Using a sample of tagged Ds+ decays collected near the Ds*±Ds peak production energy in e+e- collisions with the CLEO-c detector, we study the leptonic decay Ds+→τ+ντ via the decay channel τ+→e+νeν̄τ. We measure B(Ds+→τ+ντ)=(6. 17±0.71±0.34)%, where the first error is statistical and the second systematic. Combining this result with our measurements of Ds+→μ+νμ and Ds+→τ+ντ (via τ+→π+ν ̄τ), we determine fDs=(274±10±5)MeV.
ASJC Scopus subject areas
- Physics and Astronomy(all)