Hard processes in massless perturbative QCD
All coefficient-function formulae linked below are
given in the MS scheme.
- The Fortran routines xclns3p.f and
xclsg3p.f for the parametrized third-order
coefficient functions for the longitudinal structure function, as
presented and briefly discussed in
hep-ph/0411112 (Phys. Lett. B606 (2005) 123-129).
- Their exact counterparts xclns3e.f, (non-singlet)
xclps3e.f (pure-singlet) and
xclgl3e.f (gluon) have been published, with the results for
F2, in hep-ph/0504242 (Nucl. Phys.
B724 (2005) 3-182 [!]) -- here is a version
without the appendices
- The corresponding routines for F2 are
xc2ns3p.f, xc2sg3p.f,
xc2ns3e.f, xc2ps3e.f
and xc2gl3e.f
- (Unoptimised) N-space subroutines for the parametrized non-singlet and
singlet expressions are provided by c2lmom.f
- Finally a FORM file is available with the complete
integer-N and x-space results for the above coefficient functions
The exact x-space numerics requires the weight-5 extension of the
Gehrmann/Remiddi package for the harmonic polylogarithms (HPLs) published in
hep-ph/0107173 = Comput. Phys. Commun. 141 (2001) 296.
NOTE: The sign of the &zeta5 term in the first line of
Eq. (4.19) is mistyped in the archived version second paper.
The third-order coefficient function for the odd-moment F3
- The Fortran routine xc3ns3p.f for the parametrized
third-order coefficient function for neutrino-antineutrino sum
F3 as given in hep-ph/0608307
(Nucl. Phys. B (Proc. Suppl.) 160 (2006) 44-50)
The full-length paper will the exact expression is not yet available.
These parametrizations have been given in
hep-ph/9907472 (Nucl. Phys. B568 (2000) 263-286) and
hep-ph/0006154 (Nucl. Phys. B588 (2000) 345-373).
While being accurate enough for normal applications, they are
considerably faster (especially for F2 and F3), than
the exact expressions of Sanchez Guillen et al. and Zijlstra / van Neerven.
NOTE: misprints in Eqs. (A.3) and (A.4) of hep-ph/0006154 have been corrected
in the ps-file linked above.
- The Fortran routines xc2ph2p.f and
xclph2p.f for the photonic coefficient functions
for F2 and FL published in
hep-ph/0110331 (Nucl. Phys. B621 (2002) 413-458).
- The Fortran routine xk3cnvp.f for the
parametrized convolutions contributing at NNLO for
F2,NS and
F3
.
- The corresponding convolutions entering at N3LO are given
in xk24cnvp.f for F
2,NS and in xk34cnvp.f for
F3,NS
These results have been presented in hep-ph/0103123
(Nucl. Phys. B603 (2001) 42-68). The approximations for the third-order
coefficient functions in that paper have been superseded by the above exact
results.
- The Fortran routines xcttns2e.f for the
transverse, xcltns2e.f for the longitudinal
and xcatns2e.f for the asymmetric coefficient
functions at the second order in aS, recalculated in
hep-ph/0604053 (Phys. Lett. B638 (2006) 61-67)
- The FORM file including (besides the
splitting-function differences) these and the lower-order results
These results confirm the calculations of Rijken and van Neerven in 1996/97
(there are some misprints in their papers). The numerical routines require
the HPL package by Gehrmann and Remiddi mendtioned above.