Exotics from Heavy Ion Collisions

TL;DR

This paper proposes using relativistic heavy ion collisions to distinguish between hadronic molecular and multi-quark exotic states by analyzing their yield differences predicted by the coalescence model.

Contribution

It introduces a method to discriminate exotic hadron structures based on yield ratios in heavy ion collisions, providing a new approach in hadronic physics.

Findings

Compact multi-quark states have significantly lower yields than statistical model predictions.

Loosely bound hadronic molecules have higher yields, often double or more than statistical expectations.

Some heavy exotic states could be experimentally observed at RHIC and LHC.

Abstract

Discriminating hadronic molecular and multi-quark states is a long standing problem in hadronic physics. We propose here to utilize relativistic heavy ion collisions to resolve this problem, as exotic hadron yields are expected to be strongly affected by their structures. Using the coalescence model, we find that the exotic hadron yield relative to the statistical model result is typically an order of magnitude smaller for a compact multi-quark state, and larger by a factor of two or more for a loosely bound hadronic molecule. We further find that some of the newly proposed heavy exotic states could be produced and realistically measured at RHIC and LHC.