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THE MASS AND RADIUS OF THE NEUTRON STAR IN 4U 1820-30

Journal Article · · Astrophysical Journal
; ; ;  [1]
  1. University of Arizona, Department of Astronomy, 933 N. Cherry Ave., Tucson, AZ 85721 (United States)
We report on the measurement of the mass and radius of the neutron star in the low-mass X-ray binary 4U 1820-30. The analysis of the spectroscopic data on multiple thermonuclear bursts yields well-constrained values for the apparent emitting area and the Eddington flux, both of which depend in a distinct way on the mass and radius of the neutron star. The distance to the source is that of the globular cluster NGC 6624, where the source resides. Combining these measurements, we uniquely determine the probability density over the stellar mass and radius. We find the mass to be M = 1.58 {+-} 0.06 M{sub sun} and the radius to be R = 9.1 {+-} 0.4 km.
OSTI ID:
21457063
Journal Information:
Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 719; ISSN ASJOAB; ISSN 0004-637X
Country of Publication:
United States
Language:
English

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