CMS-PAS-HIG-16-033 | ||
Measurements of properties of the Higgs boson and search for an additional resonance in the four-lepton final state at $\sqrt{s} =$ 13 TeV | ||
CMS Collaboration | ||
August 2016 | ||
Abstract: Studies of Higgs boson properties are presented using the ${\rm H}\rightarrow{\rm Z}{\rm Z}\rightarrow4\ell$ ($\ell={\rm e},\mu$) decay channel. These studies are performed using a data sample corresponding to an integrated luminosity of 12.9 fb$^{-1}$ of pp collisions at a center-of-mass energy of 13 TeV collected by the CMS experiment at the LHC during 2016. The observed significance for the standard model Higgs boson with $m_{{\rm H}}=$ 125.09 GeV is 6.2$\sigma$, where the expected significance is 6.5$\sigma$. The signal strength modifier $\mu$, defined as the production cross section of the Higgs boson times its branching fraction to four leptons relative to the standard model expectation, is measured to be $\mu=$ 0.99$^{+0.33}_{-0.26}$ at $m_{\rm H}=$ 125.09 GeV. The signal-strength modifiers for the main Higgs boson production modes have also been constrained. The model independent fiducial cross section is measured to be 2.29$^{+0.74}_{-0.64}$ (stat) $^{+0.30}_{-0.23}$ (syst) $^{+0.01}_{-0.05}$ (model dep.) fb and differential cross sections as a function of the $p_{\rm T}$ of the Higgs boson and the number of associated jets are determined. The mass is measured to be $m_{{\rm H}}=$ 124.50$^{+0.48}_{-0.46}$ GeV and the width is constrained to be $\Gamma_{{\rm H}}< $ 41 MeV. The anomalous effects in the Higgs interactions with a pair of Z bosons are constrained under the assumption of a spin-zero resonance. Finally, a search for an additional resonance decaying to ZZ is performed for a range of masses up to 2.5 TeV and with various widths and no significant excess is observed. | ||
Links: CDS record (PDF) ; inSPIRE record ; CADI line (restricted) ; |
Figures & Tables | Summary | Additional Figures & Material | References | CMS Publications |
---|
Figures | |
png pdf |
Figure 1:
Signal relative purity of the six event categories in terms of the 5 main production mechanisms of the H(125) boson in a 118 $< {m_{4\ell }}<$ 130 GeV window. The $ { {\mathrm {W}} {\mathrm {H}} }$, $ { {\mathrm {Z}} {\mathrm {H}} }$ and $ { {\mathrm {t}}\bar{ \mathrm {t} } {\mathrm {H}} }$ processes are split according to the decay of associated objects, whereby X denotes anything else than a lepton. |
png pdf |
Figure 2:
Comparison between the observed data and MC prediction in the 2P2F (top left), 3P1F (top right), ${\rm 2P2L_{SS}}$ (bottom left) control regions. The MC prediction is not used in the analysis and is only shown for comparison. Bottom right: combination of the OS and SS method predictions for the reducible background in the signal region and the parametrized $m_{4\ell }$ shape. The yellow band shows the total uncertainty on the prediction. |
png pdf |
Figure 2-a:
Comparison between the observed data and MC prediction in the 2P2F control region. The MC prediction is not used in the analysis and is only shown for comparison. |
png pdf |
Figure 2-b:
Comparison between the observed data and MC prediction in the 3P1F control region. The MC prediction is not used in the analysis and is only shown for comparison. |
png pdf |
Figure 2-c:
Comparison between the observed data and MC prediction in the ${\rm 2P2L_{SS}}$ control region. The MC prediction is not used in the analysis and is only shown for comparison. |
png pdf |
Figure 2-d:
Combination of the OS and SS method predictions for the reducible background in the signal region and the parametrized $m_{4\ell }$ shape. The yellow band shows the total uncertainty on the prediction. |
png pdf |
Figure 3:
Distribution of the four-lepton reconstructed invariant mass $ {m_{4\ell }}$ in the full mass range (top) and the low-mass range (bottom left) and high-mass range (bottom right). Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. No events are observed with $ {m_{4\ell }}> $ 850 GeV. |
png pdf |
Figure 3-a:
Distribution of the four-lepton reconstructed invariant mass $ {m_{4\ell }}$ in the full mass range. Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. No events are observed with $ {m_{4\ell }}> $ 850 GeV. |
png pdf |
Figure 3-b:
Distribution of the four-lepton reconstructed invariant mass $ {m_{4\ell }}$ in the low-mass range. Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. No events are observed with $ {m_{4\ell }}> $ 850 GeV. |
png pdf |
Figure 3-c:
Distribution of the four-lepton reconstructed invariant mass $ {m_{4\ell }}$ in the high-mass range. Points with error bars represent the data and stacked histograms represent expected distributions. The ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. No events are observed with $ {m_{4\ell }}> $ 850 GeV. |
png pdf |
Figure 4:
Distribution of the $ {\mathrm {Z}}_1$ (left) and $ {\mathrm {Z}}_2$ (center) reconstructed invariant masses and correlation between the two (right) in the mass region 118 $< {m_{4\ell }}< $ 130 GeV. The stacked histograms and the gray scale represent expected distributions, and points represent the data. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. |
png pdf |
Figure 4-a:
Distribution of the $ {\mathrm {Z}}_1$ reconstructed invariant mass in the mass region 118 $< {m_{4\ell }}< $ 130 GeV. The stacked histograms represent expected distributions, and points represent the data. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. |
png pdf |
Figure 4-b:
Distribution of the $ {\mathrm {Z}}_2$ reconstructed invariant mass in the mass region 118 $< {m_{4\ell }}< $ 130 GeV. The stacked histograms represent expected distributions, and points represent the data. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. |
png pdf |
Figure 4-c:
Correlation between the $ {\mathrm {Z}}_1$ and $ {\mathrm {Z}}_2$ reconstructed invariant masses in the mass region 118 $< {m_{4\ell }}< $ 130 GeV. The gray scale represents expected distributions, and points represent the data. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. |
png pdf |
Figure 5:
Left: Distribution of the kinematic discriminant $ {{\cal D}^{\rm kin}_{\rm bkg}} $ in the mass region 118 $< {m_{4\ell }}< $ 130 GeV. Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. Right: Distribution of $ {{\cal D}^{\rm kin}_{\rm bkg}} $ versus $ {m_{4\ell }}$ in the mass region 100 $ < {m_{4\ell }}< $ 170 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $ {m_{ {\mathrm {H}} }}=$ 125 GeV. The points show the data and the horizontal bars represent the measured event-by-event mass uncertainties. Different marker styles are used to denote the categorization of the events. |
png pdf |
Figure 5-a:
Distribution of the kinematic discriminant $ {{\cal D}^{\rm kin}_{\rm bkg}} $ in the mass region 118 $< {m_{4\ell }}< $ 130 GeV. Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. |
png pdf |
Figure 5-b:
Distribution of $ {{\cal D}^{\rm kin}_{\rm bkg}} $ versus $ {m_{4\ell }}$ in the mass region 100 $ < {m_{4\ell }}< $ 170 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $ {m_{ {\mathrm {H}} }}=$ 125 GeV. The points show the data and the horizontal bars represent the measured event-by-event mass uncertainties. Different marker styles are used to denote the categorization of the events. |
png pdf |
Figure 6:
Distribution of categorization discriminants in the mass region 118 $ < {m_{4\ell }} < $ 130 GeV. Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. The vertical gray dashed lines denote the working points used in the event categorization. |
png pdf |
Figure 6-a:
Distribution of categorization discriminant $ {{\cal D}_{\text{2jet}}} $ in the mass region 118 $ < {m_{4\ell }} < $ 130 GeV. Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. The vertical gray dashed line denotes the working points used in the event categorization. |
png pdf |
Figure 6-b:
Distribution of categorization discriminant $ {{\cal D}_{\text{2jet}}} $ in the mass region 118 $ < {m_{4\ell }} < $ 130 GeV. Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. The vertical gray dashed line denotes the working points used in the event categorization. |
png pdf |
Figure 6-c:
Distribution of categorization discriminant $ {{\cal D}_{\mathrm{WH}}} $ in the mass region 118 $ < {m_{4\ell }} < $ 130 GeV. Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. The vertical gray dashed line denotes the working points used in the event categorization. |
png pdf |
Figure 6-d:
Distribution of categorization discriminant $ {{\cal D}_{\mathrm{ZH}}} $ in the mass region 118 $ < {m_{4\ell }} < $ 130 GeV. Points with error bars represent the data and stacked histograms represent expected distributions. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation, the Z+X background to the estimation from data. The vertical gray dashed line denotes the working points used in the event categorization. |
png pdf |
Figure 7:
Left: Significance of the local fluctuation with respect to the SM expectation as a function of the Higgs boson mass. Dashed lines show the mean expected significance of the SM Higgs boson for a given mass hypothesis. Right: Observed values of the signal strength $\mu =\sigma /\sigma _{SM}$ for the six event categories, compared to the combined $\mu $ shown as a vertical line. The horizontal bars and the filled band indicate the $\pm $1$\sigma $ uncertainties. The uncertainties include both statistical and systematic sources. |
png pdf |
Figure 7-a:
Significance of the local fluctuation with respect to the SM expectation as a function of the Higgs boson mass. Dashed lines show the mean expected significance of the SM Higgs boson for a given mass hypothesis. |
png pdf |
Figure 7-b:
Observed values of the signal strength $\mu =\sigma /\sigma _{SM}$ for the six event categories, compared to the combined $\mu $ shown as a vertical line. The horizontal bars and the filled band indicate the $\pm $1$\sigma $ uncertainties. The uncertainties include both statistical and systematic sources. |
png pdf |
Figure 8:
Left: Result of the 2D likelihood scan for the $ {\mu _{ {\mathrm {g}} {\mathrm {g}} {\mathrm {H}} , {\mathrm {t}\overline {\mathrm {t}}} {\mathrm {H}} }} $ and $ {\mu _{\mathrm {VBF},\mathrm {V {\mathrm {H}} }}} $ signal-strength modifiers. The solid and dashed contours show the 68% and 95% CL regions, respectively. The cross indicates the best-fit values, and the diamond represents the expected values for the SM Higgs boson. Right: Results of likelihood scans for the signal strength modifiers corresponding to the five main Higgs boson production modes, compared to the combined $\mu $ shown as a vertical line. The horizontal bars and the filled band indicate the $\pm $1$\sigma $ uncertainties. The uncertainties include both statistical and systematic sources. |
png pdf |
Figure 8-a:
Result of the 2D likelihood scan for the $ {\mu _{ {\mathrm {g}} {\mathrm {g}} {\mathrm {H}} , {\mathrm {t}\overline {\mathrm {t}}} {\mathrm {H}} }} $ and $ {\mu _{\mathrm {VBF},\mathrm {V {\mathrm {H}} }}} $ signal-strength modifiers. The solid and dashed contours show the 68% and 95% CL regions, respectively. The cross indicates the best-fit values, and the diamond represents the expected values for the SM Higgs boson. |
png pdf |
Figure 8-b:
Results of likelihood scans for the signal strength modifiers corresponding to the five main Higgs boson production modes, compared to the combined $\mu $ shown as a vertical line. The horizontal bars and the filled band indicate the $\pm $1$\sigma $ uncertainties. The uncertainties include both statistical and systematic sources. |
png pdf |
Figure 9:
Left: The measured fiducial cross section as a function of $\sqrt {s}$. The acceptance is calculated using POWHEG at $\sqrt {s}=$ 13 TeV and HRes [50,52] at $\sqrt {s} =$ 7 and 8 TeV and the theoretical uncertainty on the gluon fusion contribution is taken from Ref. [25]. The model dependence uses experimental constraints on the relative fraction of the various production modes, as described in the text, and is much less than 1% for the $\sqrt {s} =$ 7 and 8 TeV measurements. Right: measured fiducial cross section in each final state. The sub-dominant component of the the signal (VBF $+$ VH $+ { {\mathrm {t}}\bar{ \mathrm {t} } {\mathrm {H}} }$) is denoted as XH. |
png pdf |
Figure 9-a:
The measured fiducial cross section as a function of $\sqrt {s}$. The acceptance is calculated using POWHEG at $\sqrt {s}=$ 13 TeV and HRes [50,52] at $\sqrt {s} =$ 7 and 8 TeV and the theoretical uncertainty on the gluon fusion contribution is taken from Ref. [25]. The model dependence uses experimental constraints on the relative fraction of the various production modes, as described in the text, and is much less than 1% for the $\sqrt {s} =$ 7 and 8 TeV measurements. |
png pdf |
Figure 9-b:
Measured fiducial cross section in each final state. The sub-dominant component of the the signal (VBF $+$ VH $+ { {\mathrm {t}}\bar{ \mathrm {t} } {\mathrm {H}} }$) is denoted as XH. |
png pdf |
Figure 10:
Result of the differential cross section measurement for $ {p_{\mathrm {T}}} ({\rm H})$ (left) and $N(\text{jets})$ (right). The acceptance and theoretical uncertainties in the differential bins are are calculated using POWHEG. |
png pdf |
Figure 10-a:
Result of the differential cross section measurement for $ {p_{\mathrm {T}}} ({\rm H})$. The acceptance and theoretical uncertainties in the differential bins are are calculated using POWHEG. |
png pdf |
Figure 10-b:
Result of the differential cross section measurement for $N(\text{jets})$. The acceptance and theoretical uncertainties in the differential bins are are calculated using POWHEG. |
png pdf |
Figure 11:
left: 1D likelihood scan as a function of mass for the 1D, 2D, and 3D measurement. right: 1D likelihood scan as a function of mass for the different final states and the combination of all final states for the 3D measurement. Solid lines represents the scan with full uncertainties included, dashed lines statistical error only. |
png pdf |
Figure 11-a:
1D likelihood scan as a function of mass for the 1D, 2D, and 3D measurement. Solid lines represents the scan with full uncertainties included, dashed lines statistical error only. |
png pdf |
Figure 11-b:
1D likelihood scan as a function of mass for the different final states and the combination of all final states for the 3D measurement. Solid lines represents the scan with full uncertainties included, dashed lines statistical error only. |
png pdf |
Figure 12:
Observed likelihood scan of $m_{\mathrm{H}}$ and $\Gamma _{\mathrm{H}}$ using the full mass range 100 $ < m_{4\ell } < $ 1600 GeV between 0 $ < \Gamma _{\mathrm{H}} < $ 100 MeV and the signal range 105 $ < m_{4\ell } < $ 140 GeV between 0 $ < \Gamma _{\mathrm{H}} < $ 5 GeV with 12.9 fb$^{-1}$ data. |
png pdf |
Figure 12-a:
Observed likelihood scan of $m_{\mathrm{H}}$ and $\Gamma _{\mathrm{H}}$ using the full mass range 100 $ < m_{4\ell } < $ 1600 GeV between 0 $ < \Gamma _{\mathrm{H}} < $ 100 MeV with 12.9 fb$^{-1}$ data. |
png pdf |
Figure 12-b:
Observed likelihood scan of $m_{\mathrm{H}}$ and $\Gamma _{\mathrm{H}}$ using the signal range 105 $ < m_{4\ell } < $ 140 GeV between 0 $ < \Gamma _{\mathrm{H}} < $ 5 GeV with 12.9 fb$^{-1}$ data. |
png pdf |
Figure 13:
Observed and expected likelihood scan of $\Gamma _{\mathrm{H}}$ using the full mass range 100 $ < m_{4\ell } < $ 1600 GeV (left) or on-shell only range 105 $ < m_{4\ell } < $ 140 GeV (right) with 12.9 fb$^{-1}$ data, with $m_{\mathrm{H}}$ floated. |
png pdf |
Figure 13-a:
Observed and expected likelihood scan of $\Gamma _{\mathrm{H}}$ using the full mass range 100 $ < m_{4\ell } < $ 1600 GeV with 12.9 fb$^{-1}$ data, with $m_{\mathrm{H}}$ floated. |
png pdf |
Figure 13-b:
Observed and expected likelihood scan of $\Gamma _{\mathrm{H}}$ using the on-shell only range 105 $ < m_{4\ell } < $ 140 GeV with 12.9 fb$^{-1}$ data, with $m_{\mathrm{H}}$ floated. |
png pdf |
Figure 14:
Distributions of events (data points) and expectations (histograms) in the following kinematic discriminants: $\mathcal {D}_\text {bkg}$ (top left), $\mathcal {D}_{0-}$ (top right), $\mathcal {D}_{CP}$ (middle left), $\mathcal {D}_\text {int}$ (middle right), $\mathcal {D}_{0h+}$ (bottom left), $\mathcal {D}_{\Lambda 1}$ (bottom right). |
png pdf |
Figure 14-a:
Distributions of events (data points) and expectations (histograms) in the kinematic discriminant $\mathcal {D}_\text {bkg}$. |
png pdf |
Figure 14-b:
Distributions of events (data points) and expectations (histograms) in the kinematic discriminant $\mathcal {D}_{0-}$. |
png pdf |
Figure 14-c:
Distributions of events (data points) and expectations (histograms) in the kinematic discriminant $\mathcal {D}_{CP}$. |
png pdf |
Figure 14-d:
Distributions of events (data points) and expectations (histograms) in the kinematic discriminant $\mathcal {D}_\text {int}$. |
png pdf |
Figure 14-e:
Distributions of events (data points) and expectations (histograms) in the kinematic discriminant $\mathcal {D}_{0h+}$. |
png pdf |
Figure 14-f:
Distributions of events (data points) and expectations (histograms) in the kinematic discriminant $\mathcal {D}_{\Lambda 1}$. |
png pdf |
Figure 15:
Observed and expected likelihood scan of the $f_{a3}\cos(\phi _{a3})$ (top), $f_{a2}\cos(\phi _{a2})$ (middle), $f_{\Lambda 1}\cos(\phi _{\Lambda 1})$ (bottom) parameters with 15.7 fb$^{-1}$ of data at 13 TeV. It is assumed that ratios of anomalous couplings are real and therefore $\cos(\phi _{ai})= \pm$1. |
png pdf |
Figure 15-a:
Observed and expected likelihood scan of the $f_{a3}\cos(\phi _{a3})$ parameter with 15.7 fb$^{-1}$ of data at 13 TeV. It is assumed that ratios of anomalous couplings are real and therefore $\cos(\phi _{ai})= \pm$1. |
png pdf |
Figure 15-b:
Observed and expected likelihood scan of the $f_{a2}\cos(\phi _{a2})$ parameter with 15.7 fb$^{-1}$ of data at 13 TeV. It is assumed that ratios of anomalous couplings are real and therefore $\cos(\phi _{ai})= \pm$1. |
png pdf |
Figure 15-c:
Observed and expected likelihood scan of the $f_{\Lambda 1}\cos(\phi _{\Lambda 1})$ parameter with 15.7 fb$^{-1}$ of data at 13 TeV. It is assumed that ratios of anomalous couplings are real and therefore $\cos(\phi _{ai})= \pm$1. |
png pdf |
Figure 16:
Top: Observed and expected upper limits at the 95% CL on the $\mathrm{X}\to ZZ \to 4\ell $ cross section $\sigma _\mathrm{X}$ (including four-lepton branching fraction) as a function of $m_\mathrm{X}$ at several $\Gamma _\mathrm{X}$ values with $f_{\rm VBF}$ floated, with 12.9 fb$^{-1}$ of data at 13 TeV. Bottom: Same as above but with $f_{\rm VBF}=1$ fixed. |
png pdf |
Figure 16-a:
Observed and expected upper limits at the 95% CL on the $\mathrm{X}\to ZZ \to 4\ell $ cross section $\sigma _\mathrm{X}$ (including four-lepton branching fraction) as a function of $m_\mathrm{X}$ at several $\Gamma _\mathrm{X}$ values with $f_{\rm VBF}$ floated, with 12.9 fb$^{-1}$ of data at 13 TeV. |
png pdf |
Figure 16-b:
Observed and expected upper limits at the 95% CL on the $\mathrm{X}\to ZZ \to 4\ell $ cross section $\sigma _\mathrm{X}$ (including four-lepton branching fraction) as a function of $m_\mathrm{X}$ at several $\Gamma _\mathrm{X}$ values with $f_{\rm VBF}=1$ fixed, with 12.9 fb$^{-1}$ of data at 13 TeV. |
Tables | |
png pdf |
Table 1:
List of observables $\vec{x}$ used in the analysis of the HVV anomalous couplings. The $\mathcal {D}_{0h+}$ discriminant is included in the $f_{\Lambda 1}$ measurement in order to allow a joint fit with $f_{a2}$. For more details, see Ref. [15]. |
png pdf |
Table 2:
The number of observed candidate events compared to the mean expected background and signal rates for each final state, for the full mass range $ {m_{4\ell }}>$ 70 GeV. Uncertainties include statistical and systematic sources. |
png pdf |
Table 3:
The number of observed candidate events compared to the mean expected background and signal rates for each final state, for the mass range 118 $< {m_{4\ell }}<$ 130 GeV. Uncertainties include statistical and systematic sources. |
png pdf |
Table 4:
The number of observed candidate events compared to the mean expected background and signal rates for each event category, for the mass range 118 $ < {m_{4\ell }}<$ 130 GeV. |
png pdf |
Table 5:
Summary of the systematic uncertainties in the $ { {\mathrm {H}} \to 4\ell }$ measurements. |
png pdf |
Table 6:
Summary of requirements and selections used in the definition of the fiducial phase space for the $ { {\mathrm {H}} \to 4\ell }$ cross section measurements. |
png pdf |
Table 7:
Summary of different Standard Model signal models. For all production modes the values given are for $m_{\rm H}=$ 125 GeV. The uncertainties listed are statistical uncertainties only, and the statistical uncertainty on the acceptance is $\sim$0.001. |
png pdf |
Table 8:
Best fit values for the mass of the new boson measured in the $4\ell $, $\ell = {\mathrm {e}}, {{\mu }}$ final states, with 1D, 2D and 3D fit, respectively, as described in the text along with the uncertainty. For the 1D and 2D we give the total uncertainty only, while for the nominal 3D fit we separate the contribution from statistical and systematic uncertainty. |
png pdf |
Table 9:
Summary of allowed 68%CL (central values with uncertainties) and 95%CL (ranges in square brackets) intervals on the width $\Gamma _{\mathrm{H}}$ of the ${\rm H}(125)$ boson. The expected results are quoted for the SM signal production cross section ($\mu _{\rm VBF+VH}=\mu _{\rm ggH+mathrm{ t \bar{t} }H}=1$) and the values of $m_{\mathrm{H}}=$ 125 GeV and $\Gamma _{\mathrm{H}}=$ 0.0041 GeV. |
png pdf |
Table 10:
Summary of allowed 68%CL (central values with uncertainties) and 95%CL (ranges in square brackets) intervals on anomalous coupling parameters in HZZ interactions under the assumption that all the coupling ratios are real ($\phi _{ai}=$ 0 or $\pi $). The $f_{\Lambda 1}\cos(\phi _{\Lambda 1})$ observed 68%CL interval allows values below $-1$ in order to include the range $ [0.91,1.00]$. The expected results are quoted for the SM signal production cross section ($\mu =$ 1). |
Summary |
Several studies of Higgs boson production in the four-lepton final state at $ \sqrt{s} = $ 13 TeV have been presented, using data samples corresponding to an integrated luminosity of 12.9 fb$^{-1}$. The observed significance for the SM Higgs boson at a mass of $m_{\mathrm{ H }}=$ 125.09 GeV is 6.2$\sigma$, where the expected significance is 6.5$\sigma$. The measured signal strength is $\mu =$ 0.99$^{+0.33}_{-0.26} $, and the measured signal strength modifiers associated with fermions and vector bosons are ${\mu_{\mathrm{gg}\mathrm{ H },\,\mathrm{ t \bar{t} }\mathrm{ H }}} =$ 1.00$^{+0.39}_{-0.32}$ and ${\mu_{\mathrm{VBF},\mathrm{V\mathrm{ H }}}} =$ 0.91$^{+1.56}_{-0.91}$, respectively. The model-independent fiducial cross section at $ \sqrt{s} = $ 13 TeV for this boson is measured to be 2.29$^{+0.74}_{-0.64}$ (stat)$^{+0.30}_{-0.23}$ (syst)$^{+0.01}_{-0.05}$ (model dep.) fb. The mass is measured to be $m_{{\rm H}}=$ 124.50$^{+0.48}_{-0.46} $ GeV and the width is constrained to be $\Gamma_{{\rm H}}<$ 41 MeV. Constraints on spin-zero anomalous couplings are set. All results are consistent, within their uncertainties, with the expectations for the SM Higgs boson. In addition, upper limits at a 95% CL are set on the production of an additional Higgs boson for masses up to 2.5 TeV and for various widths. The details of the exclusions depend on the assumptions of width and production, but in general no significant excesses appear under any of the scenarios considered. |
Additional Figures | |
png pdf |
Additional Figure 1:
Distribution of the $\mathrm{ Z } _1$ (left) and $\mathrm{ Z } _2$ (middle) reconstructed invariant masses in the region $m_{4\ell } > $ 70 GeV. The stacked histograms represent expected distributions, and points represent the data. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation and the Z+X background to the estimation from data. Right: Correlation between the reconstructed invariant masses $\mathrm{ Z } _1$ and $\mathrm{ Z } _2$ in the region $m_{4\ell }> $ 70 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $m_{\rm H}=$ 125 GeV. |
png pdf |
Additional Figure 1-a:
Distribution of the $\mathrm{ Z } _1$ reconstructed invariant mass in the region $m_{4\ell } > $ 70 GeV. The stacked histograms represent expected distributions, and points represent the data. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation and the Z+X background to the estimation from data. |
png pdf |
Additional Figure 1-b:
Distribution of the $\mathrm{ Z } _2$ reconstructed invariant mass in the region $m_{4\ell } > $ 70 GeV. The stacked histograms represent expected distributions, and points represent the data. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation and the Z+X background to the estimation from data. |
png pdf |
Additional Figure 1-c:
Correlation between the reconstructed invariant masses $\mathrm{ Z } _1$ and $\mathrm{ Z } _2$ in the region $m_{4\ell }> $ 70 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $m_{\rm H}=$ 125 GeV. |
png pdf |
Additional Figure 2:
Left: Distribution of ${\cal D}^{\rm kin}_{\rm bkg}$ in the region $m_{4\ell }> $ 70 GeV. The stacked histograms represent the expected distributions, and points represent the data. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation and the Z+X background to the estimation from data. Right: 2D distribution of ${\cal D}^{\rm kin}_{\rm bkg}$ vs $m_{4\ell }$ in the region 170 $ < m_{4\ell } < $ 850 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $m_{\rm H}=$ 125 GeV. The points show the data and the horizontal bars represent the measured event-by-event mass uncertainties. |
png pdf |
Additional Figure 2-a:
Distribution of ${\cal D}^{\rm kin}_{\rm bkg}$ in the region $m_{4\ell }> $ 70 GeV. The stacked histograms represent the expected distributions, and points represent the data. The 125 GeV Higgs boson signal and the ZZ backgrounds are normalized to the SM expectation and the Z+X background to the estimation from data. |
png pdf |
Additional Figure 2-b:
2D distribution of ${\cal D}^{\rm kin}_{\rm bkg}$ vs $m_{4\ell }$ in the region 170 $ < m_{4\ell } < $ 850 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $m_{\rm H}=$ 125 GeV. The points show the data and the horizontal bars represent the measured event-by-event mass uncertainties. |
png pdf |
Additional Figure 3:
2D distributions of ${\mathcal D}_{\rm 1jet}$ (top left), ${\mathcal D}_{\rm 2jet}$ (top right), ${\mathcal D}_{\rm WH}$ (bottom left) and ${\mathcal D}_{\rm ZH}$ (bottom right) vs $m_{4\ell }$ in the region 100 $ < m_{4\ell } < $ 170 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $m_{\rm H}=$ 125 GeV. The points show the data and the horizontal bars represent the measured event-by-event mass uncertainties. The gray dashed lines denote the working points used in the event categorization and different marker styles are used to denote the final categorization of the events. |
png pdf |
Additional Figure 3-a:
2D distribution of ${\mathcal D}_{\rm 1jet}$ vs $m_{4\ell }$ in the region 100 $ < m_{4\ell } < $ 170 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $m_{\rm H}=$ 125 GeV. The points show the data and the horizontal bars represent the measured event-by-event mass uncertainties. The gray dashed lines denote the working points used in the event categorization and different marker styles are used to denote the final categorization of the events. |
png pdf |
Additional Figure 3-b:
2D distribution of ${\mathcal D}_{\rm 2jet}$ vs $m_{4\ell }$ in the region 100 $ < m_{4\ell } < $ 170 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $m_{\rm H}=$ 125 GeV. The points show the data and the horizontal bars represent the measured event-by-event mass uncertainties. The gray dashed lines denote the working points used in the event categorization and different marker styles are used to denote the final categorization of the events. |
png pdf |
Additional Figure 3-c:
2D distribution of ${\mathcal D}_{\rm WH}$ vs $m_{4\ell }$ in the region 100 $ < m_{4\ell } < $ 170 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $m_{\rm H}=$ 125 GeV. The points show the data and the horizontal bars represent the measured event-by-event mass uncertainties. The gray dashed lines denote the working points used in the event categorization and different marker styles are used to denote the final categorization of the events. |
png pdf |
Additional Figure 3-d:
2D distribution of ${\mathcal D}_{\rm ZH}$ vs $m_{4\ell }$ in the region 100 $ < m_{4\ell } < $ 170 GeV. The gray scale represents the expected relative density of ZZ background plus Higgs boson signal for $m_{\rm H}=$ 125 GeV. The points show the data and the horizontal bars represent the measured event-by-event mass uncertainties. The gray dashed lines denote the working points used in the event categorization and different marker styles are used to denote the final categorization of the events. |
png pdf |
Additional Figure 4:
Significance of the local fluctuation with respect to the SM expectation as a function of the Higgs boson mass using the 1D (gray) and 2D (black) likelihood. Dashed lines show the mean expected significance of the SM Higgs boson for a given mass hypothesis and solid lines show the observed significance. |
png pdf |
Additional Figure 5:
Comparison of measured mass resolution with the predicted dilepton mass resolution using the event-by-event mass uncertainty for $\mathrm{ Z } \to \ell \ell $ events in data. The dashed lines denote a $\pm$20% region, used as the systematic uncertainty on the resolution. |
png pdf |
Additional Figure 6:
Distribution of $m_{4\ell }$ for events in the reduced selection electron category used in the search for a high mass resonance. The ZZ backgrounds are normalized to the SM expectation and the Z+X background to the estimation from data. |
Additional Material |
Higgs and associated vector boson event recorded by CMS (Run 2, 13 TeV) The following figures display a real proton-proton collision event at 13 TeV in the CMS detector in which two high-energy electrons (green lines), two high-energy muons (red lines), and two high-energy jets (dark yellow cones) are observed. The event shows characteristics expected in the production of a Higgs boson in association with a vector boson with the decay of the Higgs boson in four leptons and the decay of the vector boson in two jets, and is also consistent with background standard model physics processes. Photograph: Mc Cauley, Thomas Link to CDS record: CMS-PHO-EVENTS-2016-006. |
|||
png |
png |
png |
png |
Higgs boson produced via vector boson fusion event recorded by CMS (Run 2, 13 TeV) The following figures display a real proton-proton collision event at 13 TeV in the CMS detector in which two high-energy electrons (green lines), two high-energy muons (red lines), and two-high energy jets (dark yellow cones) are observed. The event shows characteristics expected from Higgs boson production via vector boson fusion with subsequent decay of the Higgs boson in four leptons, and is also consistent with background standard model physics processes. Photograph: Mc Cauley, Thomas Link to CDS record: CMS-PHO-EVENTS-2016-007. |
||
png |
png |
png |
References | ||||
1 | CMS Collaboration | Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC | PLB 716 (2012) 30 | CMS-HIG-12-028 1207.7235 |
2 | ATLAS Collaboration | Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC | PLB 716 (2012) 1 | 1207.7214 |
3 | F. Englert and R. Brout | Broken Symmetry and the Mass of Gauge Vector Mesons | PRL 13 (1964) 321 | |
4 | P. W. Higgs | Broken symmetries, massless particles and gauge fields | PL12 (1964) 132 | |
5 | P. W. Higgs | Broken Symmetries and the Masses of Gauge Bosons | PRL 13 (1964) 508 | |
6 | G. Guralnik, C. Hagen, and T. Kibble | Global Conservation Laws and Massless Particles | PRL 13 (1964) 585 | |
7 | P. W. Higgs | Spontaneous Symmetry Breakdown without Massless Bosons | PR145 (1966) 1156 | |
8 | T. Kibble | Symmetry breaking in nonAbelian gauge theories | PR155 (1967) 1554 | |
9 | CMS Collaboration | Precise determination of the mass of the Higgs boson and tests of compatibility of its couplings with the standard model predictions using proton collisions at 7 and 8 $ \,\text {TeV} $ | EPJC 75 (2015) 212 | CMS-HIG-14-009 1412.8662 |
10 | ATLAS Collaboration | Measurements of the Higgs boson production and decay rates and coupling strengths using $ pp $ collision data at $ \sqrt{s}=7 $ and 8 TeV in the ATLAS experiment | EPJC 76 (2016) | 1507.04548 |
11 | ATLAS, CMS Collaboration | Combined Measurement of the Higgs Boson Mass in $ pp $ Collisions at $ \sqrt{s}=7 $ and 8 TeV with the ATLAS and CMS Experiments | PRL 114 (2015) 191803 | 1503.07589 |
12 | ATLAS and CMS Collaborations | Measurements of the Higgs boson production and decay rates and constraints on its couplings from a combined ATLAS and CMS analysis of the LHC pp collision data at $ \sqrt{s}=7 $ and 8 TeV | CDS | CMS-HIG-15-002 1606.02266 |
13 | CMS Collaboration | Measurement of the properties of a Higgs boson in the four-lepton final state | PRD 89 (2014) 092007 | CMS-HIG-13-002 1312.5353 |
14 | CMS Collaboration | Study of the Mass and Spin-Parity of the Higgs Boson Candidate via Its Decays to $ Z $ Boson Pairs | PRL 110 (2013) 081803 | CMS-HIG-12-041 1212.6639 |
15 | CMS Collaboration | Constraints on the spin-parity and anomalous HVV couplings of the Higgs boson in proton collisions at 7 and 8$ TeV $ | PRD 92 (2015) 012004 | CMS-HIG-14-018 1411.3441 |
16 | CMS Collaboration | Constraints on the Higgs boson width from off-shell production and decay to $ \mathrm{ Z } $-boson pairs | PLB 736 (2014) 64 | CMS-HIG-14-002 1405.3455 |
17 | CMS Collaboration | Limits on the Higgs boson lifetime and width from its decay to four charged leptons | PRD 92 (2015) 072010 | CMS-HIG-14-036 1507.06656 |
18 | CMS Collaboration | Measurement of differential and integrated fiducial cross sections for Higgs boson production in the four-lepton decay channel in pp collisions at $ \sqrt{s}=7 $ and 8 TeV | JHEP 04 (2016) 005 | CMS-HIG-14-028 1512.08377 |
19 | CMS Collaboration | Studies of Higgs boson production in the four-lepton final state at $ \sqrt{s} $ = 13 TeV | CMS-PAS-HIG-15-004 | |
20 | CMS Collaboration | The CMS experiment at the CERN LHC | JINST 3 (2008) S08004 | CMS-00-001 |
21 | S. Alioli, P. Nason, C. Oleari, and E. Re | NLO vector-boson production matched with shower in POWHEG | JHEP 07 (2008) 060 | 0805.4802 |
22 | P. Nason | A new method for combining NLO QCD with shower Monte Carlo algorithms | JHEP 11 (2004) 040 | hep-ph/0409146 |
23 | S. Frixione, P. Nason, and C. Oleari | Matching NLO QCD computations with parton shower simulations: the POWHEG method | JHEP 11 (2007) 070 | 0709.2092 |
24 | G. Luisoni, P. Nason, C. Oleari, and F. Tramontano | HW$ ^{\pm} $/HZ + 0 and 1 jet at NLO with the POWHEG BOX interfaced to GoSam and their merging within MiNLO | JHEP 10 (2013) 1 | 1306.2542 |
25 | C. Anastasiou et al. | High precision determination of the gluon fusion Higgs boson cross-section at the LHC | JHEP 2016 (2016), no. 5, 1 | 1602.00695 |
26 | R. Ball et al. | Unbiased global determination of parton distributions and their uncertainties at NNLO and at LO | Nucl. Phys. B 855 (2012), no. 2, 153 | 1107.2652 |
27 | Y. Gao et al. | Spin determination of single-produced resonances at hadron colliders | PRD 81 (2010) 075022, , [Erratum: \DOI10.1103/PhysRevD.81.079905] | 1001.3396 |
28 | S. Bolognesi et al. | On the spin and parity of a single-produced resonance at the LHC | PRD 86 (2012) 095031 | 1208.4018 |
29 | J. M. Campbell and R. K. Ellis | MCFM for the Tevatron and the LHC | NPPS 205 (2010) 10 | 1007.3492 |
30 | T. Sjj\"ostrand et al. | An introduction to PYTHIA 8.2 | Computer Physics Communications 191 (2015) 159 | |
31 | GEANT4 Collaboration | GEANT4: a simulation toolkit | NIMA 506 (2003) 250 | |
32 | J. Allison et al. | Geant4 developments and applications | IEEE Trans. Nucl. Sci. 53 (2006) 270 | |
33 | CMS Collaboration | Particle-flow event reconstruction in CMS and performance for jets, taus, and $ E_{\mathrm{T}}^{\text{miss}} $ | CDS | |
34 | CMS Collaboration | Commissioning of the particle-flow event with the first LHC collisions recorded in the CMS detector | CDS | |
35 | CMS Collaboration | Performance of electron reconstruction and selection with the CMS detector in proton-proton collisions at $ \sqrt{s} = 8 $$ TeV $ | JINST 10 (2015) P06005 | CMS-EGM-13-001 1502.02701 |
36 | CMS Collaboration | Performance of CMS muon reconstruction in $ pp $ collision events at $ \sqrt{s} = 7 $$ TeV $ | JINST 7 (2012) P10002 | CMS-MUO-10-004 1206.4071 |
37 | CMS Collaboration | W-like measurement of the Z boson mass using dimuon events collected in pp collisions at $ \sqrt{s}= $ 7 TeV | CMS-PAS-SMP-14-007 | |
38 | M. Cacciari, G. P. Salam, and G. Soyez | The anti-$ k_t $ jet clustering algorithm | JHEP 04 (2008) 063 | 0802.1189 |
39 | M. Cacciari, G. P. Salam, and G. Soyez | FastJet user manual | EPJC 72 (2012) 1896 | 1111.6097 |
40 | CMS Collaboration | Determination of jet energy calibration and transverse momentum resolution in CMS | JINST 6 (2011) P11002 | CMS-JME-10-011 1107.4277 |
41 | I. Anderson et al. | Constraining anomalous $ HVV $ interactions at proton and lepton colliders | PRD 89 (2014) 035007 | 1309.4819 |
42 | CMS Collaboration | Search for a Higgs Boson in the Mass Range from 145 to 1000 GeV Decaying to a Pair of W or Z Bosons | JHEP 10 (2015) 144 | CMS-HIG-13-031 1504.00936 |
43 | M. Grazzini, S. Kallweit, and D. Rathlev | ZZ production at the LHC: Fiducial cross sections and distributions in NNLO QCD | PLB 750 (2015) 407 -- 410 | 1507.06257 |
44 | M. Bonvini et al. | Signal-background interference effects in $ gg \to H \to WW $ beyond leading order | PRD 88 (2013) 034032 | 1304.3053 |
45 | K. Melnikov and M. Dowling | Production of two Z-bosons in gluon fusion in the heavy top quark approximation | PLB 744 (2015) 43 | 1503.01274 |
46 | C. S. Li, H. T. Li, D. Y. Shao, and J. Wang | Soft gluon resummation in the signal-background interference process of $ gg(\to h^*) \to ZZ $~ | 1504.02388 | |
47 | G. Passarino | Higgs CAT | EPJC 74 (2014) 2866 | 1312.2397 |
48 | S. Catani and M. Grazzini | An NNLO subtraction formalism in hadron collisions and its application to Higgs boson production at the LHC | PRL 98 (2007) 222002 | hep-ph/0703012 |
49 | M. Grazzini | NNLO predictions for the Higgs boson signal in the H $ \to $ WW $ \to\ell\nu\ell\nu $ and H$ \to $ ZZ $ \to4\ell $ decay channels | JHEP 02 (2008) 043 | 0801.3232 |
50 | M. Grazzini and H. Sargsyan | Heavy-quark mass effects in Higgs boson production at the LHC | JHEP 09 (2013) 129 | 1306.4581 |
51 | L. Landau | On the energy loss of fast particles by ionization | J. Phys. (USSR) 8 (1944)201 | |
52 | D. de Florian, G. Ferrera, M. Grazzini, and D. Tommasini | Higgs boson production at the LHC: transverse momentum resummation effects in the $ H \to \gamma \gamma $, $ H \to WW \to \ell\nu\ell\nu $ and $ H \to ZZ \to 4\ell $ decay modes | JHEP 06 (2012) 132 | 1203.6321 |
53 | CMS Collaboration | Search for a Higgs Boson in the Mass Range from 145 to 1000 GeV Decaying to a Pair of W or Z Bosons | JHEP 10 (2015) 144 | CMS-HIG-13-031 1504.00936 |
54 | R. D. Cousins | Why isn't every physicist a Bayesian? | Am. J. Phys. 63 (1995) 398 | |
55 | ATLAS and CMS Collaborations, LHC Higgs Combination Group | Procedure for the LHC Higgs boson search combination in Summer 2011 | ATL-PHYS-PUB-2011-11, CMS NOTE-2011/005, CERN | |
56 | G. Cowan, K. Cranmer, E. Gross, and O. Vitells | Asymptotic formulae for likelihood-based tests of new physics | EPJC 71 (2011) 1554, , [Erratum: Eur. Phys. J. C 73 (2013) 2501] | 1007.1727 |
57 | CMS Collaboration | Measurement of differential cross sections for Higgs boson production in the diphoton decay channel in pp collisions at $ \sqrt{s} $=8 TeV | EPJC 76 (2015) 13 | CMS-HIG-14-016 1508.07819 |
58 | F. Caola and K. Melnikov | Constraining the Higgs boson width with ZZ production at the LHC | PRD 88 (2013) 054024 | 1307.4935 |
59 | N. Kauer and G. Passarino | Inadequacy of zero-width approximation for a light Higgs boson signal | JHEP 08 (2012) 116 | 1206.4803 |
60 | J. M. Campbell, R. K. Ellis, and C. Williams | Bounding the Higgs width at the LHC using full analytic results for $ \mathrm{g}\mathrm{g}\to \mathrm{e^-}\mathrm{e^+} \mu^- \mu^+ $ | JHEP 04 (2014) 060 | 1311.3589 |
Compact Muon Solenoid LHC, CERN |