Speaker
Description
The double differential cross sections of the Drell--Yan lepton pair ($\ell^+\ell^-$, dielectron or dimuon) production, as functions the invariant mass $m_{\ell\ell}$, transverse momentum $p_\mathrm{T}(\ell\ell)$, and
$\varphi^*$, are measured. The $\varphi^*$ observable is highly correlated with
$p_\mathrm{T}(\ell\ell)$ and is used to probe the low-$p_\mathrm{T}(\ell\ell)$
region in a complementary way. Dilepton masses up to 1\TeV are investigated. Additionally, a measurement is performed requiring at least one jet in the final state. To benefit from partial cancellation of the systematic uncertainty, the ratios of the differential cross sections in $p_\mathrm{T}(\ell\ell)$ and $\varphi^*$ for different $m_{\ell\ell}$ ranges over the ones in the \PZ mass peak interval are presented. The collected data correspond to an integrated luminosity of $36.3\,\text{fb}^{-1}$ of proton--proton collisions recorded with the CMS detector at the LHC at a center-of-mass energy of 13\TeV in 2016. Measurements are compared to state-of-the-art predictions based on perturbative quantum chromodynamics, including soft-gluon resummation.
