Energy dependence of femtoscopy properties of pion source in nuclear collisions

TL;DR

This study investigates how femtoscopy characteristics of pion emission regions depend on collision energy across various ion types, using normalized radii and volume to analyze non-symmetrical collisions without observing sharp changes predicted by some models.

Contribution

It introduces a normalized approach to femtoscopy parameters and extends analysis to non-symmetrical nucleus collisions within a unified framework.

Findings

No sharp changes in femtoscopic parameters with increasing energy.

Normalized radii and volume provide a consistent energy dependence analysis.

A generalized parameterization for the femtoscopic correlation function is proposed.

Abstract

In the paper energy dependence of femtoscopy characteristics of pion emission region at freeze-out is investigated for collisions of various ions and for all experimentally available energies. For the first time the normalized values of radii and volume of source are used for energy dependence. This approach allows us to expand the set of interaction types, in particular, on non-symmetrical nucleus-nucleus collisions which can be studied in the framework of common approach. There are no the sharp changing of femtoscopic parameter values, in particular, $R_{o}/R_{s}$ with increasing of $\sqrt{s_{NN}}$ which were predicted by some phenomenological models as signature of first order phase transition in strongly interacting matter. The generalized parameterization for femtoscopic correlation function is suggested.