Two-photon decays of charmonia from lattice QCD.
نویسندگان
چکیده
We make the first calculation in lattice QCD of two-photon decays of mesons. Working in the charmonium sector, using the Lehmann-Symanzik-Zimmermann reduction to relate a photon to a sum of hadronic vector eigenstates, we compute form factors in both the spacelike and timelike domains for the transitions eta c --> gamma*gamma* and chi(c0) --> gamma*gamma*. At the on-shell point, we find approximate agreement with experimental world-average values.
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ورودعنوان ژورنال:
- Physical review letters
دوره 97 17 شماره
صفحات -
تاریخ انتشار 2006