Measurement of branching fraction of $D_s^{\ast +}\to D_s^{+}{\pi }^0$ relative to $D_s^{\ast +}\to D_s^{+}\gamma$

Based on 7.33 fb${}^{-1}$ of $e^{+}{e}^{-}$ collision data taken at center-of-mass energies between 4.128 and 4.226 GeV with the BESIII detector, we measure the branching fraction of $D_s^{\ast +}\to D_s^{+}{\pi }^0$ relative to that of $D_s^{\ast +}\to D_s^{+}\gamma$ to be $(6.16\pm 0.43\pm 0.19)\mathrm{\%}$. The first uncertainty is statistical and the second one is systematic. By using the world average value of the branching fraction of $D_s^{\ast +}\to D_s^{+}{e}^{+}{e}^{-}$, we determine the branching fractions of $D_s^{\ast +}\to D_s^{+}\gamma$ and $D_s^{\ast +}\to D_s^{+}{\pi }^0$ to be $(93.57\pm 0.44\pm 0.19)\mathrm{\%}$ and $(5.76\pm 0.44\pm 0.19)\mathrm{\%}$, respectively.