The tau leptons theory and experimental data: Monte Carlo, fits, software and systematic errors

TL;DR

This paper reviews the TAUOLA Monte Carlo generator for tau lepton decays, discusses recent developments in hadronic currents, new decay channels, and the importance of detailed data fitting for model accuracy, with applications to LHC phenomenology.

Contribution

It introduces new hadronic currents, decay channels, and parametrizations, emphasizing the importance of detailed data fitting for tau decay models and extending applications to LHC phenomenology.

Findings

Proper data fitting is crucial for accurate tau decay models.

New hadronic currents and decay channels improve simulation accuracy.

Applications to W, Z, H decays at LHC are demonstrated.

Abstract

Status of tau lepton decay Monte Carlo generator TAUOLA is reviewed. Recent efforts on development of new hadronic currents are presented. Multitude new channels for anomalous tau decay modes and parametrization based on defaults used by BaBar collaboration are introduced. Also parametrization based on theoretical considerations are presented as an alternative. Lesson from comparison and fits to the BaBar and Belle data is recalled. It was found that as in the past, in particular at a time of comparisons with CLEO and ALEPH data, proper fitting, to as detailed as possible representation of the experimental data, is essential for appropriate developments of models of tau decays. In the later part of the presentation, use of the TAUOLA program for phenomenology of W,Z,H decays at LHC is adressed. Some new results, relevant for QED bremsstrahlung in such decays are presented as well.