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Title: Axion mass limit from observations of the neutron star in Cassiopeia A

Abstract

Direct Chandra observations of a surface temperature of isolated neutron star in Cassiopeia A (Cas A NS) and its cooling scenario which has been recently simultaneously suggested by several scientific teams put stringent constraints on poorly known properties of the superfluid neutron star core. It was found also that the thermal energy losses from Cas A NS are approximately twice more intensive than it can be explained by the neutrino emission. We use these unique data and well-defined cooling scenario to estimate the strength of KSVZ axion interactions with neutrons. We speculate that enlarged energy losses occur owing to emission of axions from superfluid core of the neutron star. If the axion and neutrino losses are comparable we find c{sub n}{sup 2}m{sub a}{sup 2}∼ 5.7× 10{sup -6} eV{sup 2}, where m{sub a} is the axion mass, and c{sub n} is the effective Peccei-Quinn charge of the neutron. (Given the QCD uncertainties of the hadronic axion models, the dimensionless constant c{sub n} could range from -0.05 to  0.14.)

Authors:
 [1]
  1. Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radiowave Propagation of the Russian Academy of Science (IZMIRAN), 142190 Troitsk, Moscow (Russian Federation)
Publication Date:
OSTI Identifier:
22373395
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 08; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AXIONS; COMPARATIVE EVALUATIONS; ENERGY LOSSES; EV RANGE; MASS; NEUTRINOS; NEUTRON STARS; NEUTRONS; QUANTUM CHROMODYNAMICS; SUPERFLUIDITY

Citation Formats

Leinson, Lev B., E-mail: leinson@yandex.ru. Axion mass limit from observations of the neutron star in Cassiopeia A. United States: N. p., 2014. Web. doi:10.1088/1475-7516/2014/08/031.
Leinson, Lev B., E-mail: leinson@yandex.ru. Axion mass limit from observations of the neutron star in Cassiopeia A. United States. doi:10.1088/1475-7516/2014/08/031.
Leinson, Lev B., E-mail: leinson@yandex.ru. 2014. "Axion mass limit from observations of the neutron star in Cassiopeia A". United States. doi:10.1088/1475-7516/2014/08/031.
@article{osti_22373395,
title = {Axion mass limit from observations of the neutron star in Cassiopeia A},
author = {Leinson, Lev B., E-mail: leinson@yandex.ru},
abstractNote = {Direct Chandra observations of a surface temperature of isolated neutron star in Cassiopeia A (Cas A NS) and its cooling scenario which has been recently simultaneously suggested by several scientific teams put stringent constraints on poorly known properties of the superfluid neutron star core. It was found also that the thermal energy losses from Cas A NS are approximately twice more intensive than it can be explained by the neutrino emission. We use these unique data and well-defined cooling scenario to estimate the strength of KSVZ axion interactions with neutrons. We speculate that enlarged energy losses occur owing to emission of axions from superfluid core of the neutron star. If the axion and neutrino losses are comparable we find c{sub n}{sup 2}m{sub a}{sup 2}∼ 5.7× 10{sup -6} eV{sup 2}, where m{sub a} is the axion mass, and c{sub n} is the effective Peccei-Quinn charge of the neutron. (Given the QCD uncertainties of the hadronic axion models, the dimensionless constant c{sub n} could range from -0.05 to  0.14.)},
doi = {10.1088/1475-7516/2014/08/031},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 08,
volume = 2014,
place = {United States},
year = 2014,
month = 8
}
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