ZFITTER -- An Analytical Program for Fermion Pair Production in e+e- Annihilation

D. Bardin; M. Bilenky; A. Chizhov; O. Fedorenko; S. Ganguli; A. Gurtu; M. Lokajicek; G. Mitselmakher; A. Olshevsky; J. Ridky; S. Riemann; T. Riemann; M. Sachwitz; A. Sazonov; A. D. Schaile; Yu. Sedykh; I. Sheer; L. Vertogradov

arXiv · hep-ph/9412201

ZFITTER -- An Analytical Program for Fermion Pair Production in e+e- Annihilation

D. Bardin·M. Bilenky·A. Chizhov·O. Fedorenko·S. Ganguli·A. Gurtu·M. Lokajicek·G. Mitselmakher·A. Olshevsky·J. Ridky·S. Riemann·T. Riemann·M. Sachwitz·A. Sazonov·A. D. Schaile·Yu. Sedykh·I. Sheer·L. Vertogradov

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Abstract

We describe how to use ZFITTER, a program based on a semi-analytical approach to fermion pair production in e+e- annihilation and Bhabha scattering. A flexible treatment of complete ${\cal O}(α)$ QED corrections, also including higher orders, allows for three calculational {\bf chains} with different realistic sets of restrictions in the photon phase space. {\tt ZFITTER} consists of several {\bf branches} with varying assumptions on the underlying hard scattering process. One includes complete ${\cal O}(α)$ weak loop corrections with a resummation of leading higher-order terms. Alternatively, an ansatz inspired from S-matrix theory, or several model-independent effective Born cross sections may be convoluted. The program calculates cross sections, forward-backward asymmetries, and for $τ$~pair production also the final-state polarization. Various {\bf interfaces} allow fits to be performed with different sets of free parameters.

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D. Bardin, M. Bilenky, A. Chizhov, O. Fedorenko, S. Ganguli, A. Gurtu, M. Lokajicek, G. Mitselmakher, A. Olshevsky, J. Ridky, S. Riemann, T. Riemann, M. Sachwitz, A. Sazonov, A. D. Schaile, Yu. Sedykh, I. Sheer, L. Vertogradov. 1995-09-29. ZFITTER -- An Analytical Program for Fermion Pair Production in e+e- Annihilation. https://arxiv.org/abs/hep-ph/9412201

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