Physics and Astronomy » High Energy Physics »


20 Jan 2018


The Higgs boson was discovered via its decays to bosons by the ATLAS and CMS collaborations in 2012 and has since been observed in decays to tau leptons. It has however not directly been observed coupling to the quark sector, which includes its largest decay to a pair of b-quarks. To fully probe the new particle it is vital to directly observe its coupling to quarks and to precisely measure its decay to b-quarks. UCL pioneered this decay channel and has since played a leading role in probing the Higgs sector via the decay of the Higgs to a pair of b-quarks. Despite the large branching ratio, this is a very challenging channel, which requires great understanding of the complex and large background processes. However, studying this channel is vital to fully understand the nature of the Higgs boson disocvered at the LHC and to unravel the mysteries surrounding the Higgs sector.

Key Academics

Jon Butterworth
Gavin Hesketh
Tim Scanlon

Leadership Positions

Tim Scanlon - ATLAS H->bb Subgroup Covener 2016-2017

Key References

  • J. Butterworth, A. Davidson, M. Rubin, G. Salam, Jet substructure as a new Higgs search channel at the LHC
    Phys.Rev.Lett. 100 (2008) 242001

  • ATLAS Collaboration, Search for the bb decay of the Standard Model Higgs boson in associated (W/Z)H production with the ATLAS detector
    JHEP 1501 (2015) 069

  • J. Butterworth, , Boosted Higgs→bb in vector-boson associated production at 14 TeV
    Eur.Phys.J. C75 (2015) no.8, 366

  • ATLAS Collaboration, Search for the Standard Model Higgs boson produced in association with a vector boson and decaying to a bb pair in pp collisions at 13 TeV using the ATLAS detector

    A candidate Higgs Event decaying to two b-quarks produced in association with a Z boson, decaying to two muons, from the ATLAS detector.