Nucleon momentum gap in asymmetric nuclear matter

TL;DR

This paper discusses the existence of a nucleon momentum gap in asymmetric nuclear matter caused by short-range correlations, with implications across physics disciplines.

Contribution

It introduces the concept of a nucleon momentum gap in asymmetric nuclei and links experimental evidence to theoretical implications.

Findings

Evidence of a proton momentum gap in neutron-rich nuclei

Support for a neutron momentum gap in proton-rich nuclei

Implications for nuclear physics and astrophysics

Abstract

For more than half a century, nucleons are considered to move continuously in the nuclei. Recent electron-scattering experiments indicate about 20$\sim$25\% nucleons in heavier nuclei are involved in the neutron-proton short-range correlations. Nucleons in the nuclei thus have abnormal behavior unlike those in the non-interaction fermi gas. In the neutron-rich nuclei, around the Fermi momentum, the neutron-proton short-range correlations lead to a momentum gap in the proton momentum distribution, which is circumstantially supported by the pionic experimental data. Likewise, there should also be a neutron momentum gap in the proton-rich nuclei. Nucleon momentum gap is thought to have profound and extensive implications in the studies ranging from particle physics to neutron stars as well as ultra-cold atomic gases.