Fine-structure splittings of excited P-and D-wave states in charmonium

AbstractIt is shown that, in the relativistic case, the fine-structure splittings of the excited 23PJ and 33PJ states in charmonium are as large as those of the 13PJ state if the same value of αs(μ)≈0.36 is used. The predicted mass of M(23P0)=3.84 GeV appears to be 120 MeV lower than the center of gravity of the 23PJ multiplet and lies below the D $$\bar D$$ * threshold. Our value of M(23P0) is nearly 80 MeV lower than that from the Godfrey and Isgur article [Phys. Rev. D 32, 189 (1985)], while the differences in other masses are not greater than 20 MeV.