Non-perturbative effects in semi-leptonic Bc decays

نویسندگان

  • Thomas Mannel
  • Stefan Wolf
چکیده

We discuss the impact of the soft degrees of freedom inside the Bc meson on its rate in the semi-leptonic decay Bc → X`ν̄` where X denotes light hadrons below the D0 threshold. In particular we identify contributions involving soft hadrons which are non-vanishing in the limit of massless leptons. These contributions become relevant for a measurement of the purely leptonic Bc decay rate, which due to helicity suppression involves a factor m` and thus is much smaller than the contributions involving soft hadrons. PACS Nos.: 11.10.St, 12.39.Hg, 12.39.Jh, 13.20.Gd

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تاریخ انتشار 2008