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Study of $psi(2S)$ production and cold nuclear matter effects in pPb collisions at $sqrt{s_{NN}}=5~mathrm{TeV}$

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 نشر من قبل Zhenwei Yang
 تاريخ النشر 2016
  مجال البحث
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The production of $psi(2S)$ mesons is studied in dimuon final states using proton-lead collision data collected by the LHCb detector. The data sample corresponds to an integrated luminosity of $1.6~mathrm{nb}^{-1}$. The nucleon-nucleon centre-of-mass energy of the proton-lead collisions is $sqrt{s_{NN}}=5~mathrm{TeV}$. The measurement is performed using $psi(2S)$ mesons with transverse momentum less than $14~mathrm{GeV}/c$ and rapidity $y$ in the ranges $1.5<y<4.0$ and $-5.0<y<-2.5$ in the nucleon-nucleon centre-of-mass system. The forward-backward production ratio and the nuclear modification factor are determined for $psi(2S)$ mesons. Using the production cross-section results of $psi(2S)$ and $J/psi$ mesons from $b$-hadron decays, the $bbar{b}$ cross-section in pPb collisions at $sqrt{s_{NN}}=5~mathrm{TeV}$ is obtained.



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