PHOKHARA 7.0 Monte Carlo generator: the narrow resonances implementation and new pion and kaon form factors

TL;DR

This paper introduces PHOKHARA 7.0, a Monte Carlo generator that models narrow resonances and incorporates new parameterizations of pion and kaon form factors, enhancing the simulation of meson pair production at high energies.

Contribution

It presents an improved implementation of narrow resonance effects and updated meson form factors in the PHOKHARA Monte Carlo generator, enabling more accurate simulations of experimental data.

Findings

Enhanced description of meson pair production at high energies.

Implementation of hadronic couplings to J/psi and psi(2S).

Better modeling of interference phenomena near narrow resonances.

Abstract

Experiments at high luminosity electron-positron colliders allow to study the kaon and the pion form factors in the time-like region up to high energies. Also the kaon and the pion pair production at and around the narrow resonances J/psi and psi(2S) can be investigated, with the interference between electromagnetic and hadronic amplitudes as one of the most interesting phenomenas. Parameterisations of charged and neutral kaon as well as pion form factors, which lead to an improved description of the data in the region of large invariant masses of the meson pair, are presented. They are implemented into the Monte Carlo generator PHOKHARA, together with the hadronic couplings of charged and neutral kaons to J/psi and psi(2S). The physics case as well as details of the implementation are discussed.