A possible probe of the new fifth force

TL;DR

This paper proposes a method to detect the hypothetical protophobic fifth force by analyzing the ratio of charged pions at high energies in nucleus-nucleus collisions, offering a new experimental probe.

Contribution

It introduces a novel approach to test the existence of the protophobic fifth force through high-energy nuclear collision experiments.

Findings

The fifth force has negligible effects on standard observables.

It significantly influences the charged pion ratio at high kinetic energies.

The method is feasible with current experimental setups.

Abstract

The proposed protophobic fifth force in \emph{Phys. Rev. Lett. {\bf \emph{117}}, 071803 (2016)} recently attracts much attention. To confirm or refute the existence of this new interaction, here I propose a method to probe the protophobic fifth force in dense matter that formed in nucleus-nucleus collisions. As expected, the protophobic fifth force has negligible effects on the usual observables in nucleus-nucleus collisions. While the protophobic fifth force evidently affects the value of final positively and negatively charged pions ratio at very high kinetic energies. The signal thus could be used to probe the protophobic fifth force in dense matter by nucleus-nucleus collisions' experiments at current experimental equipments worldwide.