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Quenching of jets tagged with $W$ bosons in high-energy nuclear collisions

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 نشر من قبل Shan-Liang Zhang
 تاريخ النشر 2021
  مجال البحث
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We carry out the first detailed calculations of jet production associated with $W$ gauge bosons in Pb+Pb collisions at the Large Hadron Collider (LHC). In our calculations, the production of $W$+jet in p+p collisions as a reference is obtained by Sherpa, which performs next-to-leading-order matrix element calculations matched to the resummation of parton shower simulations, while jet propagation and medium response in the quark-gluon plasma are simulated with the Linear Boltzmann Transport (LBT) model. We provide numerical predictions on seven observables of $W$+jet production with jet quenching in Pb+Pb collisions: the medium modification factor for the tagged jet cross sections $I_{AA}$, the distribution in invariant mass between the two leading jets in $N_{jets}ge 2$ events $m_{jj}$, the missing $p_T$ or the vector sum of the lepton and jet transverse momentum $|vec{p}_T^{Miss}|$, the summed scalar $p_T$ of all the jets in an event $S_T$, transverse momentum imbalance $x_{jW}$, average number of jets per $W$ boson $R_{jW}$, and azimuthal angle between the $W$ boson and jets $Delta phi_{jW}$. The distinct nuclear modifications of these seven observables in Pb+Pb relative to that in p+p collisions are presented with detailed discussions.



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