Origin of the k T smearing in direct photon production

نویسنده

  • Hung-Liang Lai
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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تاریخ انتشار 1998