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Light anti-nuclei production in pp collisions at $sqrt{s}$=7 and 14 TeV

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 نشر من قبل Yuliang Yan
 تاريخ النشر 2011
  مجال البحث
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A dynamically constrained coalescence model based on the phase space quantization and classical limit method was proposed to investigate the production of light nuclei (anti-nuclei) in non-single diffractive (NSD) pp collisions at $sqrt{s}$=7 and 14 TeV. This calculation was based on the final hadronic state in the PYTHIA and PACIAE model simulations, the event sample consisted of 1.2$times 10^8$ events in both simulations. The PACIAE model calculated $bar D$ yield of 6.247$times 10^{-5}$ in NSD pp collisions at $sqrt{s}$=7 TeV is well comparing with the ALICE rough datum of 5.456$times 10^{-5}$. It indicated the reliability of proposed method in some extent. The yield, transverse momentum distribution, and rapidity distribution of the $bar D$, $^3{bar{He}}$, and $_{barLambda} ^3{bar H}$ in NSD pp collisions at $sqrt{s} $=7 and 14 TeV were predicted by PACIAE and PYTHIA model simulations. The yield resulted from PACIAE model simulations is larger than the one from PYTHIA model. This might reflect the role played by the parton and hadron rescatterings.



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