GENXICC2.0: An Upgraded Version of the Generator for Hadronic Production of Double Heavy Baryons $\Xi_{cc}$, $\Xi_{bc}$ and $\Xi_{bb}$

摘要

An upgraded (second) version of the package GENXICC ({\bf A Generator forHadronic Production of the Double Heavy Baryons $\Xi_{cc}$, $\Xi_{bc}$ and$\Xi_{bb}$ by C.H. Chang, J.X. Wang and X.G. Wu,} [its first version: inComput. Phys. Commun. {\bf 177} (2007) 467-478]) is presented. Users, with thisversion being implemented in PYTHIA and a GNU C compiler, may simulate fullevents of the production in various experimental environments conveniently. Incomparison with the previous version, in order to implement it in PYTHIAproperly, a subprogram for the fragmentation of the produced double heavydiquark to the relevant baryon is complemented and the interphase of thegenerator to PYTHIA is changed accordingly. In the subprogram, withexplanation, certain necessary assumptions (approximations) are made so as toconserve the momenta and the QCD `color' flow for the fragmentation.