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Leptonic decays of the Ds meson

ALEPH Collaboration
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Abstract

The purely leptonic decays Ds -> tau nu and Ds -> mu nu are studied in a sample of four million hadronic Z decays collected with the ALEPH detector at the LEP e+e- collider from 1991 to 1995. The branching fractions are extracted from a combination of two analyses, one optimized to select Ds -> tau nu decays with tau -> e nu nubar or mu nu nubar, and the other optimized for Ds-> mu nu decays. The results are used to evaluate the Ds decay constant, within the Standard Model: fDs = [285 +- 19(stat) +- 40 (syst)] MeV

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ALEPH Collaboration. 2002-01-15. Leptonic decays of the Ds meson. https://doi.org/10.1016/s0370-2693(02)01212-1

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