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Heavy quark expansion parameters from lattice NRQCD

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 نشر من قبل Naoto Tsutsui
 تاريخ النشر 2003
  مجال البحث
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We present a lattice QCD calculation of the heavy quark expansion parameters $mu_{pi}^2$ and $mu_G^2$ for heavy-light mesons and heavy-light-light baryons. The calculation is carried out on a 20$^3times$48 lattice at $beta$ = 6.0 in the quenched approximation, using the lattice NRQCD action for heavy quarks. We obtain the parameters $mu_{pi}^2$ and $mu_G^2$ in two different methods: a direct calculation of the matrix elements and an indirect calculation through the mass spectrum, and confirm that the both methods give consistent results. We also discuss an application to the lifetime ratios.



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