Study of Two-Body $e^{+}{e}^{-}\to B_s^{(\ast )}{\bar{B}}_s^{(\ast )}$ Production in the Energy Range from 10.77 to 11.02 GeV

Abstract

We report results on the studies of the $e^{+}{e}^{-}\to B_s^{(\ast )}{\bar{B}}_s^{(\ast )}$ processes. The results are based on a $121.4$ fb${}^{-1}$ data sample collected with the Belle detector at the center-of-mass energy near the $\hat{I}\yen (10860)$ peak and $16.4$ fb${}^{-1}$ of data collected at 19 energy points in the range from 10.77 to 11.02 GeV. We observe a clear $e^{+}{e}^{-}\to \hat{I}\yen (10860)\to B_s^{(\ast )}{\bar{B}}_s^{(\ast )}$ signal, with no statistically significant signal of $e^{+}{e}^{-}\to \hat{I}\yen (11020)\to B_s^{(\ast )}{\bar{B}}_s^{(\ast )}$. The relative production ratio of $B_s^{\ast }{\bar{B}}_s^{\ast }$, $B_s{\bar{B}}_s^{\ast }$, and $B_s{\bar{B}}_s$ final states at $\sqrt{s}=10.866$ GeV is measured to be $7:$ $0.856\pm 0.106(stat.)\pm 0.053(syst.):$ $0.645\pm 0.094(stat.{)}_{-0.033}^{+0.030}(syst.)$. An angular analysis of the $B_s^{\ast }{\bar{B}}_s^{\ast }$ final state produced at the $\hat{I}\yen (10860)$ peak is also performed.

22 page, 6 figures