CMS-PAS-FTR-18-040

CMS-PAS-FTR-18-040
Search for a new scalar resonance decaying to a pair of Z bosons at the High-Luminosity LHC
CMS Collaboration
February 2019

Abstract: For a heavy resonance decaying into a pair of Z bosons, a projection of current CMS searches to the HL-LHC is presented. The study considers pp collisions for an integrated luminosity of 3000 fb$^{-1}$ and takes into account the Phase-2 upgrade of the CMS detector. The final state with two leptons and two quarks is used to search for heavy resonances in the mass range from 550 GeV to 3 TeV. The scalar particle X is assumed to have a decay width much narrower than the detector resolution. Upper limits on the cross sections for models predicting the production of this scalar resonance through gluon fusion and electroweak mechanisms are presented.
Links: CDS record (PDF) ; inSPIRE record ; CADI line (restricted) ;

Figures & Tables	Summary	References	CMS Publications

Figures
png pdf	Figure 1: Distributions of the invariant mass $m_{{\mathrm {Z}} {\mathrm {Z}}}$ in the signal region expected at 3000 fb$^{-1}$, for the merged (left) and resolved (right) case in the different categories. The stacked histograms are the expected backgrounds from simulation. The blue points refer to the sum of background estimates derived from control samples. Examples of a 900 GeV ggF signal and a 1500 GeV VBF signal are given. The cross section corresponds to 10 times the excluded limit.
png pdf	Figure 1-a: Distributions of the invariant mass $m_{{\mathrm {Z}} {\mathrm {Z}}}$ in the signal region expected at 3000 fb$^{-1}$, for the merged (left) and resolved (right) case in the different categories. The stacked histograms are the expected backgrounds from simulation. The blue points refer to the sum of background estimates derived from control samples. Examples of a 900 GeV ggF signal and a 1500 GeV VBF signal are given. The cross section corresponds to 10 times the excluded limit.
png pdf	Figure 1-b: Distributions of the invariant mass $m_{{\mathrm {Z}} {\mathrm {Z}}}$ in the signal region expected at 3000 fb$^{-1}$, for the merged (left) and resolved (right) case in the different categories. The stacked histograms are the expected backgrounds from simulation. The blue points refer to the sum of background estimates derived from control samples. Examples of a 900 GeV ggF signal and a 1500 GeV VBF signal are given. The cross section corresponds to 10 times the excluded limit.
png pdf	Figure 1-c: Distributions of the invariant mass $m_{{\mathrm {Z}} {\mathrm {Z}}}$ in the signal region expected at 3000 fb$^{-1}$, for the merged (left) and resolved (right) case in the different categories. The stacked histograms are the expected backgrounds from simulation. The blue points refer to the sum of background estimates derived from control samples. Examples of a 900 GeV ggF signal and a 1500 GeV VBF signal are given. The cross section corresponds to 10 times the excluded limit.
png pdf	Figure 1-d: Distributions of the invariant mass $m_{{\mathrm {Z}} {\mathrm {Z}}}$ in the signal region expected at 3000 fb$^{-1}$, for the merged (left) and resolved (right) case in the different categories. The stacked histograms are the expected backgrounds from simulation. The blue points refer to the sum of background estimates derived from control samples. Examples of a 900 GeV ggF signal and a 1500 GeV VBF signal are given. The cross section corresponds to 10 times the excluded limit.
png pdf	Figure 1-e: Distributions of the invariant mass $m_{{\mathrm {Z}} {\mathrm {Z}}}$ in the signal region expected at 3000 fb$^{-1}$, for the merged (left) and resolved (right) case in the different categories. The stacked histograms are the expected backgrounds from simulation. The blue points refer to the sum of background estimates derived from control samples. Examples of a 900 GeV ggF signal and a 1500 GeV VBF signal are given. The cross section corresponds to 10 times the excluded limit.
png pdf	Figure 1-f: Distributions of the invariant mass $m_{{\mathrm {Z}} {\mathrm {Z}}}$ in the signal region expected at 3000 fb$^{-1}$, for the merged (left) and resolved (right) case in the different categories. The stacked histograms are the expected backgrounds from simulation. The blue points refer to the sum of background estimates derived from control samples. Examples of a 900 GeV ggF signal and a 1500 GeV VBF signal are given. The cross section corresponds to 10 times the excluded limit.
png pdf	Figure 2: Expected 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 $m_ {\mathrm {X}}$, with $f_{\mathrm {VBF}}$ as a free parameter (left) and fixed to 1 (right). Scenario 1 (top) and scenario 2 (bottom) are shown. The scalar particle X is assumed to have a narrower decay width than the detector resolution. The results are shown for the 2$\ell $2$ {\mathrm {q}}$ channel.
png pdf	Figure 2-a: Expected 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 $m_ {\mathrm {X}}$, with $f_{\mathrm {VBF}}$ as a free parameter (left) and fixed to 1 (right). Scenario 1 (top) and scenario 2 (bottom) are shown. The scalar particle X is assumed to have a narrower decay width than the detector resolution. The results are shown for the 2$\ell $2$ {\mathrm {q}}$ channel.
png pdf	Figure 2-b: Expected 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 $m_ {\mathrm {X}}$, with $f_{\mathrm {VBF}}$ as a free parameter (left) and fixed to 1 (right). Scenario 1 (top) and scenario 2 (bottom) are shown. The scalar particle X is assumed to have a narrower decay width than the detector resolution. The results are shown for the 2$\ell $2$ {\mathrm {q}}$ channel.
png pdf	Figure 2-c: Expected 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 $m_ {\mathrm {X}}$, with $f_{\mathrm {VBF}}$ as a free parameter (left) and fixed to 1 (right). Scenario 1 (top) and scenario 2 (bottom) are shown. The scalar particle X is assumed to have a narrower decay width than the detector resolution. The results are shown for the 2$\ell $2$ {\mathrm {q}}$ channel.
png pdf	Figure 2-d: Expected 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 $m_ {\mathrm {X}}$, with $f_{\mathrm {VBF}}$ as a free parameter (left) and fixed to 1 (right). Scenario 1 (top) and scenario 2 (bottom) are shown. The scalar particle X is assumed to have a narrower decay width than the detector resolution. The results are shown for the 2$\ell $2$ {\mathrm {q}}$ channel.

Tables
png pdf	Table 1: The sources of systematic uncertainty where minimum values are applied in ''YR18 systematics uncertainties'' scenario. Systematic uncertainties of the reference Run 2 analysis are described in Ref. [19].

Summary

References
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