Measurement of normalized differential $t\bar{t}$ cross sections in the dilepton channel from pp collisions at 13 TeV

Measurements of normalized differential cross sections for top quark pair production are performed in the dilepton decay channels in proton-proton collisions at a center-of-mass energy of 13~TeV. The differential cross sections are measured with data corresponding to an integrated luminosity of 2.1~fb$^{-1}$ recorded by the CMS experiment at the LHC. We have measured the cross sections differentially as a function of the kinematic properties of the leptons (electron or muon), jets from bottom quark hadronization, top quarks, and top quark pairs at the particle and parton levels. The $t\bar{t}$ differential cross section measurements are compared to several Monte Carlo generators that implement calculations up to next-to-leading order in perturbative quantum chromodynamics interfaced with parton showering, and also to fixed-order theoretical calculations of top quark pair production beyond next-to-leading order accuracy.