A measurement of the underlying event (UE) activity in proton-proton collisions is performed using events with charged-particle jets produced in the central pseudorapidity region ($|\eta|^\text{jet} < 2$) and with transverse momentum $1 \leq p_T^\text{jet} < 100$ \text{GeV}. The analysis uses a data sample collected at a centre-of-mass energy of 2.76 \text{TeV} with the CMS experiment at the LHC. The UE activity is measured as a function of $p_T^\text{jet}$ in terms of the average multiplicity and scalar sum of transverse momenta of charged particles, with $|\eta| < 2$ and $p_T > 0.5$ \text{GeV}, in the azimuthal region transverse to the highest-$p_T$ jet direction. By further dividing the transverse region into two regions of smaller and larger activity, various components of the UE activity are separated.
Generated at Thursday, 12. December 2019 02:35PM