to 1.3 pb for m a = 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 c a 0.4 mm.

altmetric score

  • 3.1

author list (cited authors)

  • Aaboud, M., Aad, G., Abbott, B., Abdinov, O., Abeloos, B., Abhayasinghe, D. K., ... Zwalinski, L.

citation count

  • 24

complete list of authors

  • Aaboud, M||Aad, G||Abbott, B||Abdinov, O||Abeloos, B||Abhayasinghe, DK||Abidi, SH||AbouZeid, OS||Abraham, NL||Abramowicz, H||Abreu, H||Abulaiti, Y||Acharya, BS||Adachi, S||Adamczyk, L||Adelman, J||Adersberger, M||Adiguzel, A||Adye, T||Affolder, AA||Afik, Y||Agheorghiesei, C||Aguilar-Saavedra, JA||Ahmadov, F||Aielli, G||Akatsuka, S||Åkesson, TPA||Akilli, E||Akimov, AV||Alberghi, GL||Albert, J||Albicocco, P||Alconada Verzini, MJ||Alderweireldt, S||Aleksa, M||Aleksandrov, IN||Alexa, C||Alexopoulos, T||Alhroob, M||Ali, B||Alimonti, G||Alison, J||Alkire, SP||Allaire, C||Allbrooke, BMM||Allen, BW||Allport, PP||Aloisio, A||Alonso, A||Alonso, F||Alpigiani, C||Alshehri, AA||Alstaty, MI||Alvarez Gonzalez, B||Álvarez Piqueras, D||Alviggi, MG||Amadio, BT||Amaral Coutinho, Y||Ambroz, L||Amelung, C||Amidei, D||Amor Dos Santos, SP||Amoroso, S||Amrouche, CS||Anastopoulos, C||Ancu, LS||Andari, N||Andeen, T||Anders, CF||Anders, JK||Anderson, KJ||Andreazza, A||Andrei, V||Anelli, CR||Angelidakis, S||Angelozzi, I||Angerami, A||