Measurement of the Branching Fraction of \boldmath{ψ(2S) \to γ π^0}

Based on (2712.4\pm14.1)\times10^{6}~\psi(2S) events, 7.9 fb^{-1} \psi(3773) data, and 0.8 fb^{-1} off-resonance data samples collected with the BESIII detector, we measure the branching fraction of \psi(2S)\rightarrow\gamma\pi^{0} and e^{+}e^{-}\rightarrow\gamma\pi^{0} form factor at momentum transfers Q^{2}\sim13 GeV^{2}. The e^{+}e^{-}\rightarrow\gamma\pi^{0} cross section is fitted with considering the interference between the \psi(2S) and continuum... Show more