Higgs production in association with a single top quark at the LHC

Abstract

We present a detailed study of Higgs boson production in association with a single top quark at the LHC, at next-to-leading order accuracy in QCD. We consider total and differential cross sections, at the parton level as well as by matching short distance events to parton showers, for both t-channel and s-channel production. We provide predictions relevant for the LHC at 13 TeV together with a thorough evaluation of the residual uncertainties coming from scale variation, parton distributions, strong coupling constant and heavy quark masses. In addition, for t-channel production, we compare results as obtained in the 4-flavour and 5-flavour schemes, pinning down the most relevant differences between them. Finally, we study the sensitivity to a non-standard-model relative phase between the Higgs couplings to the top quark and to the weak bosons.

Heavy charged Higgs boson production at the LHC

“…in the MSSM. As will be shown, our analysis confirms and extends the conclusions that have been drawn in previous studies of differential distributions in the four-and fiveflavour schemes, in the context of Higgs production in association with bottom quarks [31], and Higgs and single-top associated production [32]. Similar analyses were performed for single top production [33,34].…”

“…Above that value, secondary g → bb splittings from hard gluons become more relevant, which is also reflected in the growth of the 5FS uncertainty band and K-factor. A similar behaviour has been observed in the case of tH production in the SM [32]. The pseudo-rapidity of the hardest…”

“…A similar behaviour was observed also in ref. [32] and it was explained by considering the different colour structure of the initial state in the two schemes, besides the fact that the process is generally harder in the 4FS. This tendency is slightly reduced -and as a consequence the agreement slightly improves -by the choice of a smaller shower scale (F = 4).…”

Is there room forCPviolation in the top-Higgs sector?

“…Despite the vast literature on top-gluon [5][6][7][8][9][10][11][12][13][14][15][16], top-photon [17][18][19][20][21], top-W [22][23][24][25][26][27][28], top Yukawa [29][30][31][32][33][34][35][36] couplings, and global analyses [37][38][39][40][41][42], the impact of electric dipole moments (EDMs) has received comparatively little attention [17,29,37,43,44]. The central new element of our work is the systematic inclusion of EDM constraints.…”

Measuring the signal strength intt¯HwithH→bbMoretti1, Petrov2, Pozzorini3 et al. 2016Phys. Rev. D130130View full textAdd to dashboardCite

“…While the loop-induced gg → H and H → γγ processes are sensitive to c t , direct access can only be obtained by measuring the production cross section of the Higgs boson in association with top quarks, e.g. ttH or tH, with the former having a seven times larger cross section in the Standard Model [14][15][16][17]. Hence, for the quality of a global fit of Higgs boson properties a precise measurement of c t through ttH production is indispensable.…”