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Manuscript Title: Numerical solution of Q2 evolution equations for fragmentation functions
Authors: M. Hirai, S. Kumano
Program title: ffevol1.0
Catalogue identifier: AELJ_v1_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 183(2012)1002
Programming language: Fortran77.
Computer: Tested on an HP DL360G5-DC-X5160.
Operating system: Linux 2.6.9-42.ELsmp.
RAM: 130 M bytes
Keywords: Fragmentation function, Q2 evolution, Quark, Gluon, QCD.
PACS: 13.87.Fh, 12.38.Bx.
Classification: 11.5.

Nature of problem:
This program solves timelike DGLAP Q2 evolution equations with or without next-to-leading-order αs effects for fragmentation functions. The evolved functions can be calculated for Dhg, Dhu, Dhubar, Dhd, Dhdbar, Dhs, Dhsbar, Dhc, Dhcbar, Dhb and Dhbbar of a random hedron h.

Solution method:
The DGLAP integrodifferential equations are solved by the Euler's method for the differentiation of ln Q2 and the Gauss-Legendre method for the x integral as explained in section 4 of the manuscript.

This program is used for calculating Q2 evolution of fragmentation functions in the leading order or in the next-to-leading order of αs. Q2 evolution equations are the timelike DGLAP equations. The double precision arithmetic is used. The renormalization scheme is the modified minimal subtraction scheme (MSbar ). A user provides initial fragmentation functions as the subroutines FF_INI and HQFF in the end of the distributed code FF_DGLAP.f. In FF_DGLAP.f, the subroutines are given by taking the HKNS07 (2) functions as an example of the initial functions. Then, the user inputs kinematical parameters in the file setup.ini as explained in section 5.2 of the manuscript.

Running time:
A few seconds on HP DL360G5-DC-X5160.