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arXiv · hep-ph/9908455

Reducing model dependence of spectator effects in inclusive decays of heavy baryons

M. B. Voloshin
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Abstract

The dependence of inclusive weak decay rates of heavy hadrons on light spectator quarks is considered. The analysis of a previous work on relating the effects in b baryons to those in charmed baryons is extended to explicit evaluation of the matrix elements of certain four-quark operators over heavy baryons. It is shown that the usually postulated color antisymmetry of these matrix elements is significantly broken. The flavor-singlet shift of inclusive decay rates of b baryons due to the spectator effects is shown to be strongly suppressed in the leading-log approximation. Combined with the results for the flavor non-singlet splittings, this observation allows to argue, in a less model-dependent way, than before, that within the present understanding of the spectator effects it is highly unlikely that the lifetimes of the Lambda_b and the B_d can be split by more than 10%.

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M. B. Voloshin. 1999-08-24. Reducing model dependence of spectator effects in inclusive decays of heavy baryons. https://doi.org/10.1103/physrevd.61.074026

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