Research on the Phase space of three- and four-body final states process

TL;DR

This paper derives analytical formulas for phase space factors in three- and four-body final states, aiding experimental data analysis and mechanism distinction in high-energy physics processes.

Contribution

It provides new analytical expressions for phase space calculations involving invariant mass variables in multi-body final states.

Findings

Formulas facilitate distinguishing different production mechanisms.

Application example demonstrates use in $e+p\to e+J/\psi+ p$ process.

Assists in searching for $P_c$ states at Electron-Ion collider.

Abstract

The analytical formulae for the phase space factors and the three-momenta of three- and four-body final states are derived for all sets of independent kinematic variables containing invariant mass variables. These formulae will help experimental physicist to perform the data analysis. As an example, we show how to use these formulae to distinguish the different mechanisms of $e+p\to e+J/\psi+ p$ process for searching the signals of $P_c$ states at the energy region of Electron-Ion collider at China (EicC).