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تسجيل مستخدم جديدHeavy quark expansion parameters from lattice NRQCD
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Using the lattice NRQCD action for heavy quark, we calculate the heavy quark expansion parameters $mu_{pi}^2$ and $mu_G^2$ for heavy-light mesons and heavy-light-light baryons. The results are compared with the mass differences among heavy hadrons to test the validity of HQET relations on the lattice.
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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 appr
oximation, 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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