Measurement of B(D_s+ -> mu+ nu_mu)/B(D_s+ -> phi mu+ nu_mu) and Determination of the Decay Constant f_{D_s}

Kodama, K.; Torikai, S.; Ushida, N.; Mokhtarani, A.; Paolone, V. S.; Volk, J. T.; Wilcox, J. O.; Yager, P. M.; Edelstein, R. M.; Freyberger, A. P.; Gibaut, D. B.; Lipton, R. J.; Nichols, W. R.; Potter, D. M.; Russ, J. S.; Zhang, C.; Zhang, Y.; Jang, H. I.; Kim, J. Y.; Baller, B. R.; Stefanski, R. J.; Nakazawa, K.; Chung, S. H.; Park, M. S.; Park, I. G.; Song, J. S.; Yoon, C. S.; Aryal, M.; Reay, N. W.; Sidwell, R. A.; Stanton, N. R.; Yoshida, S.; Chikawa, M.; Hara, T.; Aoki, S.; Hoshino, K.; Kobayashi, M.; Komatsu, M.; Miyanishi, M.; Nakamura, M.; Nakanishi, S.; Niwa, K.; Nomura, M.; Okada, K.; Tajima, H.; Teraoka, K.; Dunlea, J. M.; Frederiksen, S. G.; Kuramata, S.; Lundberg, B. G.; Oleynik, G. A.; Reibel, K.; Kalbfleisch, G. R.; Skubic, P.; Snow, J. M.; Willis, S. E.; Nakamura, K.; Okusawa, T.; Yoshida, T.; Okabe, H.; Yokota, J.; Ihara, N.; Kazuno, M.; Koya, T.; Niu, E.; Ogawa, S.; Shibuya, H.; Watanabe, S.; Yasuda, N.; Ehara, K.; Horie, K.; Sato, Y.; Suzuki, K.; Tezuka, I.

Measurement of B(D_s+ -> mu+ nu_mu)/B(D_s+ -> phi mu+ nu_mu) and Determination of the Decay Constant f_{D_s}

Authors

Description

We have observed $23.2 \pm 6.0_{-0.9}^{+1.0}$ purely-leptonic decays of $D_s^+ -> μ^+ ν_μ$ from a sample of muonic one prong decay events detected in the emulsion target of Fermilab experiment E653. Using the $D_s^+ -> ϕμ^+ ν_μ$ yield measured previously in this experiment, we obtain $B(D_s^+ --> μ^+ ν_μ) / B(D_s^+ --> ϕμ^+ ν_μ) =0.16 \pm 0.06 \pm 0.03$. In addition, we extract the decay constant $f_{D_s}=194 \pm 35 \pm 20 \pm 14 MeV$.
15 pages including one figure