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Implications of Isospin Conservation in $Λ_b$ Decays and Lifetime

Alakabha Datta·Harry J. Lipkin·Patrick. J. O'Donnell
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Abstract

We consider isospin predictions for the semi-leptonic and non-leptonic decays of the $Λ_b$ baryon. Isospin conservation of the strong interactions constrains the possible final states in $Λ_b$ decays. Since the baryon hyperfine splittings depend upon light quark dynamics and do not decrease with increasing heavy quark mass, this leads in general to to phase space enhancements in $Λ_b$ decays relative to $B$ meson decays for the same underlying quark transitions. Consequently the $Λ_b$ lifetime is smaller than the $B$ lifetime. Phase space enhancements in $Λ_b$ decays relative to $B$ decays can be understood in terms of hyperfine interactions in the heavy quark system.

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Alakabha Datta, Harry J. Lipkin, Patrick. J. O'Donnell. 1999-01-29. Implications of Isospin Conservation in $Λ_b$ Decays and Lifetime. https://doi.org/10.1016/s0370-2693(99)00139-2

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