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[Licence| Download | New Version Template] adrh_v3_0.tar.gz(582 Kbytes)
Manuscript Title: GR@PPA 2.8: initial-state jet matching for weak boson production processes at hadron collisions
Authors: Shigeru Odaka, Yoshimasa Kurihara
Program title: GR@PPA 2.8
Catalogue identifier: ADRH_v3_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 183(2012)1014
Programming language: Fortran; with some included libraries coded in C and C++.
Computer: All.
Operating system: Any UNIX-like system.
RAM: 1.6 Mega bytes at minimum
Keywords: GRACE, Hadron collision, Event generator, Jet matching, Parton shower, Weak boson production.
Classification: 11.2.

External routines: Bash and Perl for the setup, and CERNLIB, ROOT, LHAPDF, PYTHIA according to the user's choice.

Does the new version supersede the previous version?: No, this version supports only a part of the processes included in the previous versions.

Nature of problem:
We need to combine those processes including 0 jet and 1 jet in the matrix elements using an appropriate matching method, in order to simulate weak-boson production processes in the entire kinematical region.

Solution method:
The leading logarithmic components to be included in parton distribution functions and parton showers are subtracted from 1-jet matrix elements. Custom-made parton shower programs are provided to ensure satisfactory performance of the matching method.

Reasons for new version:
An initial-state jet matching method has been implemented.

Summary of revisions:
Weak-boson production processes associated with 0 jet and 1 jet can be consistently merged using the matching method.

Restrictions:
The built-in parton showers are not compatible with the PYTHIA new PS and the HERWIG PS.

Unusual features:
A large number of particles may be produced by the parton showers and passed to general-purpose event generators.

Running time:
About 10 min. for initialization plus 25 sec. for every 1k-event generation for W production in the LHC condition, on a 3.0-GHz Intel Xeon processor with the default setting.