Interference in Exclusive Vector Meson Production in Heavy Ion Collisions

TL;DR

This paper explores quantum interference effects in the production of vector mesons during heavy ion collisions, highlighting the role of entanglement and the EPR paradox in these high-energy nuclear interactions.

Contribution

It introduces the concept of entanglement and non-local wave functions in vector meson production, linking quantum mechanics to heavy ion collision phenomena.

Findings

Interference effects depend on the meson transverse wavelength and impact parameter.

Decay products are entangled, affecting interference visibility.

The process exemplifies the EPR paradox in a high-energy physics context.

Abstract

Photons emitted from the electromagnetic fields of relativistic heavy ions can fluctuate into quark anti-quark pairs and scatter from a target nucleus, emerging as vector mesons. These coherent interactions are identifiable by final states consisting of the two nuclei and a vector meson with a small transverse momentum. The emitters and targets can switch roles, and the two possibilities are indistinguishable, so interference may occur. Vector mesons are negative parity so the amplitudes have opposite signs. When the meson transverse wavelength is larger than the impact parameter, the interference is large and destructive. The short-lived vector mesons decay before amplitudes from the two sources can overlap, and so cannot interfere directly. However, the decay products are emitted in an entangled state, and the interference depends on observing the complete final state. The non-local wave function is an example of the Einstein-Podolsky-Rosen paradox.