The Proton Electromagnetic Form Factor F2 and Quark Orbital Angular Momentum
نویسندگان
چکیده
We analyze the proton electromagnetic form factor ratio R(Q) = QF2(Q 2)/F1(Q ) as a function of momentum transfer Q within perturbative QCD. We find that the prediction for R(Q) at large momentum transfer Q depends on the exclusive quark wave functions, which are unknown. For a wide range of wave functions we find that QF2/F1 ∼ const at large momentum transfer, in agreement with recent JLAB data. The recent JLAB measurement of the Proton Electromagnetic Form Factor ratio [1, 2, 3] shows the puzzling behavior R(Q2) = QF2(Q )/F1(Q 2) ∼ const. at large Q. The form factors F1 and F2 are defined by the standard relation, < p′, s|J|p, s >= N̄(P ′, s′) ( γF1(Q ) + iσqν F2(Q 2) 2M )
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