Franklin, MelissaHuth, JohnMorii, Masahiro2023-06-232018-04ATLAS Collaboration. "A search for resonances decaying into a Higgs boson and a new particle X in the XH → qqbb final state with the ATLAS detector." Phys Lett B, 2018. (ATLAS Collab. )0370-2693https://nrs.harvard.edu/URN-3:HUL.INSTREPOS:37376161A search for heavy resonances decaying into a Higgs boson (H) and a new particle (X) is reported, utilizing 36.1 fb−1 of proton–proton collision data at √s = 13 TeV collected during 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. The particle X is assumed to decay to a pair of light quarks, and the fully hadronic final state XH → qq ̄′bb ̄ is analysed. The search considers the regime of high XH resonance masses, where the X and H bosons are both highly Lorentz-boosted and are each reconstructed using a single jet with large radius parameter. A two-dimensional phase space of XH mass versus X mass is scanned for evidence of a signal, over a range of XH resonance mass values between 1 TeV and 4 TeV, and for X particles with masses from 50 GeV to 1000 GeV. All search results are consistent with the expectations for the background due to Standard Model processes, and 95% CL upper limits are set, as a function of XH and X masses, on the production cross-section of the XH → qq ̄′bb ̄ resonance.en-USNuclear and High Energy PhysicsJournal Article2018-07-1820182023-06-2310.1016/j.physletb.2018.01.042