Monte-Carlo generator for e+e- annihilation into lepton and hadron pairs with precise radiative corrections
Bogoliubov Laboratory of Theoretical Physics, JINR, Dubna, 141980, Russia
2 Budker Institute for Nuclear Physics, Prospect Lavrent’eva 11, Novosibirsk, 630090, Russia
* e-mail: G.V.Fedotovich@inp.nsk.su
Published online: 12 April 2006
Recently, various cross sections of e+e- annihilation into hadrons were accurately measured in the energy range from 0.37 to 1.39 GeV with the CMD-2 detector at the VEPP-2M collider. In the π+π- channel a systematic uncertainty of 0.6% has been achieved. A Monte-Carlo Generator Photon Jets (MCGPJ) was developed to simulate events of Bhabha scattering as well as production of two charged pions, kaons and muons. Based on the formalism of structure functions, the leading logarithmic contributions related to the emission of photon jets in the collinear region are incorporated into the MC generator. Radiative corrections (RC) in the first order of α are accounted for exactly. The theoretical precision of the cross sections with RC is estimated to be better than 0.2%. Numerous tests of the program as well as a comparison with other MC generators and CMD-2 experimental data are presented.
© Springer-Verlag, 2006