ATLAS

Exotics@UCL

One of the key objectives of the Large Hadron Collider is the search for Physics beyond the Standard Model (SM). Operating at the energy frontier the LHC is in a unique place for such searches. UCL has a leading involvement in an a number of areas:

• New physics can be a resonance manifest as a localize increase of events over a smoothly falling background. The UCL team is searching for resonances in a variety of jet topologies with focusing on the most energetic Gauge (W, Z) bosons, Higgs bosons, and jets with a focus on b-hadon decays, our speciality. UCL pioneered X->bb and X->HH->bbbb searches.
• New physics can also be manifest as a general excess of events over a broad region. The UCL team has searched for non-resonant physics in dijet events and iniated the hunt for an enhanced rate of non-resonant SM HH->bbbb, one of the most important processes to measure in the HL-LHC program.
• The nature of dark matter (DM) is one of the great mysteries and pressing question of our time. The UCL team is looking for the production of dark matter particles at the LHC as well as mediators resonances that couple DM to SM particles.
• Particles like DM couple very weakly, this can lead to long-lived particles with a spectacular signature decaying in the outer parts of the ATLAS detector.
• Rather than designing dedicated searches, the hunt can also be tackled by making precision measurements and evaluating the potential impact of BSM physics on them, compared to SM expectations. UCL leads an effort to recast SM measurements to this purpose, using a package we developed called Contur. We also make these measurements! (See Standard Model@UCL.)

Key Academics

Jon Butterworth
Mario Campanelli
Nikos Konstantinidis
Andreas Korn
Tim Scanlon

Leadership positions

Gabriel Facini Exotics Group Convener 2016-2018
Katherine Leney Leptons, Z', W' and LFV Subgroup Convener 2015-2017
Gabriel Facini Jets and Dark Matter Subgroup Convener 2015-2016

Key References

• J. M. Butterworth, H. Debnath, P. Fileviez Perez, Y. Yeh Dark Matter from Anomaly Cancellation at the LHC
  arXiv:2405.03749
• J. M. Butterworth, H. Debnath, P. Fileviez Perez, F. Mitchell Custodial Symmetry Breaking and Higgs Signatures at the LHC
  arXiv:2309.10027 (Accepted by PRD.)
• GAMBIT Collaboration, Collider constraints on electroweakinos in the presence of a light gravitino
  Eur.Phys.J.C 83 (2023) 6, 493
• J. M. Butterworth, J. Heeck, Si Hyun Jeon, O. Mattelaer, R. Ruiz Testing the scalar triplet solution to CDF's heavy W problem at the LHC
  Phys.Rev.D 107 (2023) 7, 075020
• M. M. Altakach, J. M. Butterworth, T. Jezo, M. Klasen, I. Schienbein Probing a leptophobic top-colour model with cross section measurements and precise signal and background predictions
  SciPost Phys.Core 6 (2023) 1, 014
• B.C. Allanach, J.M. Butterworth, T. Corbett Large hadron collider constraints on some simple Z′Z′ models for b→sμ+μ−b→sμ+μ− anomalies
  Eur.Phys.J.C 81 (2021) 12, 1126
• J. M. Butterworth, L. Corpe, X. Kong, S. Kulkarni, M. Thomas New sensitivity of LHC measurements to composite dark matter models Phys.Rev.D 105 (2022) 1, 015008
• S. Amrith, J. M. Butterworth, F. F. Deppisch, W. Liu, A. Varma, D. Yallup, LHC Constraints on a B-L Gauge Model using Contur
  JHEP 1905 (2019) 154
• ATLAS Collaboration, Search for heavy resonances decaying into a W or Z boson and a Higgs boson in final states with leptons and b-jets in 36 fb-1 of sqrt(s)=13 TeV pp collisions with the ATLAS detector arXiv:1712.06518 or here
  
• ATLAS Collaboration, Search for diboson resonances with boson-tagged jets in pp collisions at sqrt(13) TeV with the ATLAS detectorarXiv:1708.04445 or Phys. Lett. B 777 (2017) 91
  
• ATLAS Collaboration, Search for heavy resonances decaying to a W or Z boson and a Higgs boson in the qqbb final state in pp collisions at sqrt(s)=13 TeV with the ATLAS detector arXiv:1707.06958 or Phys. Lett. B 774 (2017) 494
  
• ATLAS Collaboration, Search for new phenomena in dijet events using 37 fb−1 of pp collision data collected at √s=13 TeV with the ATLAS detector arXiv:1703.09127 or Phys. Rev. D 96, 052004 (2017)
  
• ATLAS Collaboration, Searches for heavy diboson resonances in pp collisions at sqrt(s)=13 TeV with the ATLAS detectorarXiv:1606.04833 or J. High Energ. Phys. (2016) 2016: 173.
  
• J. M. Butterworth, D. Grellscheid, M. Kramer, B. Sarrazin, D. Yallup, Constraining new physics with collider measurements of Standard Model signatures arxiv:1606.05296, JHEP 03 (2017) 078
  
• ATLAS Collaboration, Search for pair production of Higgs bosons in the bbbb final state using proton--proton collisions at sqrt(s)=13 TeV with the ATLAS detector arXiv:1606.04782 or Phys.Rev. D94 (2016) 052002
  
• ATLAS Collaboration, Search for resonances in the mass distribution of jet pairs with one or two jets identified as b-jets in proton--proton collisions at sqrt(s)=13 TeV with the ATLAS detector arXiv:1603.08791 or Phys.Lett. B759 (2016) 229-246
  
• ATLAS Collaboration, Search for new phenomena in dijet mass and angular distributions from pp collisions at √s=13 TeV with the ATLAS detector arXiv:1512.01530 or Physics Letters B 754 (2016) 302-322
  
• David Wardrope, Eric Jansen, Nikos Konstantinidis, Ben Cooper, Rebecca Falla, Nurfikri Norjoharuddeen, Non-resonant Higgs pair production in the bbbb final state at the LHC arXiv:1410.2794 or Eur.Phys.J. C75 (2015) 219
  
• Ben Cooper, Nikos Konstantinidis, Luke Lambourne, David Wardrope, Boosted hh->bbbb: a new topology in searches for TeV-scale resonances at the LHC
  arXiv:1307.0407 or Phys.Rev. D88 (2013) 114005
  
• Full list of ATLAS Exotics Results