Identification of $D_2^{\ast }(3000)$ as the $D_2^{\ast }(2^3{P}_2)$ and exploring potential of undiscovered $2^{+}$ mesons via $B$ decays

Abstract

Following the discovery of the $D_2^{\ast }(3000)$, its mass and full width have been extensively studied. Yet its nature remains undetermined to date. Since it was discovered through nonleptonic decay of $B$ meson and the corresponding cascade process, we therefore in this paper investigate the nonleptonic and semileptonic decays of $B$ meson to $J^P=2^{+}$ charmed mesons using the Bethe-Salpeter equation approach. Our calculations on nonleptonic $B$ decays reveal that the unconfirmed resonance $D_2^{\ast }(3000)$ aligns well with $D_2^{\ast }(2^3{P}_2)$ predictions. Other candidates, including $D_2^{\ast }(1^3{F}_2)$, $D_2^{\ast }(3^3{P}_2)$, and $D_2^{\ast }(2^3{F}_2)$, are excluded due to their very small branching ratios in $B$ decays. Considering that the $D_2^{\ast }(1F)$, $D_2^{\ast }(3P)$, and $D_2^{\ast }(2F)$ have not yet been experimentally observed, we investigate the feasibility of their detection in $B$-meson decays.

Comments: 28 pages, 7 figures