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Effect of flavor-dependent partonic transverse momentum on the determination of the $W$ boson mass in hadronic collisions

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 نشر من قبل Marco Radici
 تاريخ النشر 2018
  مجال البحث
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Within the framework of transverse-momentum-dependent factorization, we investigate for the first time the impact of a flavor-dependent intrinsic transverse momentum of quarks on the production of $W^{pm}$ bosons in proton-proton collisions at $sqrt{s}$ = 7 TeV. We estimate the shift in the extracted value of the $W$ boson mass $M_W$ induced by different choices of flavor-dependent parameters for the intrinsic quark transverse momentum by means of a template fit to the transverse-mass and the lepton transverse-momentum distributions of the $W$-decay products. We obtain $-6leq Delta M_{W^+} leq 9$ MeV and $-4leq Delta M_{W^-} leq 3$ MeV with a statistical uncertainty of $pm 2.5$ MeV. Our findings call for more detailed investigations of flavor-dependent nonperturbative effects linked to the proton structure at hadron colliders.



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