Differential top quark pair production cross sections are measured in the dilepton final states e$^+$e$^-$, $μ^+μ^-$, and e$^\pmμ^\mp$, as a function of kinematic variables of the two-neutrino system: the transverse momentum $p_\mathrm{T}^{νν}$ of the dineutrino system, the minimum distance in azimuthal angle between $\vec{p}_\mathrm{T}^{\,νν}$ and leptons, and in two dimensions in bins of both observables. The measurements are performed using CERN LHC proton-proton collisions at $\sqrt{s}$ = 13 TeV, recorded by the CMS detector between 2016 and 2018, corresponding to an integrated luminosity of 138 fb$^{-1}$. The measured cross sections are unfolded to the particle level using an unregularized least squares method. Results are compared with predictions by the standard model of particle physics, and found to be in agreement with theoretical calculations as well as Monte Carlo simulations.
Data and MC simulation yields after the event selection, combined for all data-taking periods and split by channels. The uncertainties on the expected yields include systematic and statistical uncertainties. The relative contribution in percent of each process to the total expected yield of a channel is given in parentheses.
Observed (black markers) and expected distributions of leading lepton $p_{T}$ after event selection. The hatched (grey) areas denote the systematic (total) uncertainties in the expected yields. Events from all data-taking periods and all channels are combined. The lower panel of each plot shows the ratio between observed and expected distributions. The last bin includes all events above the plotted range. The entry Background corresponds to the sum of all the SM predictions.
Observed (black markers) and expected distributions of leading jet $p_{T}$ after event selection. The hatched (grey) areas denote the systematic (total) uncertainties in the expected yields. Events from all data-taking periods and all channels are combined. The lower panel of each plot shows the ratio between observed and expected distributions. The last bin includes all events above the plotted range. The entry Background corresponds to the sum of all the SM predictions.
The results of a search for stealth supersymmetry in final states with two photons and jets, targeting a phase space region with low missing transverse momentum ($p_\text{T}^\text{miss}$), are reported. The study is based on a sample of proton-proton collisions at $\sqrt{s}$ = 13 TeV collected by the CMS experiment, corresponding to an integrated luminosity of 138 fb$^{-1}$. As LHC results continue to constrain the parameter space of the minimal supersymmetric standard model, the low $p_\text{T}^\text{miss}$ regime is increasingly valuable to explore. To estimate the backgrounds due to standard model processes in such events, we apply corrections derived from simulation to an estimate based on a control selection in data. The results are interpreted in the context of simplified stealth supersymmetry models with gluino and squark pair production. The observed data are consistent with the standard model predictions, and gluino (squark) masses of up to 2150 (1850) GeV are excluded at the 95% confidence level.
Best fit values of the two parameters $A$ and $m$ of the linear 2-to-4-jets-bin adjustment in the background Monte Carlo. Please see the text of the paper for an explanation of $A$ and $m$. Uncertainties on $A$ and $m$ can be obtained from the covariance matrix of the fit, available as a separate table in this HEPData Record.
Covariance matrix of the two parameters $A$ and $m$ of the linear 2-to-4-jets-bin adjustment in the background Monte Carlo. Please see the text of the paper for an explanation of $A$ and $m$. Best fit values of $A$ and m are available as a separate table in this HEPData record.
Best fit values of the two parameters $A$ and $m$ of the linear 2-to-5-jets-bin adjustment in the background Monte Carlo. Please see the text of the paper for an explanation of $A$ and $m$. Uncertainties on $A$ and $m$ can be obtained from the covariance matrix of the fit, available as a separate table in this HEPData Record.