The Monte Carlo Generator for J/ψ Decays with Angular Distribution

We present a Monte Carlo scheme to generate events of J/ψ decays with angular distributions based
on the acceptance--rejection sampling method. We test this scheme with J/ψ → pp and J/ψ → ΛΛ → ppπ⁺π^-, and the results show that the input angular distributions are well reproduced, and efficiency of the HOWL generator of this scheme is also discussed.