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Many models to describe the nature of heavy quarkonia have been proposed and one of the ways to test them is to analyze charmonium states produced in two-photon collisions through measuring their two-photon decay width( Γ γ γ ) and the angular distribution since they provide information on properties and internal structure of charmonium states. In this analysis, we use the decay channel γ γ → X → J / ψ γ , J / ψ → l + l − ( l = e or μ ) based on the 980.4 fb − 1 Belle data sample, where X is a charmonium state. Previously, Belle and CLEO collaborations have reported measurements of γ γ → χ c 2 ( 1 P ) → J / ψ γ , J / ψ → l + l − using 32.6 fb − 1 and 14.4 fb − 1 samples, respectively. By analyzing an about 30 times larger data sample, we can make a more precise measurement of χ c 2 ( 1 P ) and other rare charmonium states including a new charmonium(-like) state. In this paper, we discuss the proposal and method of the analysis and show the result of the feasibility study using Monte Carlo (MC) samples of γ γ → χ c 2 ( 1 P ) → J / ψ γ . |
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