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Review of Charm Lifetimes

Harry W. K. Cheung
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Abstract

A review of the latest experimental results on charm particle lifetimes is presented. The most significant update is that the D_s^+ lifetime is conclusively larger than the D^0 lifetime and signifies that W-exchange/W-annihilation contributions are large. Using new high statistics data on $D^+\to K^+π^+π^-$ together with the D_s^+ lifetime and some assumptions, one can phenomenologically extract the strength of the W-exchange contribution in D^0 decays and of W-annihilation in D_s^+ decays. These are larger than or at the limit of theoretical expectations using QCD-based operator production expansion techniques.

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Harry W. K. Cheung. 1999-12-10. Review of Charm Lifetimes. https://arxiv.org/abs/hep-ex/9912021

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