arXiv subjects
Publications and source records attributed to Shen Cheng-Ping.
In this paper, I review recent progress in the study of the $XYZ$ particles at Belle. I only focus on studies with charmonium and one or more light mesons in the final states. This covers the X(3872), X(3915), Y(4140), X(4350), and the charged Z states.
In measuring the $\psip$ radiative decays at BESII, contribution of the background is serious in most of the final states. To extract the number of signal events, a fit to the $χ^2$ distribution of kinematic fit using signal and background components is proposed. Extensive Monte-Carlo simulations (MCS) are performed, and the results show that the shape of $χ^2$ distribution of the signal channel looks different from those of the background channels, thus it provides us by fitting the $χ^2$ distribution of the data to extract the number of signal events. An input-output test is performed using MCS, and the uncertainty of the fit method is found to be less than 2%.