We present the first measurement of the D*+ width using 9/fb of e+e− data collected near the γ(4S) resonance by the CLEO II.V detector. Our method uses advanced tracking techniques and a reconstruction method that takes advantage of the small vertical size of the Cornell Electron-positron Storage Ring beam spot to measure the energy release distribution from the D*+ → D0π+ decay. We find Γ(D*+) = 96 ±4(stat) ± 22(syst)keV. We also measure the energy release in the decay and compute Δm = mD*+ − mD0 = 145.412 ± 0.002(stat) ± 0.012(syst)MeV/c2.

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Persistent URL dx.doi.org/10.1103/PhysRevLett.87.251801
Journal Physical Review Letters
Ahmed, S. (S.), Alam, M.S. (M. S.), Athar, S.B. (S. B.), Jian, L. (L.), Ling, L. (L.), Saleem, M. (M.), … Urheim, J. (J.). (2001). First measurement of Γ(D*+). Physical Review Letters, 87(25), 251801‐1–251801‐5. doi:10.1103/PhysRevLett.87.251801