Measurement of associated Z + charm production in proton-proton collisions at

A study of the associated production of a $$ boson and a charm quark jet ( $$ ), and a comparison to production with a $$ quark jet ( $$ ), in $$ collisions at a centre-of-mass energy of 8 $$ are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 $$ , collected with the CMS detector at the CERN LHC. The $$ boson candidates are identified through their decays into pairs of electrons or muons. Jets originating from heavy flavour quarks are identified using semileptonic decays of $$ or $$ flavoured hadrons and hadronic decays of charm hadrons. The measurements are performed in the kinematic region with two leptons with $$ , $$ , $$ , and heavy flavour jets with $$ and $$ . The $$ production cross section is measured to be $$ . The ratio of the $$ and $$ production cross sections is measured to be $$ . The $$ production cross section and the cross section ratio are also measured as a function of the transverse momentum of the $$ boson and of the heavy flavour jet. The measurements are compared with theoretical predictions.