Search for dark matter produced in association with b-jets in proton-proton collisions at $\sqrt{\text{s}}=13$ TeV with the CMS detector using full Run2 data

A search for dark matter particles in the events containing large missing transverse energy accompanied by b-quarks has been performed. The data collected by the Compact Muon Solenoid detector at the Large Hadron Collider in the years 2016, 2017 and 2018 in proton-proton collisions at a centre-of-mass energy of $\sqrt{\text{s}}=13$ TeV, which correspond to 138fb$^{−1}$ integrated luminosity has been analyzed in the present study. For the analysis, two signal categories have been defined to account for the effects of detector acceptance and b-tagging identification. To model the background four control regions have been designed for each signal category. The signal is extracted using binned profile likelihood fit while treating the systematic uncertainties as nuisance parameters in the fit. The interpretation has been carried out in terms of dark matter production to constrain the parameter space of two Higgs doublet model with an additional light pseudo-scalar (2HDM+a).