Observation of Bs0→Ds(*)+Ds(*)- using e⊃+e⊃- collisions and a determination of the Bs-B̄s width difference ΔΓs

S. Esen, A. J. Schwartz, I. Adachi, H. Aihara, K. Arinstein, V. Aulchenko, T. Aushev, T. Aziz, A. M. Bakich, V. Balagura, E. Barberio, A. Bay, M. Bischofberger, A. Bondar, A. Bozek, M. Bračko, T. E. Browder, M. C. Chang, P. Chang, A. ChenP. Chen, B. G. Cheon, C. C. Chiang, Y. Choi, J. Dalseno, M. Dash, Z. Doležl, Z. Drásal, A. Drutskoy, S. Eidelman, P. Goldenzweig, B. Golob, H. Ha, J. Haba, T. Hara, K. Hayasaka, T. Higuchi, Y. Hoshi, W. S. Hou, Y. B. Hsiung, H. J. Hyun, T. Iijima, K. Inami, R. Itoh, M. Iwabuchi, N. J. Joshi, T. Julius, J. H. Kang, T. Kawasaki, H. Kichimi, H. J. Kim, H. O. Kim, J. H. Kim, Y. J. Kim, K. Kinoshita, B. R. Ko, P. Kodyš, S. Korpar, P. Križan, P. Krokovny, T. Kuhr, T. Kumita, Y. J. Kwon, S. H. Kyeong, J. S. Lange, S. H. Lee, Y. Liu, D. Liventsev, R. Louvot, A. Matyja, S. McOnie, H. Miyata, R. Mizuk, G. B. Mohanty, E. Nakano, M. Nakao, H. Nakazawa, Z. Natkaniec, S. Neubauer, S. Nishida, O. Nitoh, T. Ohshima, S. Okuno, S. L. Olsen, P. Pakhlov, C. W. Park, H. Park, H. K. Park, M. Petrič, L. E. Piilonen, M. Röhrken, S. Ryu, H. Sahoo, Y. Sakai, O. Schneider, C. Schwanda, K. Senyo, M. E. Sevior, M. Shapkin, C. P. Shen, J. G. Shiu, P. Smerkol, E. Solovieva, M. Starič, K. Sumisawa, T. Sumiyoshi, Y. Teramoto, K. Trabelsi, S. Uehara, Y. Unno, S. Uno, P. Urquijo, Y. Usov, G. Varner, K. E. Varvell, K. Vervink, C. H. Wang, M. Z. Wang, P. Wang, Y. Watanabe, R. Wedd, J. Wicht, E. Won, B. D. Yabsley, Y. Yamashita, Z. P. Zhang, V. Zhilich, A. Zupanc

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We have made the first observation of Bs0→Ds(*)+Ds(*)- decays using 23.6fb⊃-1 of data recorded by the Belle experiment running on the Υ(5S) resonance. The branching fractions are measured to be B(Bs0→Ds+Ds-)=(1.03-0.32-0.25+0.39+0.26)%, B(Bs0→Ds*±Ds)= (2.75-0.71+0.83±0.69)%, and B(Bs0→Ds*+Ds*-)=(3.08-1.04- 0.86+1.22+0.85)%; the sum is B[Bs0→Ds(*)+Ds(*)-]=(6.85-1.30-1. 80+1.53+1.79)%. Assuming Bs0→Ds(*)+Ds(*)- saturates decays to CP-even final states, the branching fraction determines the ratio ΔΓs/cosφ, where ΔΓs is the difference in widths between the two Bs-B̄s mass eigenstates, and φ is a CP-violating weak phase. Taking CP violation to be negligibly small, we obtain ΔΓss=0. 147-0.030+0.036(stat)-0.041+0.042(syst), where Γs is the mean decay width.

Original languageEnglish
Article number201802
JournalPhysical Review Letters
Issue number20
Publication statusPublished - 2010 Nov 10


All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Cite this

Esen, S., Schwartz, A. J., Adachi, I., Aihara, H., Arinstein, K., Aulchenko, V., Aushev, T., Aziz, T., Bakich, A. M., Balagura, V., Barberio, E., Bay, A., Bischofberger, M., Bondar, A., Bozek, A., Bračko, M., Browder, T. E., Chang, M. C., Chang, P., ... Zupanc, A. (2010). Observation of Bs0→Ds(*)+Ds(*)- using e⊃+e⊃- collisions and a determination of the Bs-B̄s width difference ΔΓs. Physical Review Letters, 105(20), [201802]. https://doi.org/10.1103/PhysRevLett.105.201802