The tauola-photos-F environment for the TAUOLA and PHOTOS packages, release II
P. Golonka, B. Kersevan, T. Pierzchala, E. Richter-Was, Z. Was, M. Worek
TL;DR
The paper presents the tauola-photos-F environment, a versioning framework enabling tailored TAUOLA and PHOTOS distributions for diverse HEPEVT formats, physics initializations, RNGs, and compiler setups. It details a universal HEPEVT-based interface to incorporate tau spin correlations in production and decay, alongside a modular organization that supports multiple MC generators and hadronic currents. The work also introduces new 4π hadronic currents, a MC-TESTER tool for cross-generator comparisons, and a set of minor upgrades and practical considerations related to event-record schemes. Together, these contributions streamline the generation of compatible, spin-aware tau decays and radiative corrections within complex HEP simulation chains, facilitating collaboration-wide consistency and flexibility.
Abstract
We present the system for versioning two packages: the TAUOLA of tau-lepton decay and PHOTOS for radiative corrections in decays. The following features can be chosen in an automatic or semi-automatic way: (1) format of the common block HEPEVT; (2) version of the physics input (for TAUOLA): as published, as initialized by the CLEO collaboration, as initialized by the ALEPH collaboration (it is suggested to use this version only with the help of the collaboration advice), new optional parametrizations of matrix elements in 4-pi decay channels; (3) type of application: stand-alone, universal interface based on the information stored in the HEPEVT common block including longitudinal spin effects in the elementary Z/gamma* -> tau+ tau- process, extended version of the standard universal interface including full spin effects in the H/A -> tau+ tau- decay, interface for KKMC Monte Carlo, (4) random number generators; (5) compiler options.