A search for resonances decaying into a Higgs boson and a new particle X in the XH → qqbb final state with the ATLAS detector

Summary, in English

A 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=13TeV 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.

• Author: Aaboud M.; T. Åkesson; S. Bocchetta; E. Corrigan; C. Doglioni; V. Hedberg; G. Jarlskog; C. Kalderon; E. Kellermann; B. Konya; E. Lytken; K. Mankinen; U. Mjörnmark; R. Poettgen; T. Poulsen; O. Smirnova; O. Viazlo; Zwalinski L.
• Department/s: Particle and nuclear physics; eSSENCE: The e-Science Collaboration
• Publishing year: 2018
• Language: English
• Pages: 24-45
• Publication/Series: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
• Volume: 779
• Links: http://dx.doi.org/10.1016/j.physletb.2018.01.042
• Document type: Journal article
• Publisher: Elsevier
• Topic: Subatomic Physics
• Status: Published
• ISBN/ISSN/Other: ISSN: 0370-2693