Combined measurements and interpretations of Higgs boson production and decay in proton-proton collisions at $\sqrt{s}$ = 13 TeV

Abstract

Combined measurements of Higgs boson production and decay rates are reported, representing the most comprehensive study performed by the CMS Collaboration to date. The included analyses use proton-proton collision data recorded by the CMS experiment at $\sqrt{s}$ = 13 TeV from 2016 to 2018, corresponding to an integrated luminosity of 138 fb$^{-1}$. The statistical combination is based on analyses that measure the following decay channels: H $\to$ $γγ$, H $\to$ ZZ, H $\to$ WW, H $\to$ $ττ$, H $\to$ bb, H $\to$ $μμ$, and H $\to$ Z$γ$ $\to$ $\ell\ellγ$ ($\ell$ = e,$μ$). Information in the events from each decay channel is used to target multiple Higgs boson production processes. Searches for invisible Higgs boson decays are also considered, as well as an analysis that measures off-shell Higgs boson production in the H $\to$ ZZ $\to$ 4$\ell$ decay channel. The best fit inclusive signal yield is measured to be 1.014$^{+0.055}_{-0.053}$ times the standard model expectation, for a Higgs boson mass of 125.38 GeV. Measurements in kinematic regions defined by the simplified template cross section framework are also provided, as well as interpretations in the coupling modifier and standard model effective field theory frameworks. The coupling modifier interpretation is further used to place constraints on various two-Higgs-doublet models. The results show good compatibility with the standard model predictions for the majority of the measured parameters.

Figures (30)

• Figure 1: Examples of leading-order Feynman diagrams for the ${ \mathup{{{H}}{} _{ {}} ^{ {}}} }\xspace\to{ \mathup{{{Z}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{Z}}{} _{ {}} ^{ {}}} }\xspace$ and ${ \mathup{{{H}}{} _{ {}} ^{ {}}} }\xspace\to{ \mathup{{{W}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{W}}{} _{ {}} ^{ {}}} }\xspace$ decay channels (upper left); for the ${ \mathup{{{H}}{} _{ {}} ^{ {}}} }\xspace\to{ \mathup{{{b}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{b}}{} _{ {}} ^{ {}}} }\xspace$, ${ \mathup{{{H}}{} _{ {}} ^{ {}}} }\xspace\to{ \mathup{{{\uptau}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{\uptau}}{} _{ {}} ^{ {}}} }\xspace$, and ${ \mathup{{{H}}{} _{ {}} ^{ {}}} }\xspace\to{ \mathup{{{\upmu}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{\upmu}}{} _{ {}} ^{ {}}} }\xspace$ decay channels (upper right); and for the ${ \mathup{{{H}}{} _{ {}} ^{ {}}} }\xspace\to{ \mathup{{{\upgamma}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{\upgamma}}{} _{ {}} ^{ {}}} }\xspace$ and ${ \mathup{{{H}}{} _{ {}} ^{ {}}} }\xspace\to{ \mathup{{{Z}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{\upgamma}}{} _{ {}} ^{ {}}} }\xspace$ decay channels (lower).
• Figure 2: Examples of leading-order Feynman diagrams for the $\mathrm{ggH}$ (upper left), $\mathrm{VBF}$ (upper middle), quark-initiated $\mathrm{VH}$ (upper right), gluon-initiated $\mathrm{ZH}$ (middle left), $\mathrm{ttH}$ and $\mathrm{bbH}$ (middle right), ${ \mathup{{{t}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{H}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{q}}{} _{ {}} ^{ {}}} }\xspace$ (lower left), and ${ \mathup{{{t}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{H}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{W}}{} _{ {}} ^{ {}}} }\xspace$ (lower right) processes.
• Figure 3: Breakdown of the 68% $\text{CL}$ intervals on the best fit inclusive and per production process (left), and per decay channel (right) signal strength modifiers, for the different sources of uncertainty. The uncertainty contributions are shown as percentages relative to the best fit signal strength values. All contributions are symmetrized by taking the average of the upward and downward fluctuations. The "Misc." label absorbs all other uncertainty contributions not listed explicitly in the figure. The NPs from each uncertainty source are sequentially fixed to their best fit values to derive the individual contributions following the order in which they are shown in the figure. The total uncertainty is shown by the dashed red boxes, while the combined systematic uncertainties from experimental and theoretical components are shown in orange and purple, respectively. The uncertainties for the $\mu^{\mathrm{tH}\xspace}$, $\mu^{{ \mathup{{{\upmu}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{\upmu}}{} _{ {}} ^{ {}}} }\xspace\xspace}$, and $\mu^{{ \mathup{{{Z}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{\upgamma}}{} _{ {}} ^{ {}}} }\xspace\xspace}$ parameters are multiplied by a factor of 0.5.
• Figure 4: The measured inclusive ($\mu^{\text{incl}}$) and per production process ($\mu^i$) signal strength modifiers. In the upper plot, the thick (thin) black lines indicate the 68% (95%) $\text{CL}$ intervals, with the theoretical systematic, experimental systematic, and statistical components of the 68% intervals indicated by the purple, orange, and blue bands, respectively. The grey band shows the 68% $\text{CL}$ interval on the inclusive signal strength modifier. A separate axis is provided for the $\mu^{\mathrm{tH}\xspace}$ parameter because of its larger uncertainty and high best fit value. The correlations between the 6 parameters in the per production process measurement are shown in the lower plot. The size of the correlations is indicated by the colour scale.
• Figure 5: The measured per decay channel signal strength modifiers, $\mu^f$. In the upper plot, the thick (thin) black lines indicate the 68% (95%) $\text{CL}$ intervals, with the theoretical systematic, experimental systematic, and statistical components of the 68% intervals indicated by the purple, orange, and blue bands, respectively. The grey band shows the 68% $\text{CL}$ interval on the inclusive signal strength modifier. A separate axis is provided for the $\mu^{{ \mathup{{{Z}}{} _{ {}} ^{ {}}} }\xspace{ \mathup{{{\upgamma}}{} _{ {}} ^{ {}}} }\xspace\xspace}$ parameter because of its larger uncertainty and high best fit value. The correlations between the 7 parameters considered in this fit are shown in the lower plot. The size of the correlations is indicated by the colour scale.