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Ultrasoft contribution to heavy-quark pair production near threshold

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 نشر من قبل Martin Beneke
 تاريخ النشر 2008
  مجال البحث
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 تأليف M. Beneke




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We compute the third-order correction to the heavy-quark current correlation function due to the emission and absorption of an ultrasoft gluon. Our result supplies a missing contribution to top-quark pair production near threshold and the determination of the bottom quark mass from QCD sum rules.



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