Enhancing the tt̄H signal through top-quark spin polarization effects at the LHC

Summary, in English

We compare the impact of top-quark spin polarization effects in Higgs boson production in association with top-quark pairs and in corresponding backgrounds at the LHC. Because of the spin-zero nature of the Higgs boson, one expects, in the chiral limit for the top quarks, a substantial complementarity in tt̄ spin correlations for a Higgs decaying into fermions/gauge-bosons and tt̄ spin correlations for the corresponding irreducible tt̄ff̄/V V backgrounds. Although top mass effects in tt̄H production are in general dominant, and seriously spoil the chiral-limit expectations, one can find observables that capture the tt̄ angular spin correlations and can help in separating the signal from irreducible backgrounds. In particular, we show that, for both H → bb̄ and H → γγ, taking into account tt̄ spin correlations in tt̄H production and irreducible backgrounds could appreciably improve the LHC sensitivity to the tt̄H channel.

• Author: S. Biswas; R. Frederix; E. Gabrielli; B. Mele
• Publishing year: 2014-07
• Language: English
• Publication/Series: Journal of High Energy Physics
• Volume: 2014
• Issue: 7
• Links: http://dx.doi.org/10.1007/JHEP07(2014)020
• Document type: Journal article
• Publisher: Springer
• Topic: Subatomic Physics
• Keywords: Heavy quark physics; Higgs physics
• Status: Published
• ISBN/ISSN/Other: ISSN: 1029-8479