اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of the Ds+ - Ds- production asymmetry in 7 TeV pp collisions
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Heavy quark production in 7 TeV centre-of-mass energy pp collisions at the LHC is not necessarily flavour symmetric. The production asymmetry, A_P, between Ds+ and Ds- mesons is studied using the phipi(+/-) decay mode in a data sample of 1.0/fb collected with the LHCb detector. The difference between pi+ and pi- detection efficiencies is determined using the ratios of fully reconstructed to partially reconstructed D*(+/-) decays. The overall production asymmetry in the Ds rapidity region 2.0 to 4.5 with transverse momentum larger than 2 GeV is measured to be A_P=(-0.33 +/- 0.22 +/- 0.10)%. This result can constrain models of heavy flavour production.
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The asymmetry in the production cross-section sigma of D+/- mesons, A_P = (sigma(D+) - sigma(D-))/(sigma(D+) + sigma(D-)), is measured in bins of pseudorapidity eta and transverse momentum p_T within the acceptance of the LHCb detector. The result is
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