Unquenched Charmonium with NRQCD
نویسنده
چکیده
We present results from a series of NRQCD simulations of the charmonium system, both in the quenched approximation and with nf = 2 dynamical quarks. The spectra show evidence for quenching effects of ∼ 10% in the Sand P -hyperfine splittings. We compare this with other systematic effects. Improving the NRQCD evolution equation altered the S-hyperfine by as much as 20 MeV, and we estimate O(αs) radiative corrections may be as large as 40%.
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تاریخ انتشار 2000