CMS-HIG-17-012 ; CERN-EP-2018-009 | ||
Search for a new scalar resonance decaying to a pair of Z bosons in proton-proton collisions at $\sqrt{s} = $ 13 TeV | ||
CMS Collaboration | ||
5 April 2018 | ||
JHEP 06 (2018) 127 [Erratum] | ||
Abstract: A search for a new scalar resonance decaying to a pair of Z bosons is performed in the mass range from 130 GeV to 3 TeV, and for various width scenarios. The analysis is based on proton-proton collisions recorded by the CMS experiment at the LHC in 2016, corresponding to an integrated luminosity of 35.9 fb$^{-1}$ at a center-of-mass energy of 13 TeV. The Z boson pair decays are reconstructed using the $ 4 \ell$, $ 2 \ell 2 \mathrm{q} $, and $ 2\ell 2\nu$ final states, where $\ell = $ e or $\mu$. Both gluon fusion and electroweak production of the scalar resonance are considered, with a free parameter describing their relative cross sections. A dedicated categorization of events, based on the kinematic properties of associated jets, and matrix element techniques are employed for an optimal signal and background separation. A description of the interference between signal and background amplitudes for a resonance of an arbitrary width is included. No significant excess of events with respect to the standard model expectation is observed and limits are set on the product of the cross section for a new scalar boson and the branching fraction for its decay to ZZ for a large range of masses and widths. | ||
Links: e-print arXiv:1804.01939 [hep-ex] (PDF) ; CDS record ; inSPIRE record ; HepData record ; CADI line (restricted) ; |
Figures | |
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Figure 1:
Illustration of an X boson production from ${{\mathrm {g}} {\mathrm {g}} \mathrm {F}}$, $ {\mathrm {g}} {\mathrm {g}} \to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}} \to (\ell ^+\ell ^-)(\mathrm{ f\overline {f} })$ (left), and VBF, $ {\mathrm {q}}{{\mathrm {q}}^\prime}\to {\mathrm {q}}{{\mathrm {q}}^\prime} {\mathrm {X}}\to {\mathrm {q}}{{\mathrm {q}}^\prime} {\mathrm {Z}} {\mathrm {Z}} $ (right). The five angles shown in blue and the invariant masses of the two vector bosons shown in green fully characterize either the production or the decay chain. The angles are defined in either the X or V boson rest frames [36,38]. |
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Figure 1-a:
Illustration of an X boson production from ${{\mathrm {g}} {\mathrm {g}} \mathrm {F}}$, $ {\mathrm {g}} {\mathrm {g}} \to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}} \to (\ell ^+\ell ^-)(\mathrm{ f\overline {f} })$. The five angles shown in blue and the invariant masses of the two vector bosons shown in green fully characterize either the production or the decay chain. The angles are defined in either the X or V boson rest frames [36,38]. |
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Figure 1-b:
Illustration of an X boson production from VBF, $ {\mathrm {q}}{{\mathrm {q}}^\prime}\to {\mathrm {q}}{{\mathrm {q}}^\prime} {\mathrm {X}}\to {\mathrm {q}}{{\mathrm {q}}^\prime} {\mathrm {Z}} {\mathrm {Z}} $. The five angles shown in blue and the invariant masses of the two vector bosons shown in green fully characterize either the production or the decay chain. The angles are defined in either the X or V boson rest frames [36,38]. |
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Figure 2:
Distributions of the four lepton invariant mass in the untagged (upper left plot), VBF-tagged (upper right plot) and RSE (lower plot) categories. Signal expectations including the interference effect for several mass and width hypotheses are shown. The signals are normalized to the expected upper limit of the cross section derived from this final state. Lower panels show the ratio between data and background estimation in each case. |
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Figure 2-a:
Distribution of the four lepton invariant mass in the untagged category. Signal expectations including the interference effect for several mass and width hypotheses are shown. The signals are normalized to the expected upper limit of the cross section derived from this final state. The lower panel shows the ratio between data and background estimation. |
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Figure 2-b:
Distribution of the four lepton invariant mass in the VBF-tagged category. Signal expectations including the interference effect for several mass and width hypotheses are shown. The signals are normalized to the expected upper limit of the cross section derived from this final state. The lower panel shows the ratio between data and background estimation. |
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Figure 2-c:
Distribution of the four lepton invariant mass in the RSE category. Signal expectations including the interference effect for several mass and width hypotheses are shown. The signals are normalized to the expected upper limit of the cross section derived from this final state. The lower panel shows the ratio between data and background estimation. |
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Figure 3:
Distributions of ${\cal D}_{\mathrm {bkg}}^{\mathrm {kin}}$ for all selected events. Signal expectations including the interference effect for several mass and width hypotheses are shown. The signals are normalized to a total of 400 events. |
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Figure 4:
Distributions of the invariant mass ${m_{{\mathrm {Z}} {\mathrm {Z}}}}$ in the signal region for the merged (left) and resolved (right) case for the different categories in the $2{\ell}2 {\mathrm {q}}$ channel. The points represent the data, the stacked histograms the expected backgrounds from simulation, and the open histograms the expected signal. The blue hatched bands refer to the sum of background estimates derived from either simulation or control samples in data, as described in the text. Lower panels show the ratio between data and background estimation in each case. |
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Figure 4-a:
Distribution of the invariant mass ${m_{{\mathrm {Z}} {\mathrm {Z}}}}$ in the signal region for the merged case for the untagged category in the $2{\ell}2 {\mathrm {q}}$ channel. The points represent the data, the stacked histograms the expected backgrounds from simulation, and the open histogram the expected signal. The blue hatched band refers to the sum of background estimates derived from either simulation or control samples in data, as described in the text. The lower panel shows the ratio between data and background estimation. |
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Figure 4-b:
Distribution of the invariant mass ${m_{{\mathrm {Z}} {\mathrm {Z}}}}$ in the signal region for the resolved case for the untagged category in the $2{\ell}2 {\mathrm {q}}$ channel. The points represent the data, the stacked histograms the expected backgrounds from simulation, and the open histogram the expected signal. The blue hatched band refers to the sum of background estimates derived from either simulation or control samples in data, as described in the text. The lower panel shows the ratio between data and background estimation. |
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Figure 4-c:
Distribution of the invariant mass ${m_{{\mathrm {Z}} {\mathrm {Z}}}}$ in the signal region for the merged case for the VBF-tagged category in the $2{\ell}2 {\mathrm {q}}$ channel. The points represent the data, the stacked histograms the expected backgrounds from simulation, and the open histogram the expected signal. The blue hatched band refers to the sum of background estimates derived from either simulation or control samples in data, as described in the text. The lower panel shows the ratio between data and background estimation. |
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Figure 4-d:
Distribution of the invariant mass ${m_{{\mathrm {Z}} {\mathrm {Z}}}}$ in the signal region for the resolved case for the VBF-tagged category in the $2{\ell}2 {\mathrm {q}}$ channel. The points represent the data, the stacked histograms the expected backgrounds from simulation, and the open histogram the expected signal. The blue hatched band refers to the sum of background estimates derived from either simulation or control samples in data, as described in the text. The lower panel shows the ratio between data and background estimation. |
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Figure 4-e:
Distribution of the invariant mass ${m_{{\mathrm {Z}} {\mathrm {Z}}}}$ in the signal region for the merged case for the b-tagged category in the $2{\ell}2 {\mathrm {q}}$ channel. The points represent the data, the stacked histograms the expected backgrounds from simulation, and the open histogram the expected signal. The blue hatched band refers to the sum of background estimates derived from either simulation or control samples in data, as described in the text. The lower panel shows the ratio between data and background estimation. |
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Figure 4-f:
Distribution of the invariant mass ${m_{{\mathrm {Z}} {\mathrm {Z}}}}$ in the signal region for the resolved case for the b-tagged category in the $2{\ell}2 {\mathrm {q}}$ channel. The points represent the data, the stacked histograms the expected backgrounds from simulation, and the open histogram the expected signal. The blue hatched band refers to the sum of background estimates derived from either simulation or control samples in data, as described in the text. The lower panel shows the ratio between data and background estimation. |
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Figure 5:
Distributions of the ${\mathcal {D}_\textrm {bkg}^\textrm {Zjj}}$ (left) and ${\mathcal {D}_\textrm {2jet}^\textrm {VBF}}$ (right) discriminants in the signal region for the resolved selection. The points represent the data, the stacked histograms the expected background from simulation, and the open histograms the expected signal. |
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Figure 5-a:
Distribution of the ${\mathcal {D}_\textrm {bkg}^\textrm {Zjj}}$ discriminant in the signal region for the resolved selection. The points represent the data, the stacked histograms the expected background from simulation, and the open histogram the expected signal. |
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Figure 5-b:
Distribution of the ${\mathcal {D}_\textrm {2jet}^\textrm {VBF}}$ discriminant in the signal region for the resolved selection. The points represent the data, the stacked histograms the expected background from simulation, and the open histogram the expected signal. |
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Figure 6:
Distributions of the transverse mass ${m_{\mathrm {T}}}$ in the signal region for the different analysis categories for the 2$\ell $2$\nu $ channel, in the ee (left) and $\mu \mu $ final states (right). The points represent the data and the stacked histograms the expected background. The open histograms show the expected gluon fusion and VBF signals for the product of cross section and branching fraction equal to $\sigma ({\mathrm {p}} {\mathrm {p}}\to {\mathrm {H}} \to {\mathrm {Z}} {\mathrm {Z}})= $ 50 fb. Lower panels show the ratio of data to the expected background. The shaded areas show the systematic and total combined statistical and systematic uncertainties in the background estimation. |
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Figure 6-a:
Distribution of the transverse mass ${m_{\mathrm {T}}}$ in the signal region for the 0 jet category for the 2$\ell $2$\nu $ channel, in the ee final state. The points represent the data and the stacked histograms the expected background. The open histogram shows the expected gluon fusion and VBF signals for the product of cross section and branching fraction equal to $\sigma ({\mathrm {p}} {\mathrm {p}}\to {\mathrm {H}} \to {\mathrm {Z}} {\mathrm {Z}})= $ 50 fb. The lower panel shows the ratio of data to the expected background. The shaded areas show the systematic and total combined statistical and systematic uncertainties in the background estimation. |
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Figure 6-b:
Distribution of the transverse mass ${m_{\mathrm {T}}}$ in the signal region for the 0 jet category for the 2$\ell $2$\nu $ channel, in the $\mu \mu $ final state. The points represent the data and the stacked histograms the expected background. The open histogram shows the expected gluon fusion and VBF signals for the product of cross section and branching fraction equal to $\sigma ({\mathrm {p}} {\mathrm {p}}\to {\mathrm {H}} \to {\mathrm {Z}} {\mathrm {Z}})= $ 50 fb. The lower panel shows the ratio of data to the expected background. The shaded areas show the systematic and total combined statistical and systematic uncertainties in the background estimation. |
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Figure 6-c:
Distribution of the transverse mass ${m_{\mathrm {T}}}$ in the signal region for the $\geq$1 jet category for the 2$\ell $2$\nu $ channel, in the ee final state. The points represent the data and the stacked histograms the expected background. The open histogram shows the expected gluon fusion and VBF signals for the product of cross section and branching fraction equal to $\sigma ({\mathrm {p}} {\mathrm {p}}\to {\mathrm {H}} \to {\mathrm {Z}} {\mathrm {Z}})= $ 50 fb. The lower panel shows the ratio of data to the expected background. The shaded areas show the systematic and total combined statistical and systematic uncertainties in the background estimation. |
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Figure 6-d:
Distribution of the transverse mass ${m_{\mathrm {T}}}$ in the signal region for the $\geq$1 jet category for the 2$\ell $2$\nu $ channel, in the $\mu \mu $ final state. The points represent the data and the stacked histograms the expected background. The open histogram shows the expected gluon fusion and VBF signals for the product of cross section and branching fraction equal to $\sigma ({\mathrm {p}} {\mathrm {p}}\to {\mathrm {H}} \to {\mathrm {Z}} {\mathrm {Z}})= $ 50 fb. The lower panel shows the ratio of data to the expected background. The shaded areas show the systematic and total combined statistical and systematic uncertainties in the background estimation. |
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Figure 6-e:
Distribution of the transverse mass ${m_{\mathrm {T}}}$ in the signal region for the VBF-tagged category for the 2$\ell $2$\nu $ channel, in the ee final state. The points represent the data and the stacked histograms the expected background. The open histogram shows the expected gluon fusion and VBF signals for the product of cross section and branching fraction equal to $\sigma ({\mathrm {p}} {\mathrm {p}}\to {\mathrm {H}} \to {\mathrm {Z}} {\mathrm {Z}})= $ 50 fb. The lower panel shows the ratio of data to the expected background. The shaded areas show the systematic and total combined statistical and systematic uncertainties in the background estimation. |
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Figure 6-f:
Distribution of the transverse mass ${m_{\mathrm {T}}}$ in the signal region for the VBF-tagged category for the 2$\ell $2$\nu $ channel, in the $\mu \mu $ final state. The points represent the data and the stacked histograms the expected background. The open histogram shows the expected gluon fusion and VBF signals for the product of cross section and branching fraction equal to $\sigma ({\mathrm {p}} {\mathrm {p}}\to {\mathrm {H}} \to {\mathrm {Z}} {\mathrm {Z}})= $ 50 fb. The lower panel shows the ratio of data to the expected background. The shaded areas show the systematic and total combined statistical and systematic uncertainties in the background estimation. |
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Figure 7:
The product of efficiency and acceptance for signal events to pass the $ {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}\to 4\ell $ (upper plots) and $ {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}\to 2\ell 2 {\mathrm {q}}$ (lower plots) selection as a function of the generated mass $m_{{\mathrm {Z}} {\mathrm {Z}}}^{\mathrm {Gen}}$, from ${{\mathrm {g}} {\mathrm {g}} \mathrm {F}}$ (left) and VBF (right) production modes. |
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Figure 7-a:
The product of efficiency and acceptance for signal events to pass the $ {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}\to 4\ell $ selection as a function of the generated mass $m_{{\mathrm {Z}} {\mathrm {Z}}}^{\mathrm {Gen}}$, from the ${{\mathrm {g}} {\mathrm {g}} \mathrm {F}}$ production mode. |
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Figure 7-b:
The product of efficiency and acceptance for signal events to pass the $ {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}\to 4\ell $ selection as a function of the generated mass $m_{{\mathrm {Z}} {\mathrm {Z}}}^{\mathrm {Gen}}$, from the VBF production mode. |
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Figure 7-c:
The product of efficiency and acceptance for signal events to pass the $ {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}\to 2\ell 2 {\mathrm {q}}$ selection as a function of the generated mass $m_{{\mathrm {Z}} {\mathrm {Z}}}^{\mathrm {Gen}}$, from the ${{\mathrm {g}} {\mathrm {g}} \mathrm {F}}$ production mode. |
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Figure 7-d:
The product of efficiency and acceptance for signal events to pass the $ {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}\to 2\ell 2 {\mathrm {q}}$ selection as a function of the generated mass $m_{{\mathrm {Z}} {\mathrm {Z}}}^{\mathrm {Gen}}$, from the VBF production mode. |
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Figure 8:
Parameterizations of the four lepton invariant mass for ${{\mathrm {g}} {\mathrm {g}} \mathrm {F}}$ (left) and VBF (right) production modes, for $ {m_{{\mathrm {X}}}} = $ 450 GeV, $ {\Gamma _{{\mathrm {X}}}} = $ 10 GeV. The interference contributions from H(125) and $ {\mathrm {g}} {\mathrm {g}} \to {\mathrm {Z}} {\mathrm {Z}}$ or $\mathrm{V} {\mathrm {V}}\to {\mathrm {Z}} {\mathrm {Z}}$ background are also shown. The signal cross section used corresponds to the limit obtained in the $4\ell $ final state. |
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Figure 8-a:
Parameterizations of the four lepton invariant mass for the ${{\mathrm {g}} {\mathrm {g}} \mathrm {F}}$ production mode, for $ {m_{{\mathrm {X}}}} = $ 450 GeV, $ {\Gamma _{{\mathrm {X}}}} = $ 10 GeV. The interference contributions from H(125) and $ {\mathrm {g}} {\mathrm {g}} \to {\mathrm {Z}} {\mathrm {Z}}$ or $\mathrm{V} {\mathrm {V}}\to {\mathrm {Z}} {\mathrm {Z}}$ background are also shown. The signal cross section used corresponds to the limit obtained in the $4\ell $ final state. |
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Figure 8-b:
Parameterizations of the four lepton invariant mass for the VBF production mode, for $ {m_{{\mathrm {X}}}} = $ 450 GeV, $ {\Gamma _{{\mathrm {X}}}} = $ 10 GeV. The interference contributions from H(125) and $ {\mathrm {g}} {\mathrm {g}} \to {\mathrm {Z}} {\mathrm {Z}}$ or $\mathrm{V} {\mathrm {V}}\to {\mathrm {Z}} {\mathrm {Z}}$ background are also shown. The signal cross section used corresponds to the limit obtained in the $4\ell $ final state. |
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Figure 9:
Distribution of the missing transverse energy ${{p_{\mathrm {T}}} ^\text {miss}}$ in the dilepton signal region. The points represent the data and the stacked histograms the expected backgrounds. The lower panel shows the ratio between data and background estimation. |
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Figure 10:
Expected and observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and for several $\Gamma _ {\mathrm {X}}$ values with $f_{\mathrm {VBF}}$ as a free parameter (left) and fixed to 1 (right). The results are shown for $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels separately and combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
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Figure 10-a:
Expected and observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and for $\Gamma _ {\mathrm {X}}= $ 0 GeV with $f_{\mathrm {VBF}}$ as a free parameter. The results are shown for $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels separately and combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
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Figure 10-b:
Expected and observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and for $\Gamma _ {\mathrm {X}}= $ 0 GeV with $f_{\mathrm {VBF}}$ fixed to 1. The results are shown for $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels separately and combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
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Figure 10-c:
Expected and observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and for $\Gamma _ {\mathrm {X}}= $ 10 GeV with $f_{\mathrm {VBF}}$ as a free parameter. The results are shown for $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels separately and combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
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Figure 10-d:
Expected and observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and for $\Gamma _ {\mathrm {X}}= $ 10 GeV with $f_{\mathrm {VBF}}$ fixed to 1. The results are shown for $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels separately and combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
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Figure 10-e:
Expected and observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and for $\Gamma _ {\mathrm {X}}= $ 100 GeV with $f_{\mathrm {VBF}}$ as a free parameter. The results are shown for $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels separately and combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
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Figure 10-f:
Expected and observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and for $\Gamma _ {\mathrm {X}}= $ 100 GeV with $f_{\mathrm {VBF}}$ fixed to 1. The results are shown for $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels separately and combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
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Figure 11:
Observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and $\Gamma _ {\mathrm {X}}/m_ {\mathrm {X}}$ values with $f_{\mathrm {VBF}}$ as a free parameter (left) and fixed to 1 (right). The results are shown for the $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
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Figure 11-a:
Observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and $\Gamma _ {\mathrm {X}}/m_ {\mathrm {X}}$ values with $f_{\mathrm {VBF}}$ as a free parameter. The results are shown for the $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
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Figure 11-b:
Observed upper limits at the 95% CL on the $ {\mathrm {p}} {\mathrm {p}}\to {\mathrm {X}}\to {\mathrm {Z}} {\mathrm {Z}}$ cross section as a function of $m_ {\mathrm {X}}$ and $\Gamma _ {\mathrm {X}}/m_ {\mathrm {X}}$ values with $f_{\mathrm {VBF}}$ fixed to 1. The results are shown for the $4\ell $, $2\ell 2 {\mathrm {q}}$, and $2\ell 2\nu $ channels combined. The reported cross section corresponds to the signal only contribution in the absence of interference. |
Tables | |
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Table 1:
Sources of uncertainties considered in each of the channels included in this analysis. Uncertainties are given in percent. The numbers shown as ranges represent the uncertainties in different final states or categories. Most uncertainties affect the normalizations of the background estimations or simulated event yields, and those that affect the shape of kinematic distributions as well are labeled with (*). |
Summary |
A search for a new scalar resonance decaying to a pair of Z bosons is performed for a range of masses between 130 GeV and 3 TeV with the full data set recorded by the CMS experiment at 13 TeV during 2016 and corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Three final states $\mathrm{Z}\mathrm{Z}\to 4\ell$, $2\ell2\mathrm{q}$, and $2\ell2\nu$ are combined in the analysis, where $\ell = $ e or $\mu$. Both gluon fusion and electroweak production of the scalar resonance are considered with a free parameter describing their relative cross sections. A dedicated categorization of events based on the kinematic properties of the associated jets is used to improve the sensitivity of the search. A description of the interference between signal and background amplitudes for a resonance of an arbitrary width is included. No significant excess of events over the SM expectation is observed and limits are set on the product of the cross section and the branching fraction for its decay to ZZ for a wide range of masses and widths, and for different production mechanisms. |
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Compact Muon Solenoid LHC, CERN |