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Renormalization and factorization scale analysis of $bar{b}b$ production in antiproton-proton collisions

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 نشر من قبل Jiri Chyla
 تاريخ النشر 2003
  مجال البحث
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 تأليف Jiri Chyla




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There a sizable and systematic discrepancy between experimental data on the $bar{b}b$ production in $bar{mathrm p}$p, $gamma$p and $gammagamma$ collisions and existing theoretical calculations within perturbative QCD. Before interpreting this discrepancy as a signal of new physics, it is important to understand quantitatively the ambiguities of conventional calculations. In this paper the uncertainty coming from renormalization and factorization scale dependence of finite order perturbation calculations of the total cross section of $bar{b}b$ production in $bar{mathrm{p}}$p collisions is discussed in detail. It is shown that the mentioned discrepancy is reduced significantly if these scales are fixed via the Principle of Minimal Sensitivity.



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