ExHuME 1.3: A Monte Carlo event generator for exclusive diffraction

Abstract We have written the Exclusive Hadronic Monte Carlo Event (ExHuME) generator. ExHuME is based around the perturbative QCD calculation of Khoze, Martin and Ryskin of the process p p → p + X + p , where X is a centrally produced colour singlet system. Program summary Title of program:ExHuME Catalogue identifier:ADYA_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ ADYA_v1_0 Program obtainable from:CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions:None Programming language used:C++, some FORTRAN Computer:Any computer with UNIX capability. Users should refer to the README file distributed with the source code for further details Operating system:Linux, Mac OS X No. of lines in distributed program, including test data, etc.:111 145 No. of bytes in distributed program, including test data, etc.: 791 085 Distribution format:tar.gz RAM:60 MB External routines/libraries:LHAPDF [ http://durpdg.dur.ac.uk/lhapdf/ ], CLHEP v1.8 or v1.9 [L. Lonnblad, Comput. Phys. Comm. 84 (1994) 307; http://wwwinfo.cern.ch/asd/lhc++/clhep/ ] Subprograms used:Pythia [T. Sjostrand et al., Comput. Phys. Comm. 135 (2001) 238], HDECAY [A. Djouadi, J. Kalinowski, M. Spira, HDECAY: A program for Higgs boson decays in the standard model and its supersymmetric extension, Comput. Phys. Comm. 108 (1998) 56, hep-ph/9704448]. Both are distributed with the source code Nature of problem:Central exclusive production offers the opportunity to study particle production in a uniquely clean environment for a hadron collider. This program implements the KMR model [V.A. Khoze, A.D. Martin, M.G. Ryskin, Prospects for New Physics observations in diffractive processes at the LHC and Tevatron, Eur. Phys. J. C 23 (2002) 311, hep-ph/0111078 ], which is the only fully perturbative model of exclusive production. Solution method:Monte Carlo techniques are used to produce the central exclusive parton level system. Pythia routines are then used to develop a realistic hadronic system. Restrictions:The program is, at present, limited to Higgs, di-gluon and di-quark production. However, in principle it is not difficult to include more. Running time:Approximately 10 minutes for 10000 Higgs events on an Apple 1 GHz G4 PowerPC.