CMS-PAS-EXO-16-027 | ||

Search for resonant production of high mass photon pairs using 12.9 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} =$ 13 TeV and combined interpretation of searches at 8 and 13 TeV. | ||

CMS Collaboration | ||

August 2016 | ||

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Abstract:
We report on a search for resonant production of high mass photon pairs. The search employs 12.9 fb$^{-1}$ of pp collision data collected by the CMS experiment in 2016 at a centre-of-mass energy of 13 TeV. It is aimed at spin-0 and spin-2 resonances of mass between 0.5 and 4.5 TeV and width, relative to the mass, up to $ 5.6 \times 10^{-2} $. The results of the search are combined statistically with those previously obtained by the CMS collaboration at $\sqrt{s}= $ 8 and 13 TeV. Limits are set on scalar resonances produced through gluon-gluon fusion, and on Randall-Sundrum gravitons. No significant excess is observed over the standard model predictions.
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Links:
CDS record (PDF) ;
inSPIRE record ;
CADI line (restricted) ;
These preliminary results are superseded in this paper, PLB 767 (2017) 147.The superseded preliminary plots can be found here. |

Figures | Summary | Additional Figures | References | CMS Publications |
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Figures | |

png pdf |
Figure 1-a:
Comparison between the predicted and observed invariant mass distribution of electron pairs obtained after the application of energy scale, resolution and identification efficiency corrections. Distributions are shown for events where both electrons are reconstructed in the barrel (a) and events where one electron is in an endcap (b). |

png pdf |
Figure 1-b:
Comparison between the predicted and observed invariant mass distribution of electron pairs obtained after the application of energy scale, resolution and identification efficiency corrections. Distributions are shown for events where both electrons are reconstructed in the barrel (a) and events where one electron is in an endcap (b). |

png pdf |
Figure 2-a:
Observed invariant mass spectra for the EBEB (a) and EBEE (b). No event with $ {m_{\gamma \gamma }} > $ 2000 GeV is selected in the analysis. The results of a likelihood fit to the background-only hypothesis are also shown. The shaded regions show the 1 and 2 standard deviation uncertainty bands associated with the fit, and reflect the statistical uncertainty of the data. The lower panels show the difference between the data and fit, divided by the statistical uncertainty in the data points. |

png pdf |
Figure 2-b:
Observed invariant mass spectra for the EBEB (a) and EBEE (b). No event with $ {m_{\gamma \gamma }} > $ 2000 GeV is selected in the analysis. The results of a likelihood fit to the background-only hypothesis are also shown. The shaded regions show the 1 and 2 standard deviation uncertainty bands associated with the fit, and reflect the statistical uncertainty of the data. The lower panels show the difference between the data and fit, divided by the statistical uncertainty in the data points. |

png pdf |
Figure 3:
The 95% CL upper limits on the production of diphoton resonances as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the analysis of the 12.9 fb$^{-1}$ data collected in 2016 at 13 TeV . The blue-grey (darker) curves and the green (lighter) ones correspond to the scalar and RS graviton signals, respectively. Solid (dashed) curves represent the observed (median expected) exclusion limit. The expected results are shown with their 1 standard deviation dispersion bands. The leading-order RS graviton production cross section is shown by the red dot-dashed curves. The results are shown for (upper) a narrow, (middle) an intermediate-width, and (lower) a broad resonance, with the value of the width ${\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} $, relative to the mass, indicated in the legend of each plot. |

png pdf |
Figure 4-a:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4 \times 10^{-4}$ (a), $1.4 \times 10^{-2} $ (b), and $5.6 \times 10^{-2} $ (c) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the analysis of the 12.9 fb$^{-1}$ data collected at ${\sqrt {s}} =$ 13 TeV in 2016. Solid black and dashed blue lines correspond to spin-0 and spin-2 resonances respectively. |

png pdf |
Figure 4-b:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4 \times 10^{-4}$ (a), $1.4 \times 10^{-2} $ (b), and $5.6 \times 10^{-2} $ (c) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the analysis of the 12.9 fb$^{-1}$ data collected at ${\sqrt {s}} =$ 13 TeV in 2016. Solid black and dashed blue lines correspond to spin-0 and spin-2 resonances respectively. |

png pdf |
Figure 4-c:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4 \times 10^{-4}$ (a), $1.4 \times 10^{-2} $ (b), and $5.6 \times 10^{-2} $ (c) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the analysis of the 12.9 fb$^{-1}$ data collected at ${\sqrt {s}} =$ 13 TeV in 2016. Solid black and dashed blue lines correspond to spin-0 and spin-2 resonances respectively. |

png pdf |
Figure 5:
The 95% CL upper limits on the production of diphoton resonances as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 13 TeV data collected in 2015 and in 2016. The blue-grey (darker) curves and the green (lighter) ones correspond to the scalar and RS graviton signals, respectively. Solid (dashed) curves represent the observed (median expected) exclusion limit. The expected results are shown with their 1 standard deviation dispersion bands. The leading-order RS graviton production cross section is shown by the red dot-dashed curves. The results are shown for (upper) a narrow, (middle) an intermediate-width, and (lower) a broad resonance, with the value of the width ${\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} $, relative to the mass, indicated in the legend of each plot. |

png pdf |
Figure 6-a:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4\times 10^{-4}$ (a,b) and $ 5.6\times 10^{-2} $ (c,d) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 13 TeV data recorded in 2015 and 2016. The results obtained with the two individual datasets are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a,c) and (b,d) respectively. |

png pdf |
Figure 6-b:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4\times 10^{-4}$ (a,b) and $ 5.6\times 10^{-2} $ (c,d) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 13 TeV data recorded in 2015 and 2016. The results obtained with the two individual datasets are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a,c) and (b,d) respectively. |

png pdf |
Figure 6-c:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4\times 10^{-4}$ (a,b) and $ 5.6\times 10^{-2} $ (c,d) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 13 TeV data recorded in 2015 and 2016. The results obtained with the two individual datasets are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a,c) and (b,d) respectively. |

png pdf |
Figure 6-d:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4\times 10^{-4}$ (a,b) and $ 5.6\times 10^{-2} $ (c,d) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 13 TeV data recorded in 2015 and 2016. The results obtained with the two individual datasets are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a,c) and (b,d) respectively. |

png pdf |
Figure 7:
The 95% CL upper limits on the production of diphoton resonances as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 8 and 13 TeV data. The 8 TeV results are scaled by the ratio of the 8 to 13 TeV cross sections. The blue-grey (darker) curves and the green (lighter) ones correspond to the scalar and RS graviton signals, respectively. Solid (dashed) curves represent the observed (median expected) exclusion limit. The expected results are shown with their 1 standard deviation dispersion bands. The leading-order RS graviton production cross section is shown by the red dot-dashed curves. The results are shown for (upper) a narrow, (middle) an intermediate-width, and (lower) a broad resonance, with the value of the width ${\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} $, relative to the mass, indicated in the legend of each plot. |

png pdf |
Figure 8-a:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4 \times 10^{-4} $ (a,b) and $ 5.6 \times 10^{-2} $ (c,d) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 8 and 13 TeV data. The results obtained at the two centre of mass energies are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a,c) and (b,d) columns respectively. |

png pdf |
Figure 8-b:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4 \times 10^{-4} $ (a,b) and $ 5.6 \times 10^{-2} $ (c,d) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 8 and 13 TeV data. The results obtained at the two centre of mass energies are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a,c) and (b,d) columns respectively. |

png pdf |
Figure 8-c:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4 \times 10^{-4} $ (a,b) and $ 5.6 \times 10^{-2} $ (c,d) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 8 and 13 TeV data. The results obtained at the two centre of mass energies are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a,c) and (b,d) columns respectively. |

png pdf |
Figure 8-d:
Observed background-only $p$-values for resonances with $ {\Gamma _{ {\mathrm {X}}} / m_{ {\mathrm {X}}}} = 1.4 \times 10^{-4} $ (a,b) and $ 5.6 \times 10^{-2} $ (c,d) as a function of the resonance mass ${m_{ {\mathrm {X}}}} $, from the combined analysis of the 8 and 13 TeV data. The results obtained at the two centre of mass energies are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a,c) and (b,d) columns respectively. |

Summary |

A search for the resonant production of high mass photon pairs has been presented. The analysis is based on 12.9 fb$^{-1}$ of pp collisions collected by the CMS experiment in 2016 at $\sqrt{s} =$ 13 TeV. Events containing two photon candidates with transverse momenta above 75 GeV are selected. The mass spectrum above 500 GeV is inspected to search for the production of spin-0 and spin-2 resonances. Limits on the production of scalar resonances and Randall-Sundrum gravitons in the range where 0.5 TeV $ < m_{\mathrm{X}} < $ 4.5 TeV and $\Gamma_{\mathrm{X}}/m_{\mathrm{X}} < 5.6 \times 10^{-2}$ are set using the modified frequentist approach. The results obtained with the 2016 dataset are combined statistically with those obtained in Ref. [12] using data corresponding to 19.7 fb$^{-1}$ and 3.3 fb$^{-1}$ recorded at $\sqrt{s}=$ 8 and $\sqrt{s}=$ 13 TeV respectively. No significant excess is observed above the predictions from the standard model. Using the LO cross sections from PYTHIA-8.2, RS gravitons with masses below 3.85 and 4.45 TeV are excluded for $\tilde{k} =$ 0.1 and 0.2 respectively. For $\tilde{k}=0.01$, graviton masses below 1.95 TeV are excluded, except for the region between 1.75 TeV and 1.85 TeV. These are, to-date, the most stringent limits on RS graviton production. |

Additional Figures | |

png pdf |
Additional Figure 1-a:
Photon identification efficiency for all selection requirements except the electron rejection, measured in barrel (a) and endcaps (b) using the tag-and-probe method for both data and simulated events. The lower panel shows the ratio between the efficiencies in data and simulation. |

png pdf |
Additional Figure 1-b:
Photon identification efficiency for all selection requirements except the electron rejection, measured in barrel (a) and endcaps (b) using the tag-and-probe method for both data and simulated events. The lower panel shows the ratio between the efficiencies in data and simulation. |

png pdf |
Additional Figure 2-a:
Observed background-only $p$-values for resonances with $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-2}$ as a function of the resonance mass $m_{\mathrm{X}}$, from the combined analysis of the 13 TeV data recorded in 2015 and 2016. The results obtained with the two individual datasets are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a) and (b) respectively. |

png pdf |
Additional Figure 2-b:
Observed background-only $p$-values for resonances with $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-2}$ as a function of the resonance mass $m_{\mathrm{X}}$, from the combined analysis of the 13 TeV data recorded in 2015 and 2016. The results obtained with the two individual datasets are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown in (a) and (b) respectively. |

png pdf |
Additional Figure 3-a:
Observed background-only $p$-values for resonances with $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-2}$ as a function of the resonance mass $m_{\mathrm{X}}$, from the combined analysis of the 8 and 13 TeV data. Results obtained at each of the two centre of mass energies are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown respectively in (a) and (b) respectively. |

png pdf |
Additional Figure 3-b:
Observed background-only $p$-values for resonances with $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-2}$ as a function of the resonance mass $m_{\mathrm{X}}$, from the combined analysis of the 8 and 13 TeV data. Results obtained at each of the two centre of mass energies are also shown. Curves corresponding to the scalar and RS graviton hypotheses are shown respectively in (a) and (b) respectively. |

png pdf |
Additional Figure 4:
Likelihood scan for the cross section of a narrow-width spin-0 resonance with a mass of 750 GeV. Results for the 8 TeV data (19.7 fb$^{-1}$), 13 TeV data recorded in 2015 (3.3 fb$^{-1}$) and in 2016 (12.9 fb$^{-1}$), and their combination are shown. |

png pdf |
Additional Figure 5-a:
Observed invariant mass spectra for the EBEB (a) and EBEE (b) in the region 510 $ < m_{\gamma \gamma } < $ 1030 GeV. The results of a likelihood fit to the background-only hypothesis are also shown. The shaded regions show the 1 and 2 standard deviation uncertainty bands associated with the fit, and reflect the statistical uncertainty of the data. The red curve shows the shape expected for a spin-0 signal corresponding to the largest excess observed in the combined analysis of 8 TeV and 2015 13 TeV data. The lower panels show the difference between the data and fit, divided by the statistical uncertainty in the data points. |

png pdf |
Additional Figure 5-b:
Observed invariant mass spectra for the EBEB (a) and EBEE (b) in the region 510 $ < m_{\gamma \gamma } < $ 1030 GeV. The results of a likelihood fit to the background-only hypothesis are also shown. The shaded regions show the 1 and 2 standard deviation uncertainty bands associated with the fit, and reflect the statistical uncertainty of the data. The red curve shows the shape expected for a spin-0 signal corresponding to the largest excess observed in the combined analysis of 8 TeV and 2015 13 TeV data. The lower panels show the difference between the data and fit, divided by the statistical uncertainty in the data points. |

png pdf |
Additional Figure 6-a:
Expected and observed 95% C.L. exclusion limits obtained with the 13 TeV 2016 data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2} $, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 6-b:
Expected and observed 95% C.L. exclusion limits obtained with the 13 TeV 2016 data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2} $, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 6-c:
Expected and observed 95% C.L. exclusion limits obtained with the 13 TeV 2016 data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2} $, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 6-d:
Expected and observed 95% C.L. exclusion limits obtained with the 13 TeV 2016 data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2} $, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 6-e:
Expected and observed 95% C.L. exclusion limits obtained with the 13 TeV 2016 data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2} $, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 6-f:
Expected and observed 95% C.L. exclusion limits obtained with the 13 TeV 2016 data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2} $, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 7-a:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 2015 and 2016 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 7-b:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 2015 and 2016 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 7-c:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 2015 and 2016 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 7-d:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 2015 and 2016 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 7-e:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 2015 and 2016 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 7-f:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 2015 and 2016 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $ \Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4} $, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 8-a:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 8 and 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4}$, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 8-b:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 8 and 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4}$, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 8-c:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 8 and 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4}$, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 8-d:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 8 and 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4}$, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 8-e:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 8 and 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4}$, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

png pdf |
Additional Figure 8-f:
Expected and observed 95% C.L. exclusion limits obtained with the combination of the 8 and 13 TeV data for different signal hypotheses. The range 0.5 $ < m_{\mathrm{X}} < $ 4.5 TeV is shown for $\Gamma _{\mathrm{X}} / m_{\mathrm{X}} = 1.4\times 10^{-4}$, $ 1.4\times 10^{-2}$, $ 5.6\times 10^{-2} $. Plots (a), (c), (e) and (b), (d), (f) corresponds to the scalar and RS graviton signals respectively. |

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Compact Muon Solenoid LHC, CERN |