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GENXICC2.0: An upgraded version of the generator for hadronic production of double heavy baryons ΞccΞcc, ΞbcΞbc and ΞbbΞbb

Department of Physics, Chongqing University, Chongqing 400044, China; CCAST (World Laboratory), P.O. Box 8730, Beijing 100190, China; Institute of Theoretical Physics, Chinese Academy of Sciences, P.O. Box 2735, Beijing 100190, China; Institute of High Energy Physics, Chinese Academy of Sciences, P.O. Box 918(4), Beijing 100049, PR China
Computer Physics Communications (Impact Factor: 2.41). 06/2010; 181(6):1144-1149. DOI: 10.1016/j.cpc.2010.02.008
Source: DBLP

ABSTRACT An upgraded (second) version of the package GENXICC ({\bf A Generator for Hadronic 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: in Comput. Phys. Commun. {\bf 177} (2007) 467-478]) is presented. Users, with this version being implemented in PYTHIA and a GNU C compiler, may simulate full events of the production in various experimental environments conveniently. In comparison with the previous version, in order to implement it in PYTHIA properly, a subprogram for the fragmentation of the produced double heavy diquark to the relevant baryon is complemented and the interphase of the generator to PYTHIA is changed accordingly. In the subprogram, with explanation, certain necessary assumptions (approximations) are made so as to conserve the momenta and the QCD `color' flow for the fragmentation. Comment: 15 pages, 2 figures

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