Electromagnetic vertex function of the pion at T > 0
نویسندگان
چکیده
The matrix element of the electromagnetic current between pion states is calculated in quenched lattice QCD at a temperature of T = 0.93 T c. The nonperturbatively improved Sheikholeslami-Wohlert action is used together with the corresponding O(a) improved vector current. The electromagnetic vertex function is extracted for pion masses down to 360 MeV and momentum transfers Q 2 ≤ 2.7 GeV
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