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| CMS-HIG-18-016 ; CERN-EP-2018-223 | ||
| Observation of Higgs boson decay to bottom quarks | ||
| CMS Collaboration | ||
| 24 August 2018 | ||
| Phys. Rev. Lett. 121 (2018) 121801 | ||
| Abstract: The observation of the standard model (SM) Higgs boson decay to a pair of bottom quarks is presented. The main contribution to this result is from processes in which Higgs bosons are produced in association with a W or Z boson (VH), and are searched for in final states including 0, 1, or 2 charged leptons and two identified bottom quark jets. The results from the measurement of these processes in a data sample recorded by the CMS experiment in 2017, comprising 41.3 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} = $ 13 TeV, are described. When combined with previous VH measurements using data collected at $\sqrt{s}= $ 7, 8, and 13 TeV, an excess of events is observed at ${m_\mathrm{H}} = $ 125.09 GeV with a significance of 4.8 standard deviations, where the expectation for the SM Higgs boson is 4.9. The corresponding measured signal strength is 1.01 $\pm$ 0.22. The combination of this result with searches by the CMS experiment for ${\mathrm{H}\to\mathrm{b\bar{b}}}$ in other production processes yields an observed (expected) significance of 5.6 (5.5) standard deviations and a signal strength of 1.04 $\pm$ 0.20. | ||
| Links: e-print arXiv:1808.08242 [hep-ex] (PDF) ; CDS record ; inSPIRE record ; HepData record ; CADI line (restricted) ; | ||
| Figures & Tables | Summary | Additional Figures & Tables | References | CMS Publications |
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| Figures | |
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Figure 1:
Left: distributions of signal, background, and data event yields sorted into bins of similar signal-to-background ratio, as given by the result of the fit to their corresponding multivariate discriminant. All events in the VH, ${{\mathrm {H}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}}}$ signal regions of the combined Run 1 and Run 2 data sets are included. The red histogram indicates the Higgs boson signal contribution, while the grey histogram is the sum of all background yields. The bottom panel shows the ratio of the data to the background, with the total uncertainty in the background yield indicated by the grey hatching. The red line indicates the sum of signal plus background contribution divided by the background yield. Right: best-fit value of the signal strength $\mu $, at $ {m_ {\mathrm {H}}} = $ 125.09 GeV, for the fit of all VH, ${{\mathrm {H}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}}}$ channels in the Run 1 and Run 2 data sets. Also shown are the individual results of the 2016 and 2017 measurements, the Run 2 combination, and the Run 1 result. Horizontal error bars indicate the 1$\sigma $ systematic (red) and 1$\sigma $ total (blue) uncertainties, and the vertical dashed line indicates the SM expectation. |
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Figure 1-a:
Distributions of signal, background, and data event yields sorted into bins of similar signal-to-background ratio, as given by the result of the fit to their corresponding multivariate discriminant. All events in the VH, ${{\mathrm {H}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}}}$ signal regions of the combined Run 1 and Run 2 data sets are included. The red histogram indicates the Higgs boson signal contribution, while the grey histogram is the sum of all background yields. The bottom panel shows the ratio of the data to the background, with the total uncertainty in the background yield indicated by the grey hatching. The red line indicates the sum of signal plus background contribution divided by the background yield. |
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Figure 1-b:
Best-fit value of the signal strength $\mu $, at $ {m_ {\mathrm {H}}} = $ 125.09 GeV, for the fit of all VH, ${{\mathrm {H}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}}}$ channels in the Run 1 and Run 2 data sets. Also shown are the individual results of the 2016 and 2017 measurements, the Run 2 combination, and the Run 1 result. Horizontal error bars indicate the 1$\sigma $ systematic (red) and 1$\sigma $ total (blue) uncertainties, and the vertical dashed line indicates the SM expectation. |
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Figure 2:
Dijet invariant mass distribution for events weighted by $S/(S+B)$ in all channels combined in the 2016 and 2017 data sets. Weights are derived from a fit to the ${m\mathrm {(jj)}}$ distribution, as described in the text. Shown are data (points) and the fitted VH signal (red) and VZ background (grey) distributions, with all other fitted background processes subtracted. The error bar for each bin represents the pre-subtraction 1$\sigma $ statistical uncertainty on the data, while the grey hatching indicates the 1$\sigma $ total uncertainty on the signal and all background components. |
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Figure 3:
Best-fit value of the $ {{\mathrm {H}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}}} $ signal strength with its 1$\sigma $ systematic (red) and total (blue) uncertainties for the five individual production modes considered, as well as the overall combined result. The vertical dashed line indicates the standard model expectation. All results are extracted from a single fit combining all input analyses, with $ {m_ {\mathrm {H}}} = $ 125.09 GeV. |
| Tables | |
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Table 1:
Major sources of uncertainty in the measurement of the signal strength $\mu $, and their observed impact ($\Delta \mu $) from a fit to the 2017 data set, are listed. The total uncertainty is separated into four components: statistical (including data yields), experimental, MC sample size, and theory. Detailed decompositions of the statistical, experimental, and theory components are specified. The impact of each uncertainty is evaluated considering only that source. Because of correlations in the combined fit between nuisance parameters in different sources, the sum in quadrature for each source does not in general equal the total uncertainty of each component. |
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Table 2:
Expected and observed significances, in $\sigma $, and observed signal strengths for the VH production process with ${{\mathrm {H}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}}}$. Results are shown separately for 2017 data, combined Run 2 (2016 and 2017) data, and for the combination of the Run 1 and Run 2 data sets. For the 2017 analysis, results are shown separately for the individual signal strengths for each channel from a combined simultaneous fit to all channels. All results are obtained for $ {m_ {\mathrm {H}}} = $ 125.09 GeV combining statistical and systematic uncertainties. |
| Summary |
| In summary, measurement of the standard model Higgs boson decaying to bottom quarks has been presented. A combination of all CMS measurements of the VH, ${\mathrm{H}\to\mathrm{b\bar{b}}}$ process using proton-proton collisions recorded at center of mass energies of 7, 8, and 13 TeV, yields an observed (expected) significance of 4.8 (4.9) standard deviations at ${m_ {\mathrm {H}}} = $ 125.09 GeV, and the signal strength is $\mu = $ 1.01 $\pm$ 0.22. Combining this result with previous measurements by the CMS Collaboration of the ${\mathrm{H}\to\mathrm{b\bar{b}}}$ decay in events where the Higgs boson is produced through gluon fusion, vector boson fusion, or in association with top quarks, the observed (expected) significance increases to 5.6 (5.5) standard deviations and the signal strength is $\mu = $ 1.04 $\pm$ 0.20. This constitutes the observation of the ${\mathrm{H}\to\mathrm{b\bar{b}}}$ decay by the CMS Collaboration. |
| Additional Figures | |
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Additional Figure 1:
Dijet invariant mass distributions for simulated samples of ${{\mathrm {Z}}(\ell \ell) {\mathrm {H}} ({\mathrm {b}} {\mathrm {b}})}$ events ($m_{\mathrm{H}} = $ 125 GeV) without (left) and with one additional recoiling jet (right). Distributions are shown before (red) and after (blue) the energy corrections from the b-jet regression are applied, and when a kinematic fit procedure (green) is used on top of them. A Bukin function is used to fit the distribution. The fitted mean and width of the core of the distribution are displayed on the figure. |
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Additional Figure 1-a:
Dijet invariant mass distributions for simulated samples of ${{\mathrm {Z}}(\ell \ell) {\mathrm {H}} ({\mathrm {b}} {\mathrm {b}})}$ events ($m_{\mathrm{H}} = $ 125 GeV) without any additional recoiling jet. Distributions are shown before (red) and after (blue) the energy corrections from the b-jet regression are applied, and when a kinematic fit procedure (green) is used on top of them. A Bukin function is used to fit the distribution. The fitted mean and width of the core of the distribution are displayed on the figure. |
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Additional Figure 1-b:
Dijet invariant mass distributions for simulated samples of ${{\mathrm {Z}}(\ell \ell) {\mathrm {H}} ({\mathrm {b}} {\mathrm {b}})}$ events ($m_{\mathrm{H}} = $ 125 GeV) with one additional recoiling jet. Distributions are shown before (red) and after (blue) the energy corrections from the b-jet regression are applied, and when a kinematic fit procedure (green) is used on top of them. A Bukin function is used to fit the distribution. The fitted mean and width of the core of the distribution are displayed on the figure. |
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Additional Figure 2:
The best-fit signal strength and uncertainty per-channel and for the WH and ZH processes, extracted from a simultaneous fit of all channels for the 2017 analysis. The per-channel signal strengths are compatible with the single signal strength fit with a probability of 96.9%. |
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Additional Figure 3:
Dijet invariant mass distribution for events weighted by S/(S+B) in all channels combined in the 2016 and 2017 data sets. Weights are derived from a fit to the ${m_{\mathrm {(jj)}}}$ distribution, as described in the text. Shown are data (points) and the fitted VH signal (red) and VZ background (grey) distributions, as well as all other backgrounds. |
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Additional Figure 4:
Dijet invariant mass distribution for events weighted by S/(S+B) in all channels combined in the 2016 and 2017 data sets. Weights are derived from a fit to the ${m_{\mathrm {(jj)}}}$ distribution, as described in the text. Shown are data (points) and the fitted VH signal (red) and VZ background (grey) distributions, with all other fitted background processes subtracted. The error bar for each bin represents the pre-subtraction 1$\sigma $ statistical uncertainty on the data, while the grey hatching indicates the 1$\sigma $ total uncertainty on the signal and all background components. Same as in paper, but the VZ is on top. |
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Additional Figure 5:
Post-fit distributions of the Multi-background DNN fit variable for 2017 analysis in the 1-lepton channel (top row) for muon (left) and electron (right) control regions, and for the 0-lepton channel (bottom row). |
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Additional Figure 5-a:
Post-fit distributions of the Multi-background DNN fit variable for 2017 analysis in the 1-lepton channel for muon electron control region. Additional Figure 5-b |
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Additional Figure 5-b:
Post-fit distributions of the Multi-background DNN fit variable for 2017 analysis in the 1-lepton channel (top row) for muon (left) and electron (right) control regions, and for the 0-lepton channel (bottom row). |
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Additional Figure 5-c:
Post-fit distributions of the Multi-background DNN fit variable for 2017 analysis in the 1-lepton channel (top row) for muon (left) and electron (right) control regions, and for the 0-lepton channel (bottom row). |
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Additional Figure 6:
Post-fit distributions of the two fitted bins of ${\mathrm {DeepCSV_{min}}}$ in the 2-lepton Z+HF control regions. Above are the high ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ categories and below are the low ${{p_{\mathrm {T}}} ({\mathrm {V}})}$. The left shows the distributions for 2$\mu $ channels and on the right are the same for 2e channels. |
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Additional Figure 6-a:
Post-fit distributions of the two fitted bins of ${\mathrm {DeepCSV_{min}}}$ in the 2-lepton Z+HF control regions: high ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ category for the 2$\mu $ channel. |
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Additional Figure 6-b:
Post-fit distributions of the two fitted bins of ${\mathrm {DeepCSV_{min}}}$ in the 2-lepton Z+HF control regions: low ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ category for the 2e channel. |
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Additional Figure 6-c:
Post-fit distributions of the two fitted bins of ${\mathrm {DeepCSV_{min}}}$ in the 2-lepton Z+HF control regions: high ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ category for the 2$\mu $ channel. |
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Additional Figure 6-d:
Post-fit distributions of the two fitted bins of ${\mathrm {DeepCSV_{min}}}$ in the 2-lepton Z+HF control regions: low ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ category for the 2e channel. |
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Additional Figure 7:
Post-fit distributions of multivariate discriminator output channels for 2017 analysis, after all signal region pre-selection criteria have been applied. First row: 2-lepton muon (left) and electron (right) channel for high ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ region, in the second row the low ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ is shown. Third row: 1-lepton muon (left) and electron (right) channel. Fourth row: 0-lepton channel. |
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Additional Figure 7-a:
Post-fit distributions of multivariate discriminator output channels for 2017 analysis, after all signal region pre-selection criteria have been applied: 2-lepton muon channel for high ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ region. |
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Additional Figure 7-b:
Post-fit distributions of multivariate discriminator output channels for 2017 analysis, after all signal region pre-selection criteria have been applied: 2-lepton electron channel for high ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ region. |
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Additional Figure 7-c:
Post-fit distributions of multivariate discriminator output channels for 2017 analysis, after all signal region pre-selection criteria have been applied: 2-lepton muon channel for low ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ region. |
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Additional Figure 7-d:
Post-fit distributions of multivariate discriminator output channels for 2017 analysis, after all signal region pre-selection criteria have been applied: 2-lepton electron channel for low ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ region. |
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Additional Figure 7-e:
Post-fit distributions of multivariate discriminator output channels for 2017 analysis, after all signal region pre-selection criteria have been applied: 1-lepton muon channel. |
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Additional Figure 7-f:
Post-fit distributions of multivariate discriminator output channels for 2017 analysis, after all signal region pre-selection criteria have been applied: 1-lepton electron channel. |
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Additional Figure 7-g:
Post-fit distributions of multivariate discriminator output channels for 2017 analysis, after all signal region pre-selection criteria have been applied: 0-lepton channel. |
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Additional Figure 8:
Distributions of signal, background, and data event yields sorted into bins of similar signal-to-background ratio, as given by the result of the fit to their corresponding multivariate discriminant. All events in the 2017 VH, ${{\mathrm {H}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}}}$ signal regions are included on the left while the currently analyzed Run 2 data (2016+2017) are shown on the right. The red histogram indicates the Higgs boson signal contribution, while the grey histogram is the sum of all background yields. |
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Additional Figure 8-a:
Distributions of signal, background, and data event yields sorted into bins of similar signal-to-background ratio, as given by the result of the fit to their corresponding multivariate discriminant. All events in the 2017 VH, ${{\mathrm {H}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}}}$ signal regions are included. The red histogram indicates the Higgs boson signal contribution, while the grey histogram is the sum of all background yields. |
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Additional Figure 8-b:
Distributions of signal, background, and data event yields sorted into bins of similar signal-to-background ratio, as given by the result of the fit to their corresponding multivariate discriminant. The currently analyzed Run 2 data (2016+2017) are shown. The red histogram indicates the Higgs boson signal contribution, while the grey histogram is the sum of all background yields. |
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Additional Figure 9:
Distributions of signal, background, and data event yields sorted into bins of similar signal-to-background ratio, as given by the result of the fit to their corresponding multivariate discriminant. All events in the 2017 VZ, ${{\mathrm {Z}}\to {{\mathrm {b}} {\overline {\mathrm {b}}}}}$ signal regions are included. The red histogram indicates the ${{\mathrm {Z}}\to {{\mathrm {b}} {\overline {\mathrm {b}}}}} $ signal contribution, while the grey histogram is the sum of all background yields. |
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Additional Figure 10:
The two plots above show the top quark mass reconstructed in the 1-lepton ${{\mathrm {t}\overline {\mathrm {t}}}} $ control region using the tagged lepton, ${{p}_{\mathrm {T}}^{\text {miss}}}$, one of the two b-jets and the constraint of the W mass to estimate the longitudinal component of the neutrino. The reconstruction on the left uses the un-regressed b-jet energy and the right uses regressed b-jet energy. |
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Additional Figure 10-a:
The plot above shows the top quark mass reconstructed in the 1-lepton ${{\mathrm {t}\overline {\mathrm {t}}}} $ control region using the tagged lepton, ${{p}_{\mathrm {T}}^{\text {miss}}}$, one of the two b-jets and the constraint of the W mass to estimate the longitudinal component of the neutrino. The reconstruction uses the un-regressed b-jet energy. |
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Additional Figure 10-b:
The plot above shows the top quark mass reconstructed in the 1-lepton ${{\mathrm {t}\overline {\mathrm {t}}}} $ control region using the tagged lepton, ${{p}_{\mathrm {T}}^{\text {miss}}}$, one of the two b-jets and the constraint of the W mass to estimate the longitudinal component of the neutrino. The reconstruction uses the regressed b-jet energy. |
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Additional Figure 11:
All three figures above show the ratio of the di-jet ${p_{\mathrm {T}}}$ to the di-lepton (V) ${p_{\mathrm {T}}}$ in the 2-lepton HF control region. The b-jets in the left plot come directly from CMS reconstruction with charged hadron subtraction applied. The b-jets in the center plot have been updated by the regression. The resolution is visible improved from left to center. On the right the b-jet energies are updated once again with a kinematic fit which constrains the b-jet energies using the lepton resolution. Again there is a visible improvement in b-jet resolution inferred by the narrowing balance of the di-jet plus di-lepton system. |
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Additional Figure 11-a:
The figure above shows the ratio of the di-jet ${p_{\mathrm {T}}}$ to the di-lepton (V) ${p_{\mathrm {T}}}$ in the 2-lepton HF control region. The b-jets come directly from CMS reconstruction with charged hadron subtraction applied. |
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Additional Figure 11-b:
The figure above shows the ratio of the di-jet ${p_{\mathrm {T}}}$ to the di-lepton (V) ${p_{\mathrm {T}}}$ in the 2-lepton HF control region. The b-jets have been updated by the regression. The resolution is visible improved from left to center. |
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Additional Figure 11-c:
The figure above shows the ratio of the di-jet ${p_{\mathrm {T}}}$ to the di-lepton (V) ${p_{\mathrm {T}}}$ in the 2-lepton HF control region. The b-jet energies are updated once again with a kinematic fit which constrains the b-jet energies using the lepton resolution. Again there is a visible improvement in b-jet resolution inferred by the narrowing balance of the di-jet plus di-lepton system. |
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Additional Figure 12:
The three figures above highlight a few of the discriminating variables in control regions. The left plot is the azimuthal angle between the two candidate jets in the 0-lepton heavy flavor control region. The middle plot is the ${p_{\mathrm {T}}} $ of reconstructed W boson in the 1-lepton ttbar control region. The right plot is the number of tagged recoil jets used in the kinematic fit in the 2-lepton heavy flavor control region. |
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Additional Figure 12-a:
The figure above highlights a few of the discriminating variables in control regions. The plot is the azimuthal angle between the two candidate jets in the 0-lepton heavy flavor control region. |
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Additional Figure 12-b:
The figure above highlights a few of the discriminating variables in control regions. The plot is the ${p_{\mathrm {T}}} $ of reconstructed W boson in the 1-lepton ttbar control region. |
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Additional Figure 12-c:
The figure above highlights a few of the discriminating variables in control regions. The plot is the number of tagged recoil jets used in the kinematic fit in the 2-lepton heavy flavor control region. |
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Additional Figure 13:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The Z boson decays into two neutrinos which are inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 13-a:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The Z boson decays into two neutrinos which are inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 13-b:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The Z boson decays into two neutrinos which are inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 13-c:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The Z boson decays into two neutrinos which are inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 13-d:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The Z boson decays into two neutrinos which are inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 14:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one electron, which is shown in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 14-a:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one electron, which is shown in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 14-b:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one electron, which is shown in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 14-c:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one electron, which is shown in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 14-d:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one electron, which is shown in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 15:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one muon, which is shown going through muon chambers in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 15-a:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one muon, which is shown going through muon chambers in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 15-b:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one muon, which is shown going through muon chambers in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 15-c:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one muon, which is shown going through muon chambers in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 15-d:
An event candidate for the production of a W boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices (shown in lowers plots). The W boson decays into one muon, which is shown going through muon chambers in red, and a neutrino which is inferred from the large missing transverse momentum (shown in purple). |
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Additional Figure 16:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices. The Z boson decays into two muons, which are shown going through muon chambers in red. |
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Additional Figure 16-a:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices. The Z boson decays into two muons, which are shown going through muon chambers in red. |
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Additional Figure 16-b:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices. The Z boson decays into two muons, which are shown going through muon chambers in red. |
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Additional Figure 17:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices. These secondary vertices are shown in the zoomed figure. The Z boson decays into an electron and a positron (shown in red). |
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Additional Figure 17-a:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices. These secondary vertices are shown in the zoomed figure. The Z boson decays into an electron and a positron (shown in red). |
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Additional Figure 17-b:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices. These secondary vertices are shown in the zoomed figure. The Z boson decays into an electron and a positron (shown in red). |
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Additional Figure 17-c:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices. These secondary vertices are shown in the zoomed figure. The Z boson decays into an electron and a positron (shown in red). |
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Additional Figure 17-d:
An event candidate for the production of a Z boson in conjunction with a Higgs boson in CMS detector. The Higgs boson decays to two bottom quarks whose decays are characterized by jets (shown in blue) with secondary vertices which are separated by a few centimeters from the pp collision primary vertices. These secondary vertices are shown in the zoomed figure. The Z boson decays into an electron and a positron (shown in red). |
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Additional Figure 18:
The best-fit and uncertainty per-channel signal strengths extracted from a simultaneous fit of all channels for the 2017 analysis in the VZbb validation analysis. The per-channel signal strengths are compatible with the single signal strength fit with a probability of 64.2%. |
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Additional Figure 19:
Tagging jets from b-quarks is fundamental to this analysis. The distributions of the deepCSV b-tagging discriminator are shown for the less b-like jet of the two b-jet candidates in three different control regions. The left, center and right control regions are 0-lepton heavy flavor, 1-lepton ttbar and 2-lepton heavy flavor, respectively. |
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Additional Figure 19-a:
Tagging jets from b-quarks is fundamental to this analysis. The distributions of the deepCSV b-tagging discriminator are shown for the less b-like jet of the two b-jet candidates in 0-lepton heavy flavor control region. |
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Additional Figure 19-b:
Tagging jets from b-quarks is fundamental to this analysis. The distributions of the deepCSV b-tagging discriminator are shown for the less b-like jet of the two b-jet candidates in 1-lepton ttbar control region. |
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Additional Figure 19-c:
Tagging jets from b-quarks is fundamental to this analysis. The distributions of the deepCSV b-tagging discriminator are shown for the less b-like jet of the two b-jet candidates in 2-lepton heavy flavor control region. |
| Additional Tables | |
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Additional Table 1:
Higgs boson invariant mass resolution before (including regression) and after the kinematic fit in bins of ${{p_{\mathrm {T}}} ({\mathrm {V}})}$ and number of ISR jets. These estimates are made with Z bosons plus Higgs boson events where the Z boson decays to two charged leptons. This sample is simulated with POWHEG while showering is simulated with PYTHIA. The resolution listed in the table are the sigma in GeV of a Bukin function fit. |
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Additional Table 2:
Data/MC scale factors are needed per process to compensate for potential mis-modeling in the very specific phasespace of this analysis. Deviations from unity are not considered to have physical meaning. The 2017 fitted scale factors in the 0-, 1- and 2-lepton channels from SR+CRs fit are listed. The errors include both statistical and systematic uncertainties. Compatible fitted values are obtained from the CR-only fit. |
| References | ||||
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