Study of $B^{**}$ and $B_s^{**}$

Using 1 fb$^{-1}$ of data collected with the D\O\ detector of the Tevatron, the excited states containing a $b$ quark $B_1$, $B_2^*$ and $B_{s2}^*$ are selected in exclusive decays. A precise measurement of their masses, widths and branching rates is reported.