1998/08/08 by L. Burderi, A. R. King · 2 citations
Earth and Planetary Sciences · Physics and Astronomy · #Geophysics and Gravity Measurements #Pulsars and Gravitational Waves Research #Solar and Space Plasma Dynamics #astro-ph
paper · pdf · doi:10.1086/311611
(7 pages, 1 figure, accepted for publication in ApJ Letters)
arxiv created 1998/08/08 · openalex publication_date 1998/10/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
We show that observations of X-ray pulsing from SAX J1808.4-3658 place a firm upper limit of 13.8 m 1/3 km on the radius of the neutron star, where m is its mass in solar units. The limit is independent of distance, or assumptions about the magnetospheric geometry, and could be significantly tightened by observations of the pulsations in the near future. We discuss the implications for the equation of state and the possible neutron star mass.