NCKU-HEP-98-01/NHCU-HEP-98-01 Origin of the kT smearing in direct photon production
نویسندگان
چکیده
We show that the Sudakov factor from the resummation of double logarithms ln(s/k T ) contained in the distribution functions is responsible for the kT smearing mechanism employed in the next-to-leading-order QCD (αα 2 s) calculations of direct photon production. s is the center-of-mass energy, and kT the transverse momentum carried by a parton in a colliding hadron. This factor exhibits the appropriate s-dependent Gaussian width in kT , such that our predictions are in good agreement with experimental data.
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We show that the Sudakov factor from the resummation of double logarithms ln(s/k T ) contained in the distribution functions is responsible for the kT smearing mechanism employed in the next-to-leading-order QCD (αα 2 s) calculations of direct photon production. s is the center-of-mass energy, and kT the transverse momentum carried by a parton in a colliding hadron. This factor exhibits the app...
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