Search for the radiative decay D s + → γρ 770 + $$ {D}_s^{+}\to \gamma \rho {(770)}^{+} $$

Abstract Using 7.33 fb −1 of e + e − collision data samples collected with the BESIII detector at center-of-mass energies between 4.128 and 4.226 GeV, we search for the radiative decay D s + → γρ 770 + $$ {D}_s^{+}\to \gamma \rho {(770)}^{+} $$ for the first time. A hint of D s + → γρ 770 + $$ {D}_s^{+}\to \gamma \rho {(770)}^{+} $$ is observed with a statistical significance of 2.5σ. The branching fraction of D s + → γρ 770 + $$ {D}_s^{+}\to \gamma \rho {(770)}^{+} $$ is measured to be (2.2 ± 0.9stat. ± 0.2syst. ) × 10 −4, corresponding to an upper limit of 6.1 × 10 −4 at the 90% confidence level.