Fast evolution of parton distributions
نویسنده
چکیده
I report on a numerical program for the evolution of parton distributions. The program uses the Mellin-transform method with an optimized contour. Due to this optimized contour the program needs only a few evaluations of the integrand and is therefore extremely fast. In addition, the program can also be used to reproduce the results of the x-space method. T tle of program: partonevolution Version: 1.0 Catalogue number: Program obtained from: http://www.fis.unipr.it/ ̃stefanw/partonevolution E-mail: [email protected] License: GNU Public License Computers: all Operating system: all Program language: C++ Memory required to execute: negligible (1 MB) Other programs called: none External files needed: none
منابع مشابه
ar X iv : h ep - p h / 99 05 51 7 v 1 2 7 M ay 1 99 9 1 Initial conditions and evolution of off - diagonal distributions
We briefly discuss the problem of specifying initial conditions for evolution of off-diagonal (skewed) parton distributions. We present numerical results to show that evolution rapidly washes out differences of input. Off-diagonal (or skewed) parton distributions provide important information about the nonper-turbartive structure of the nucleon [ 1]. They can in principle be measured in such pr...
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