Observation of a new D_sJ meson in B+->D0BD0K+ decays

We report the observation of a new $D_{sJ}$ meson produced in $B^{+} \to \bar{D}^{0} D_{sJ} \to \bar{D}^{0} D^{0} K^{+}$\mathrm{.}Thisstatehasamassof$M=2708 \pm 9 ^{+11}{-10} \rm{MeV}/{\it c}^{2}$,awidth$\Gamma = 108 \pm 23 ^{+36}{-31} ~\rm{MeV}/ {\it c}^{2}$anda$1^{-}$ spin-parity. The results are based on an analysis of 449 million $B\bar{B}$ events collected at the $\mathrm{{\rm Y}}(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider.