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NRQCD Factorization and Velocity-dependence of NNLO Poles in Heavy Quarkonium Production

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 نشر من قبل Gouranga Nayak
 تاريخ النشر 2006
  مجال البحث
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 تأليف Gouranga C. Nayak




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We study the transition of a heavy quark pair from octet to singlet color configurations at next-to-next-to-leading order (NNLO) in heavy quarkonium production. We show that the infrared singularities in this process are consistent with NRQCD factorization to all orders in the heavy quark relative velocity v. This factorization requires the gauge-completed matrix elements that we introduced previously to prove NNLO factorization to order v ^2.

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