The X-ray properties of 3A 1907+09.
Abstract
A series of EXOSAT observations of the high-mass X-ray binary 3A1907+09 in 1984 early June show a spin-down of the neutron star since the discovery of X-ray pulsations in 1983 September by Tenma. The mildly eccentric orbit derived from Tenma data is confirmed and orbital parameters are refined. The pulse-averaged spectra were consistent with a hard power-law, photon index ≡1.2, with variable low-energy cut-off. The derived column density increased by ≡2×1022cm-2 over a period of time spanning the primary flare of the 8.37-day X-ray modulation cycle, with marginal evidence for a decrease during the secondary flare. The low-energy cut-off showed no pulse-phase dependency, unlike the spectral slope which showed marked softening during the deep pulse minimum.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- March 1987
- DOI:
- 10.1093/mnras/225.2.381
- Bibcode:
- 1987MNRAS.225..381C
- Keywords:
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- Exosat Satellite;
- X Ray Binaries;
- Light Curve;
- Neutron Stars;
- X Ray Spectra;
- Astrophysics