Abstract

The rate for Higgs (H) bosons production in association with either one (tH) or two ($\mathrm{t\bar{t}}$H) top quarks is measured in final states containing multiple electrons, muons, or tau leptons decaying to hadrons and a neutrino, using proton-proton collisions recorded at a center-of-mass energy of 13 TeV by the CMS experiment. The analyzed data correspond to an integrated luminosity of 137 fb$^{-1}$. The analysis is aimed at events that contain H $\to$ WW, H $\to$$\tau\tau$, or H $\to$ ZZ decays and each of the top quark(s) decays either to lepton+jets or all-jet channels. Sensitivity to signal is maximized by including ten signatures in the analysis, depending on the lepton multiplicity. The separation among the tH, the $\mathrm{t\bar{t}}$H, and the backgrounds is enhanced through machine-learning techniques and matrix-element methods. The measured production rates for the $\mathrm{t\bar{t}}$H and tH signals correspond to 0.92 $\pm$ 0.19 (stat) $^{+0.17}_{-0.13}$ (syst) and 5.7 $\pm$ 2.7 (stat) $\pm$ 3.0 (syst) of their respective standard model (SM) expectations. The corresponding observed (expected) significance amounts to 4.7 (5.2) standard deviations for $\mathrm{t\bar{t}}$H, and to 1.4 (0.3) for tH production. Assuming that the Higgs boson coupling to the tau lepton is equal in strength to its expectation in the SM, the coupling $y_{\mathrm{t}}$ of the Higgs boson to the top quark divided by its SM expectation, $\kappa_\mathrm{t}$ = $y_\mathrm{t} / y_\mathrm{t}^\mathrm{SM}$, is constrained to be within $-$0.9 $\lt$$\kappa_\mathrm{t}$$\lt$$-$0.7 or 0.7 $\lt$$\kappa_\mathrm{t}$$\lt$ 1.1, at 95% confidence level. This result is the most sensitive measurement of the $\mathrm{t\bar{t}}$H production rate to date.

Table 6

Table 6

10.17182/hepdata.100163.v2/t1

Number of events selected in the $3\ell$- and $4\ell$-CRs and in the CR for the ttW background, compared to the...
Table 7

Table 7

10.17182/hepdata.100163.v2/t2

Summary of the sources of systematic and statistical uncertainties and their impact on the measurement of the ttH and tH...
Table 8 1

Table 8

10.17182/hepdata.100163.v2/t3

Number of events selected in the 2$\ell$ss+0$\tau_{\mathrm{h}}$, 3$\ell$+0$\tau_{\mathrm{h}}$, and 2$\ell$ss+1$\tau_{\mathrm{h}}$ analysis channels compared to the event yields expected from the...
Table 8 2

Table 8

10.17182/hepdata.100163.v2/t4

Number of events selected in the 1$\ell$+1$\tau_{\mathrm{h}}$, 0$\ell$+2$\tau_{\mathrm{h}}$, 2$\ell$os+1$\tau_{\mathrm{h}}$, and 1$\ell$+2$\tau_{\mathrm{h}}$ analysis channels compared to the event yields expected from...
Table 8 3

Table 8

10.17182/hepdata.100163.v2/t5

Number of events selected in the 4$\ell$+0$\tau_{\mathrm{h}}$, 3$\ell$+1$\tau_{\mathrm{h}}$, and 2$\ell$+2$\tau_{\mathrm{h}}$ analysis channels compared to the event yields expected from the...
Figure 17

Figure 17

10.17182/hepdata.100163.v2/t6

Dependence of the likelihood function L as a function of $\kappa_{\mathrm{t}}$ and $\kappa_{\mathrm{V}}$.
Figure 15 - ttH tH

Figure 15

10.17182/hepdata.100163.v2/t7

$-2\Delta log( L)$ as a function of the production rate of ttH and tH.
Figure 15 - ttH ttW

Figure 15

10.17182/hepdata.100163.v2/t8

$-2\Delta log( L)$ as a function of the production rate of ttH and ttW.
Figure 15 - ttH ttZ

Figure 15

10.17182/hepdata.100163.v2/t9

$-2\Delta log( L)$ as a function of the production rate of ttH and ttZ.
Figure 15 - ttW ttZ

Figure 15

10.17182/hepdata.100163.v2/t10

$-2\Delta log( L)$ as a function of the production rate of ttW and ttZ.
Covariance matrix

10.17182/hepdata.100163.v2/t11

Covariance matrix of the fitted parameters of interest.
Figure 14 (ttH)

Figure 14

10.17182/hepdata.100163.v2/t12

Production rate of the ttH signal measured in each of the ten channels individually and for the combination of all...
Figure 14 (tH)

Figure 14

10.17182/hepdata.100163.v2/t13

Production rate of the tH signal measured in each of the ten channels individually and for the combination of all...
ttH acceptance

10.17182/hepdata.100163.v2/t14

Probability for ttH signal events to pass the event selection in each of the analysis categories employed.

Table 6

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Table 8 1

Table 8 2

Table 8 3

Figure 17

Figure 15 - ttH tH

Figure 15 - ttH ttW

Figure 15 - ttH ttZ

Figure 15 - ttW ttZ

Covariance matrix

Figure 14 (ttH)

Figure 14 (tH)

ttH acceptance

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