The scale dependent nuclear effects in parton distributions for practical applications
Abstract
The scale dependence of the ratios of parton distributions in a proton of a nucleus A and in the free proton, R_i^A(x,Q^2)=f_{i/A}(x,Q^2)/f_i(x,Q^2), is studied within the framework of the lowest order leadingtwist DGLAP evolution. By evolving the initial nuclear distributions obtained with the GRVLO and CTEQ4L sets at a scale Q_0^2, we show that the ratios R_i^A(x,Q^2) are only moderately sensitive to the choice of a specific modern set of free parton distributions. We propose that to a good first approximation, this parton distribution setdependence of the nuclear ratios R_i^A(x,Q^2) can be neglected in practical applications. With this result, we offer a numerical parametrization of R_i^A(x,Q^2) for all parton flavours i in any A>2, and at any 10^{6}le x le 1 and any 2.25 GeV^2le Q^2le 10^4 GeV^2 for computing cross sections of hard processes in nuclear collisions.
 Publication:

European Physical Journal C
 Pub Date:
 June 1999
 DOI:
 10.1007/s100529900005
 arXiv:
 arXiv:hepph/9807297
 Bibcode:
 1999EPJC....9...61E
 Keywords:

 High Energy Physics  Phenomenology;
 Nuclear Theory
 EPrint:
 14 pages, including 4 epsfigures