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| CMS-PAS-SUS-21-008 | ||
| Combined search for electroweak production of winos, binos, higgsinos, and sleptons in proton-proton collisions at $ \sqrt{s}= $ 13 TeV | ||
| CMS Collaboration | ||
| 24 March 2023 | ||
| Abstract: A combination of several searches for the electroweak production of winos, binos, higgsinos, and sleptons is presented. All searches use proton-proton collision data at $ \sqrt{s}= $ 13 TeV recorded with the CMS detector at the LHC during years 2016-2018. The analyzed data set corresponds to an integrated luminosity of 137 fb$ ^{-1} $. The results are interpreted in simplified models of chargino-neutralino, neutralino, or slepton pair production. In addition to the previously published searches, the combination includes results from an updated version of the search targeting events with two low-momentum leptons and missing transverse momentum. A parametric signal extraction is introduced that enhances the sensitivity to each signal hypothesis, along with a signal selection optimized to search for slepton pair production in models with compressed spectra. In addition to the models previously considered, the results of the combination are interpreted in a scenario where neutralinos and charginos in a mass-degenerate higgsino triplet are produced and decay to SM bosons and a bino-like LSP. The results are consistent with expectations from the standard model. The combination provides a more comprehensive coverage of the model parameter space than the individual searches, and adds sensitivity in the compressed mass parameter regions. | ||
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Links:
CDS record (PDF) ;
CADI line (restricted) ;
These preliminary results are superseded in this paper, Submitted to PRD. The superseded preliminary plots can be found here. |
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| Figures | |
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Figure 1:
Production of $ \tilde{\chi}_{1}^{\pm} $ and $ \tilde{\chi}_{2}^{0} $, with the $ \tilde{\chi}_{1}^{\pm} $ decaying to a W boson and a $ \tilde{\chi}_{1}^{0} $, and the $ \tilde{\chi}_{2}^{0} $ decaying to either a Z or H boson and a $ \tilde{\chi}_{1}^{0} $. |
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Figure 2:
Pair production of $ \tilde{\chi}_{1}^{0} \tilde{\chi}_{1}^{0} $ assuming the GMSB quasi-degenerate higgsino model. The $ \tilde{\chi}_{1}^{0} $ particles each decay to a $ \tilde{\mathrm{G}} $ with the emission of an SM gauge boson: (left) both Z, (center) one Z and the other H, or (right) both H. Soft fermions from decays of nearly degenerate neutralinos and charginos are omitted. |
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Figure 2-a:
Pair production of $ \tilde{\chi}_{1}^{0} \tilde{\chi}_{1}^{0} $ assuming the GMSB quasi-degenerate higgsino model. The $ \tilde{\chi}_{1}^{0} $ particles each decay to a $ \tilde{\mathrm{G}} $ with the emission of an SM gauge boson: (left) both Z, (center) one Z and the other H, or (right) both H. Soft fermions from decays of nearly degenerate neutralinos and charginos are omitted. |
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Figure 2-b:
Pair production of $ \tilde{\chi}_{1}^{0} \tilde{\chi}_{1}^{0} $ assuming the GMSB quasi-degenerate higgsino model. The $ \tilde{\chi}_{1}^{0} $ particles each decay to a $ \tilde{\mathrm{G}} $ with the emission of an SM gauge boson: (left) both Z, (center) one Z and the other H, or (right) both H. Soft fermions from decays of nearly degenerate neutralinos and charginos are omitted. |
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Figure 2-c:
Pair production of $ \tilde{\chi}_{1}^{0} \tilde{\chi}_{1}^{0} $ assuming the GMSB quasi-degenerate higgsino model. The $ \tilde{\chi}_{1}^{0} $ particles each decay to a $ \tilde{\mathrm{G}} $ with the emission of an SM gauge boson: (left) both Z, (center) one Z and the other H, or (right) both H. Soft fermions from decays of nearly degenerate neutralinos and charginos are omitted. |
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Figure 3:
Production and decay modes used for the higgsino-bino interpretations, showing (left) the production of a pair of charginos followed by their decays to W bosons and the LSP, (middle) the production of a pair of neutralinos followed by decays to H bosons and the LSP and (right) the production of chargino-neutralino pairs followed by decays of the charginos (neutralinos) to a W (H) boson and the LSP. |
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Figure 3-a:
Production and decay modes used for the higgsino-bino interpretations, showing (left) the production of a pair of charginos followed by their decays to W bosons and the LSP, (middle) the production of a pair of neutralinos followed by decays to H bosons and the LSP and (right) the production of chargino-neutralino pairs followed by decays of the charginos (neutralinos) to a W (H) boson and the LSP. |
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Figure 3-b:
Production and decay modes used for the higgsino-bino interpretations, showing (left) the production of a pair of charginos followed by their decays to W bosons and the LSP, (middle) the production of a pair of neutralinos followed by decays to H bosons and the LSP and (right) the production of chargino-neutralino pairs followed by decays of the charginos (neutralinos) to a W (H) boson and the LSP. |
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Figure 3-c:
Production and decay modes used for the higgsino-bino interpretations, showing (left) the production of a pair of charginos followed by their decays to W bosons and the LSP, (middle) the production of a pair of neutralinos followed by decays to H bosons and the LSP and (right) the production of chargino-neutralino pairs followed by decays of the charginos (neutralinos) to a W (H) boson and the LSP. |
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Figure 4:
Direct slepton pair production, with each slepton decaying into a lepton and a $ \tilde{\chi}_{1}^{0} $ LSP. |
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Figure 5:
The ``2/3$\ell $ soft'' dilepton mass spectrum for two mass hypotheses with the same NLSP mass (100 GeV) and different mass splittings $ \Delta m $ (40 or 10 GeV), both corresponding to analytical phase space only calculations. The distributions have a kinematic endpoint at the mass splitting. |
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Figure 6:
Post-fit distributions of the $ m_{\ell\ell} $ variable for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for signal mass points with $ \Delta m $ = 20 GeV. The pre-fit signal distribution is overlaid for illustration. |
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Figure 6-a:
Post-fit distributions of the $ m_{\ell\ell} $ variable for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for signal mass points with $ \Delta m $ = 20 GeV. The pre-fit signal distribution is overlaid for illustration. |
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Figure 6-b:
Post-fit distributions of the $ m_{\ell\ell} $ variable for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for signal mass points with $ \Delta m $ = 20 GeV. The pre-fit signal distribution is overlaid for illustration. |
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Figure 6-c:
Post-fit distributions of the $ m_{\ell\ell} $ variable for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for signal mass points with $ \Delta m $ = 20 GeV. The pre-fit signal distribution is overlaid for illustration. |
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Figure 6-d:
Post-fit distributions of the $ m_{\ell\ell} $ variable for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for signal mass points with $ \Delta m $ = 20 GeV. The pre-fit signal distribution is overlaid for illustration. |
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Figure 7:
Post-fit distributions of the $ m_{\ell\ell} $ variable for the low- (left) and medium- (right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``3 $ \ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for signal mass points with $ \Delta m $ = 20 GeV. The pre-fit signal distribution is overlaid for illustration. |
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Figure 7-a:
Post-fit distributions of the $ m_{\ell\ell} $ variable for the low- (left) and medium- (right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``3 $ \ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for signal mass points with $ \Delta m $ = 20 GeV. The pre-fit signal distribution is overlaid for illustration. |
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Figure 7-b:
Post-fit distributions of the $ m_{\ell\ell} $ variable for the low- (left) and medium- (right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``3 $ \ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for signal mass points with $ \Delta m $ = 20 GeV. The pre-fit signal distribution is overlaid for illustration. |
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Figure 8:
Post-fit distributions of the $ m_{\mathrm{T2}}(\ell\ell) $ variable are shown for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for the mass-point $ m_{\mathrm{NLSP}}=$ 125 GeV, $m_{\mathrm{LSP}}= $ 115 GeV. The pre-fit signal distribution is overlaid for illustration. Note that the signal distribution (purple line) is approximately flat across $ m_{\mathrm{T2}}(\ell\ell) $, by construction of the parametric binning procedure. The minimum value of $ m_{\mathrm{T2}}(\ell\ell) $, $ m_\chi = $ 100 GeV, is subtracted for the abscissa of the plot. |
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Figure 8-a:
Post-fit distributions of the $ m_{\mathrm{T2}}(\ell\ell) $ variable are shown for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for the mass-point $ m_{\mathrm{NLSP}}=$ 125 GeV, $m_{\mathrm{LSP}}= $ 115 GeV. The pre-fit signal distribution is overlaid for illustration. Note that the signal distribution (purple line) is approximately flat across $ m_{\mathrm{T2}}(\ell\ell) $, by construction of the parametric binning procedure. The minimum value of $ m_{\mathrm{T2}}(\ell\ell) $, $ m_\chi = $ 100 GeV, is subtracted for the abscissa of the plot. |
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Figure 8-b:
Post-fit distributions of the $ m_{\mathrm{T2}}(\ell\ell) $ variable are shown for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for the mass-point $ m_{\mathrm{NLSP}}=$ 125 GeV, $m_{\mathrm{LSP}}= $ 115 GeV. The pre-fit signal distribution is overlaid for illustration. Note that the signal distribution (purple line) is approximately flat across $ m_{\mathrm{T2}}(\ell\ell) $, by construction of the parametric binning procedure. The minimum value of $ m_{\mathrm{T2}}(\ell\ell) $, $ m_\chi = $ 100 GeV, is subtracted for the abscissa of the plot. |
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Figure 8-c:
Post-fit distributions of the $ m_{\mathrm{T2}}(\ell\ell) $ variable are shown for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for the mass-point $ m_{\mathrm{NLSP}}=$ 125 GeV, $m_{\mathrm{LSP}}= $ 115 GeV. The pre-fit signal distribution is overlaid for illustration. Note that the signal distribution (purple line) is approximately flat across $ m_{\mathrm{T2}}(\ell\ell) $, by construction of the parametric binning procedure. The minimum value of $ m_{\mathrm{T2}}(\ell\ell) $, $ m_\chi = $ 100 GeV, is subtracted for the abscissa of the plot. |
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Figure 8-d:
Post-fit distributions of the $ m_{\mathrm{T2}}(\ell\ell) $ variable are shown for the low- (upper left), medium- (upper right), high- (bottom left) and ultra- (bottom right) $ p_{\mathrm{T}}^\text{miss} $ bins in the ``2$\ell $ soft'' signal region of Ref. [17]. These distributions are based on the parametric binnings derived for the mass-point $ m_{\mathrm{NLSP}}=$ 125 GeV, $m_{\mathrm{LSP}}= $ 115 GeV. The pre-fit signal distribution is overlaid for illustration. Note that the signal distribution (purple line) is approximately flat across $ m_{\mathrm{T2}}(\ell\ell) $, by construction of the parametric binning procedure. The minimum value of $ m_{\mathrm{T2}}(\ell\ell) $, $ m_\chi = $ 100 GeV, is subtracted for the abscissa of the plot. |
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Figure 9:
Observed and expected yields across the search regions in the ``$ \geq$ 3$\ell $" search in category A, events with three light leptons at least two of which form an OSSF pair, after the requirement on the leading lepton $ p_{\mathrm{T}} $ to be greater than 30 GeV is applied. |
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Figure 10:
Observed and expected yields across the SRs of the ``$ \geq$ 3$\ell $" search in category B, events with three light leptons and no OSSF pair, after the requirement on the leading lepton $ p_{\mathrm{T}} $ to be greater than 30 GeV is applied. |
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Figure 11:
Cross section limits with expected and observed exclusion boundaries in the model parameter space, for neutralino-chargino production in the WZ topology for the full parameter space (upper left) as well as the compressed region (upper right), the WH topology (lower left), and the mixed topology with 50% branching fraction to WZ and WH (lower right). |
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Figure 11-a:
Cross section limits with expected and observed exclusion boundaries in the model parameter space, for neutralino-chargino production in the WZ topology for the full parameter space (upper left) as well as the compressed region (upper right), the WH topology (lower left), and the mixed topology with 50% branching fraction to WZ and WH (lower right). |
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Figure 11-b:
Cross section limits with expected and observed exclusion boundaries in the model parameter space, for neutralino-chargino production in the WZ topology for the full parameter space (upper left) as well as the compressed region (upper right), the WH topology (lower left), and the mixed topology with 50% branching fraction to WZ and WH (lower right). |
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Figure 11-c:
Cross section limits with expected and observed exclusion boundaries in the model parameter space, for neutralino-chargino production in the WZ topology for the full parameter space (upper left) as well as the compressed region (upper right), the WH topology (lower left), and the mixed topology with 50% branching fraction to WZ and WH (lower right). |
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Figure 11-d:
Cross section limits with expected and observed exclusion boundaries in the model parameter space, for neutralino-chargino production in the WZ topology for the full parameter space (upper left) as well as the compressed region (upper right), the WH topology (lower left), and the mixed topology with 50% branching fraction to WZ and WH (lower right). |
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Figure 12:
Exclusion contours for the individual analyses targeting the WZ topology for the full parameter space (upper left) the corresponding compressed region (upper right), and the WH topology (lower left). The combined contours for these two topologies are also shown. The combined contours for these and the mixed topology are overlaid in the lower right plot. The decay modes assumed for each contour are given in the legends. |
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Figure 12-a:
Exclusion contours for the individual analyses targeting the WZ topology for the full parameter space (upper left) the corresponding compressed region (upper right), and the WH topology (lower left). The combined contours for these two topologies are also shown. The combined contours for these and the mixed topology are overlaid in the lower right plot. The decay modes assumed for each contour are given in the legends. |
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Figure 12-b:
Exclusion contours for the individual analyses targeting the WZ topology for the full parameter space (upper left) the corresponding compressed region (upper right), and the WH topology (lower left). The combined contours for these two topologies are also shown. The combined contours for these and the mixed topology are overlaid in the lower right plot. The decay modes assumed for each contour are given in the legends. |
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Figure 12-c:
Exclusion contours for the individual analyses targeting the WZ topology for the full parameter space (upper left) the corresponding compressed region (upper right), and the WH topology (lower left). The combined contours for these two topologies are also shown. The combined contours for these and the mixed topology are overlaid in the lower right plot. The decay modes assumed for each contour are given in the legends. |
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Figure 12-d:
Exclusion contours for the individual analyses targeting the WZ topology for the full parameter space (upper left) the corresponding compressed region (upper right), and the WH topology (lower left). The combined contours for these two topologies are also shown. The combined contours for these and the mixed topology are overlaid in the lower right plot. The decay modes assumed for each contour are given in the legends. |
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Figure 13:
The analysis with the best exclusion limit for each point in the plane for the WZ topology (upper left), the WH topology (upper right), and the mixed topology with 50% branching fraction to WZ and WH (bottom). |
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Figure 13-a:
The analysis with the best exclusion limit for each point in the plane for the WZ topology (upper left), the WH topology (upper right), and the mixed topology with 50% branching fraction to WZ and WH (bottom). |
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Figure 13-b:
The analysis with the best exclusion limit for each point in the plane for the WZ topology (upper left), the WH topology (upper right), and the mixed topology with 50% branching fraction to WZ and WH (bottom). |
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Figure 13-c:
The analysis with the best exclusion limit for each point in the plane for the WZ topology (upper left), the WH topology (upper right), and the mixed topology with 50% branching fraction to WZ and WH (bottom). |
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Figure 14:
Expected and observed exclusion limits for the neutralino-neutralino production for the ZZ topology (upper left), the HH topology (upper right), and the mixed topology with 50% branching fraction to H and Z (lower). |
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Figure 14-a:
Expected and observed exclusion limits for the neutralino-neutralino production for the ZZ topology (upper left), the HH topology (upper right), and the mixed topology with 50% branching fraction to H and Z (lower). |
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Figure 14-b:
Expected and observed exclusion limits for the neutralino-neutralino production for the ZZ topology (upper left), the HH topology (upper right), and the mixed topology with 50% branching fraction to H and Z (lower). |
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Figure 14-c:
Expected and observed exclusion limits for the neutralino-neutralino production for the ZZ topology (upper left), the HH topology (upper right), and the mixed topology with 50% branching fraction to H and Z (lower). |
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Figure 15:
NLSP-mass exclusion limit for neutralino-neutralino production as a function of the branching fraction to the H boson. Left: expected and observed limits for the combination of the searches, shown together with the observed limits of the combination [25] based on the 2016 CMS data. Right: expected and observed exclusion limits for the combination in comparison with those of the input searches. |
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Figure 15-a:
NLSP-mass exclusion limit for neutralino-neutralino production as a function of the branching fraction to the H boson. Left: expected and observed limits for the combination of the searches, shown together with the observed limits of the combination [25] based on the 2016 CMS data. Right: expected and observed exclusion limits for the combination in comparison with those of the input searches. |
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Figure 15-b:
NLSP-mass exclusion limit for neutralino-neutralino production as a function of the branching fraction to the H boson. Left: expected and observed limits for the combination of the searches, shown together with the observed limits of the combination [25] based on the 2016 CMS data. Right: expected and observed exclusion limits for the combination in comparison with those of the input searches. |
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Figure 16:
The analysis with the best limit exclusion for each point in the branching fraction-$ m_{\tilde{\chi}_{1}^{0}} $ plane for neutralino-neutralino production. |
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Figure 17:
Cross section upper limit in the mass plane of the higgsino-bino model, and the expected and observed exclusion limits. The model assumes mass-degenerate higgsino-like $ \tilde{\chi}_{2}^{0} $, $ \tilde{\chi}_{3}^{0} $, and $ \tilde{\chi}_{1}^{\pm} $ that decay to a bino-like $ \tilde{\chi}_{1}^{0} $ and an SM boson. |
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Figure 18:
Mass-plane cross section upper limit for direct slepton pair production, with observed and expected exclusion limits: (left) the full mass plane from the combination, and (right) the compressed region, obtained by the ``2/3$\ell $ soft'' search. |
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Figure 18-a:
Mass-plane cross section upper limit for direct slepton pair production, with observed and expected exclusion limits: (left) the full mass plane from the combination, and (right) the compressed region, obtained by the ``2/3$\ell $ soft'' search. |
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Figure 18-b:
Mass-plane cross section upper limit for direct slepton pair production, with observed and expected exclusion limits: (left) the full mass plane from the combination, and (right) the compressed region, obtained by the ``2/3$\ell $ soft'' search. |
| Tables | |
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Table 1:
Definition of the lepton multiplicity and $ p_{\mathrm{T}}^\text{miss, corr} $ SRs of the ``2/3$\ell $ soft'' search. The last line shows the $ m_{\ell\ell} $ binning used in Ref. [17]. The boundaries are indicated in GeVns. Events in the Low-$ p_{\mathrm{T}}^\text{miss} $ SR must additionally have $ p_{\mathrm{T}}^\text{miss} > $ 125 GeV. |
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Table 2:
Definitions of the SRs in category A, on-Z. |
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Table 3:
Definitions of the SRs in category A, off-Z. |
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Table 4:
Summary of the searches considered in the combination and the SRs that contribute to the interpretation of each signal model and topology. The abbreviation 2$\ell $ non-res. refers to the ``2$\ell $ non-resonant'' search. For the ``2$\ell $ on-Z'' analysis, EW refers to the resolved and boosted VZ SRs and the HZ SR. For the ``2$\ell $ non-resonant'' search, Slepton refers to the two dedicated slepton SRs, those requiring $ N_{\text{jet}}= $ 0 and $ N_{\text{jet}} > $ 0. For the ``$ \geq$ 3\ell $'' search, A(NN) indicates SR A with the parametric neural network signal extraction. |
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Table 5:
Sources of systematic uncertainties and the level of correlation between analyses. [4pt] Notes: 1. The WZ background normalization is correlated between the ``$ \geq$ 3$\ell $" [18] and the ``2/3$\ell $ soft'' [17] searches. 2. Except for slepton pair production, for which the two contributing searches, ``2/3$\ell $ soft'' [17] and ``2$\ell $ non-resonant'' [15], cover disjoint regions of the model parameter space. |
| Summary |
| A number of searches for new physics have been optimized and combined in different final states in proton-proton collision data at $ \sqrt{s}= $ 13 TeV, recorded with the CMS detector at the Large Hadron Collider and corresponding to an integrated luminosity of 137 fb$ ^{-1} $. No significant deviation from the standard model expectation has been observed. Limits are set on a variety of simplified models of supersymmetry (SUSY) that involve the electroweak production of supersymmetric partners of electroweak gauge or Higgs bosons. Specifically, limits are set on the production of gaugino-like chargino-neutralino pairs, higgsino-like neutralino pair production in a gauge-mediated SUSY breaking inspired scenario, a higgsino-bino interpretation, and slepton pair production. In the case of chargino-neutralino pair production, for an LSP $ \tilde{\chi}_{1}^{0} $ with a mass up to 50 GeV, the combined result gives an observed (expected) limit in $ m_{\tilde{\chi}_{1}^{\pm}} $ of about 875 (950) GeV for the WZ final state, 990 (1075) GeV for the WH final state, and 875 (1000) GeV for a mixed topology, extending the previous CMS result [25] by 225 GeV, 510 GeV, and 340 GeV, respectively, for the three topologies. For the higgsino pair production, the expected mass exclusion limit varies between about 600 and 950 GeV, being least stringent around $ \mathcal{B}(\tilde{\chi}_{1}^{0} \to \mathrm{H}\tilde{\mathrm{G}}) = $ 0.4. The observed limit ranges between about 750 and 1025 GeV, allowing the exclusion of masses below 750 GeV independent of this branching fraction. This extends the previous result [25] by 100 GeV. A higgsino-bino model that assumes mass degenerate higgsino-like $ \tilde{\chi}_{2}^{0} $, $ \tilde{\chi}_{3}^{0} $, and $ \tilde{\chi}_{1}^{\pm} $ decaying to a bino-like $ \tilde{\chi}_{1}^{0} $ and an SM boson is excluded for $ m_{\tilde{\chi}_{1}^{\pm}}=m_{\tilde{\chi}_{2}^{0}} $ between 225 and 800 GeV for a $ \tilde{\chi}_{1}^{0} $ mass below 50 GeV. In general for the models considered in this combination, chargino masses are excluded up to 990 GeV, while higgsino masses are excluded up to 1000 GeV. The improvement is between 100--510 GeV with respect to the previously set exclusion limits [25]. Additionally, the results presented here set limits on direct slepton pair production. A dedicated search added for this note explores the parameter space in the most compressed region. For $ \Delta m({\tilde{\ell}},\tilde{\chi}_{1}^{0})= $ 5 GeV slepton masses up to 215 GeV are excluded. The combination yields an observed (expected) exclusion in the slepton mass of about 130--700 (110--720) GeV, for $ m_{\tilde{\chi}_{1}^{0}} < $ 50 GeV. |
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