Work

Trace Anomaly as Signature of Conformality in Neutron Stars

Year: 2022

Type: article

Abstract: We discuss an interpretation that a peak in the sound velocity in neutron star matter, as suggested by the observational data, signifies strongly coupled conformal matter. The normalized trace anomaly is a dimensionless measure of conformality leading to the derivative and the nonderivative contributions to the sound velocity. We find that the peak in the sound velocity is attributed to the derivative contribution from the trace anomaly that steeply approaches the conformal limit. Smooth continuity to the behavior of high-density QCD implies that the matter part of the trace anomaly may be positive definite. We discuss a possible implication of the positivity condition of the trace anomaly on the M-R relation of the neutron stars.

Source: Physical Review Letters

DOI: 10.1103/physrevlett.129.252702

Authors: Yuki Fujimoto, Kenji Fukushima, Larry D. McLerran, Michał Praszałowicz

Institutions: University of Washington, The University of Tokyo, Jagiellonian University

Language: English

Topic: Pulsars and Gravitational Waves Research

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: U.S. Department of Energy, Japan Society for the Promotion of Science