1999/04/26 by A. P. Reynolds, Reynolds, A. P., Alan Owens +8
Engineering · Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics (astro-ph) #FOS: Physical sciences #Mechanics and Biomechanics Studies #Pulsars and Gravitational Waves Research #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9904349
4 pages. Accepted for publication in A&A
arxiv created 1999/04/26 · openalex publication_date 1999/04/26 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A 0.5-200 keV BeppoSAX spectrum of the non-pulsating high-mass X-ray binary 4U1700-37 is presented. The spectrum is well characterized by the standard accreting pulsar model of an absorbed power-law with a photon index of 1.07 +0.02 -0.03, sharply modified by an exponential cutoff above 5.9 +/- 0.2 keV. The e-folding energy of the cutoff is 23.9 +/-0.5 keV. A soft bremsstrahlung component with a temperature of 0.2 +/- 0.1 keV is also required, together with a narrow iron line at 6.5 keV. Both continuum components are absorbed by a column of (5.1 +/- 0.2) x 10E22 atom/cm2. There is some evidence for the presence of a broad cyclotron absorption feature at ~37 keV, although we cannot exclude the possibility that this is due to an incorrect modeling of the continuum, or instrumental effects. The hypothesis that the compact object is a neutron star rather than a black hole seems most likely.