Sourabh Chutia ; Vishal Bhardwaj

08 November 2024

Abstract: We present here a preliminary Monte Carlo (MC) simulation study of $X(3872)\to J/\psi\gamma$ and $X(3872)\rightarrow \psi(2S)\gamma$ in the decay of $B\to (c\bar{c}\gamma)K$ where $B$ stands for $B^{\pm}$, $B^0$ and $K$ stands for $K^\pm$, $K^0_S$. The previous Belle measurement did not find any significant signal for $X(3872)\rightarrow \psi(2S)\gamma$. We plan to measure the ratio of BF $R_{\psi\gamma}=\{\mathcal{B}(X(3872)\rightarrow \psi(2S)\gamma)/\mathcal{B}(X(3872)\rightarrow J/\psi\gamma)\}$ to probe the nature of the state combining the $B$-meson data collected by the Belle (and the Belle II) detectors which is expected to increase the sensitivity and significance. $B\rightarrow \chi_{c1,c2}K$ where $\chi_{c1,c2}\rightarrow J/\psi\gamma$ will be used as calibration mode.