The effect of off-diagonal parton distributions in diffractive vector meson electroproduction
نویسندگان
چکیده
We present a simple physical description of the off-diagonal gluon distribution g(x, x′, Q2) and splitting function Pgg(x, x ′) which enter the amplitude for diffractive vector meson production. We study the off-diagonal effects both on the evolution in Q2 and on the input distribution. We predict the ratio R of the off-diagonal to the diagonal gluon density, x′g(x, x′, Q2)/xg(x,Q2), as a function of the kinematic variables. ∗Petersburg Nuclear Physics Institute, SU-188 350 Gatchina, Russia.
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