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arXiv · hep-ph/9507391

Charm lifetime

Sandra Malvezzi
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Abstract

A review of the charmed meson and baryon lifetimes is presented. Our knowledge of charmed particle lifetimes has greatly improved over the past two years, a crucial rôle having been played by the E687 experiment at Fermilab, which has almost quadrupled the samples of $D$ mesons. The lifetime ratios $τ(D^+)/τ(D^0)$ and $τ(D_s^+)/τ(D^0)$ are now known with an accuracy of 1.7\% and 3.7\% respectively. In the baryon sector the statistics is still limited, but the experimental results on $Λ_c^+$, $Ξ_c^0$ and $Ξ_c^+$ exhibit a clear pattern of lifetime hierarchy, as expected from simple theoretical arguments. The first measurement of $τ(Ω_c^0)$ from E687 is also presented to complete the charmed baryon lifetime picture. The more accurate experimental scenario can provide information on non-perturbative QCD effects and the hadronic matrix elements.

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Sandra Malvezzi. 1995-07-24. Charm lifetime. https://doi.org/10.1007/bf02731706

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