Search for supersymmetry in pp collisions at sqrt(s) = 13 TeV in the single-lepton final state using the sum of masses of large-radius jets

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 08 (2016) 122, 2016.
Inspire Record 1459054 DOI 10.17182/hepdata.77195

Results are reported from a search for supersymmetric particles in proton-proton collisions in the final state with a single, high transverse momentum lepton; multiple jets, including at least one b-tagged jet; and large missing transverse momentum. The data sample corresponds to an integrated luminosity of 2.3 inverse femtobarns at sqrt(s) = 13 TeV, recorded by the CMS experiment at the LHC. The search focuses on processes leading to high jet multiplicities, such as gluino pair production with gluinos to t t-bar neutralino[1]. The quantity M[J], defined as the sum of the masses of the large-radius jets in the event, is used in conjunction with other kinematic variables to provide discrimination between signal and background and as a key part of the background estimation method. The observed event yields in the signal regions in data are consistent with those expected for standard model backgrounds, estimated from control regions in data. Exclusion limits are obtained for a simplified model corresponding to gluino pair production with three-body decays into top quarks and neutralinos. Gluinos with a mass below 1600 GeV are excluded at a 95% confidence level for scenarios with low neutralino[1] mass, and neutralinos with a mass below 800 GeV are excluded for a gluino mass of about 1300 GeV. For models with two-body gluino decays producing on-shell top squarks, the excluded region is only weakly sensitive to the top squark mass.

12 data tables

Event yields obtained from simulated event samples, as the event selection criteria are applied. The category Other includes Drell-Yan, $t\bar{t}H(\rightarrow b\bar{b})$, $t\bar{t}t\bar{t}$, $WZ$, and $WW$. The yields for $t\bar{t}$ events in fully hadronic final states are included in the QCD multijet category. The category $t\bar{t}{\rm V}$ includes $t\bar{t}W$, $t\bar{t}Z$, and $t\bar{t}\gamma$. The benchmark signal models, T1tttt(NC) and T1tttt(C), are described in Section 3. The event selection requirements listed above the horizontal line in the middle of the table are defined as the baseline selection. The background estimates before the $H_{T}$ requirement are not specified because some of the simulated event samples do not extend to the low $H_{T}$ region. Given the size of the MC samples described in Section 3, rows with zero yield have statistical uncertainties of at most 0.16 events, and below 0.05 events in most cases.

Observed and predicted event yields for the signal regions (R4) and background regions (R1--R3) in data (2.3 $\textrm{fb}^{-1}$) in 200<MET<400 GeV region. Expected yields for the two SUSY T1tttt benchmark scenarios are also given. The results from two types of fits are reported: the predictive fit (PF) and the version of the global fit (GF) performed under the assumption of the null hypothesis ($r=0$). The predictive fit uses the observed yields in regions R1, R2, and R3 only and is effectively just a propagation of uncertainties. The global fit uses all four regions. The values of $\kappa$ obtained from the simulation fit are also listed. The first uncertainty in $\kappa$ is statistical, while the second corresponds to the total systematic uncertainty.

Observed and predicted event yields for the signal regions (R4) and background regions (R1--R3) in data (2.3 $\textrm{fb}^{-1}$) in MET>400 GeV region. Expected yields for the two SUSY T1tttt benchmark scenarios are also given. The results from two types of fits are reported: the predictive fit (PF) and the version of the global fit (GF) performed under the assumption of the null hypothesis ($r=0$). The predictive fit uses the observed yields in regions R1, R2, and R3 only and is effectively just a propagation of uncertainties. The global fit uses all four regions. The values of $\kappa$ obtained from the simulation fit are also listed. The first uncertainty in $\kappa$ is statistical, while the second corresponds to the total systematic uncertainty.

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