Evidence for B^(*)_s Production at the Upsilon(5S)

Based on data collected by the CLEO III detector at CESR, we started a series of investigations to open the mysteries of the $\Upsilon$(5S) resonance decay properties. $B_s$ mesons are expected to decay predominantly into $D_s$ meson, while the lighter $B$ mesons decay into $D_s$ only about 10% of the time. We exploit this difference to present the first evidence of a substantial production of $B_s$ mesons at the $\Upsilon$(5S) resonance. We make here a preliminary model dependent estimate of the ratio of $B_s^{(*)}\bar{B}_s^{(*)}$ to the total $b\bar{b}$ quark pair production at the $\Upsilon$(5S) energy to be $(21\pm 3 \pm 9)$%.