Lifting degeneracies in Higgs couplings using single top production in association with a Higgs boson

By M. Farina, Christophe Grojean, Fabio Maltoni, E. Salvioni, A. Thamm. 2012

137 citations recorded by the source corpus.

A bstractCurrent Higgs data show an ambiguity in the value of the Yukawa couplings to quarks and leptons. Not so much because of still large uncertainties in the measurements but as the result of several almost degenerate minima in the coupling profile likelihood function. To break these degeneracies, it is important to identify and measure processes where the Higgs coupling to fermions interferes with other coupling(s). The most prominent example, the decay of h → γγ, is not sufficient to give a definitive answer. In this paper, we argue that t-channel single top production in association with a Higgs boson, with h → bb, can provide the necessary information to lift the remaining degeneracy in the top Yukawa. Within the Standard Model, the total rate is highly reduced due to an almost perfect destructive interference in the hard process, W b → th. We first show that for non-standard couplings the cross section can be reliably computed without worrying about corrections from physics beyond the cutoff scale Λ ≳ 10 TeV, and that it can be enhanced by more than one order of magnitude compared to the SM. We then study the signal pp → thj(b) with 3 and 4 b’s in the final state, and its main backgrounds at the LHC. We find the 8 TeV run dataset to be sensitive to the sign of the anomalous top Yukawa coupling, while already a moderate integrated luminosity at 14 TeV should lift the degeneracy completely.

Subfields: Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/6c358c9af995016d397c01a92917fe8e6c99265e

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Nuclear and High Energy Physics

Citations in the corpus

Constraining anomalous Higgs boson couplings to the heavy flavor fermions using matrix element techniques (2016, methodology): “There has been considerable effort in modeling the Hff̄ couplings and developing tools for their analysis in associated production [8–31] and in the H → τ+τ− decay [32–38].”
Physics at a 100 TeV pp collider: Higgs and EW symmetry breaking studies (2016, background): “This remarkable growth, together with the sensitivity of this process to the sign of the top Yukawa coupling yt [139], makes this reaction a golden channel for a precise measurement of the latter.”
Measurements of the Higgs boson production and decay rates and coupling strengths using pp collision data at \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\o (2015, unknown): “the four-ﬂavour scheme and up to NNLO [66] in the ﬁve-ﬂavour scheme with the Santander matching scheme [67]. The cross sections of the tH processes used are calculated at up to NLO in QCD corrections [68,69]. The PDF sets used in these calculations are CT10 [70,71], MSTW2008 [72], NNPDF2.1 [73,74] a”
Mass effects in the Higgs-gluon coupling: boosted vs. off-shell production (2014, background): “Its measurement from associated Higgs and top pair production with a proper reconstruction of the three heavy states is challenging [25–37].”
Effective Lagrangian for a light Higgs-like scalar (2013, background): “Furthermore, we stress that in order to distinguish the effect of OtG from that of Og, the tt̄h channel should be measured [69] (single top production in association with the Higgs could also provide complementary information [85]).”
Higgs boson self-coupling measurements using ratios of cross sections (2013, background): “cy with respect to the sign of y t that appears in Higgs pair production may be resolved through the study of dierent processes long before the Higgs self-coupling is probed. See, for example, Refs. [69,70]. { 9 { that going beyond 300 fb 1 of luminosity, there will be no improvement on these uncert”
Higgs boson pair production in the D = 6 extension of the SM (2014, background): “[104], gg → hh could also help to lift the degeneracy, in which case the EFT expansion needs to be performed around the non-SM minima of interest.”