New hadronic currents in TAUOLA: for confrontation with the experimental data

TL;DR

This paper reviews recent advances in implementing new hadronic currents into the TAUOLA Monte Carlo system, enhancing tau decay simulations and compatibility with experimental data from Belle and BaBar.

Contribution

Introduction of automated form factor options, alternative hadronic current parameterizations, and a universal interface for TAUOLA, improving simulation accuracy and flexibility.

Findings

Over 88% of tau hadronic width now modeled with new currents

Availability of a C++ interface based on HepMC for better integration

Enhanced tools for analyzing spin effects and decay processes

Abstract

The status of implementation of new hadronic currents into the Monte Carlo system for simulation of tau-lepton production and decay in high-energy accelerator experiments is reviewed. Since the tau-lepton conference in 2010 substantial progress was achieved: (i) For the TAUOLA Monte Carlo generator of tau-lepton decays, automated and simultaneous use of many versions of form factors for the calculation of optional weights for fits was developed and checked to work in the Belle and BaBar software environment. Alternative parameterizations of hadronic currents based on the Resonance Chiral approach are available now. This was achieved for more than 88% of the total tau hadronic width. (ii) the TAUOLA universal interface based on HepMC (the C++ event record) is available. This is the case for C++ users of PHOTOS Monte Carlo for radiative corrections in decays, as well. An algorithm for weighted events to explore spin effects in analysis of hard processes was prepared. (iii) Kernels featuring a complete first-order matrix element are available now for PHOTOS users interested in decays of Z and W bosons. New tests with different options of matrix elements for those and for Kl3 decays are available as well. Presented results illustrate the status of the projects performed in collaboration with Zofia Czyczula, Nadia Davidson, Tomasz Przedzinski, Olga Shekhovtsova, Elzbieta Richter-Was, Pablo Roig, Qingjun Xu and others.