Squeezed particle-antiparticle correlations

TL;DR

This paper discusses a theoretical study proposing experimental methods to detect squeezed particle-antiparticle correlations, which indicate in-medium mass modifications in hot dense matter created in heavy ion collisions.

Contribution

It introduces a new phenomenological approach to search for squeezed correlations in phi phi and K+ K- pairs at RHIC energies, linking them to in-medium mass shifts.

Findings

Proposes analyzing the correlation function as a function of pair average momentum.

Highlights the potential to observe BBC signals in specific particle pairs.

Discusses the impact of mass-shifts on traditional particle correlations.

Abstract

A novel type of correlation involving particle-antiparticle pairs was found out in the 1990's. Currently known as Squeezed or Back-to-Back Correlations (BBC), they should be present if the hadronic masses are modified in the hot and dense medium formed in high energy heavy ion collisions. Although well-established theoretically, such hadronic correlations have not yet been observed experimentally. In this phenomenological study we suggest a promising way to search for the BBC signal, by looking into the squeezed correlation function of phi phi and K^+ K^- pairs at RHIC energies, as function of the pair average momentum, K_{12}=(k_1+k_2)/2. The effects of in-medium mass-shift on the identical particle correlations (Hanbury-Brown & Twiss effect) are also discussed.