Search for a $1^{-+}$ molecular state via $e^{+}{e}^{-}\to \gamma D_s^{+}{D}_{s1}^{-}(2536)+c.c.$

Abstract

We search, for the first time, for an exotic molecular state with quantum numbers $J^{PC}=1^{-+}$, called $X$, via the process $e^{+}{e}^{-}\to \gamma D_s^{+}{D}_{s1}^{-}(2536)+c.c.$ using data samples corresponding to a luminosity of $5.8\mathrm{f}{\mathrm{b}}^{-1}$ across center-of-mass energies from 4.612 to 4.951~GeV, collected with the BESIII detector operating at the BEPCII collider. No statistically significant signal is observed. The upper limits on the product of cross-section and branching fraction $\sigma (e^{+}{e}^{-}\to \gamma X)\times \mathcal{B}(X\to D_s^{+}{D}_{s1}^{-}(2536)+c.c.)$ at 90\% confidence level are reported for each energy point, assuming the $X$ mass to be 4.503~GeV/$c^2$ and the width 25, 50, 75, and 100~MeV, respectively.

13 pages,5 figures