Unusual quiescent X-ray activity from XTE J0421+560 (CI Cam)
| dc.creator | Parmar, A. N. | |
| dc.creator | Belloni, T. | |
| dc.creator | Orlandini, M. | |
| dc.creator | Fiume, D. Dal | |
| dc.creator | Orr, A. | |
| dc.creator | Masetti, N. | |
| dc.date | 2000-05-30 | |
| dc.date.accessioned | 2026-07-07T01:53:48Z | |
| dc.date.available | 2026-07-07T01:53:48Z | |
| dc.description | We report on BeppoSAX observations of the X-ray transient XTE J0421+560 in quiescence 156, 541, and ~690 days after the maximum of the 1998 April outburst. In the first observation the source was soft with a power-law photon index of 4.0 (+1.9 -0.9) and absorption, NH, of (1.1 +4.9 -1.1) X 10^21 atom/cm2. In the second observation, the source brightened by a factor ~15 in the 1-10 keV energy range, became significantly harder with a photon index of 1.86 (+0.27 -0.32) and was strongly absorbed with NH = (4.0 +/- 0.8) X 10^23 atom/cm2. There is evidence for a narrow emission line in both spectra at \~7 keV. In the third observation, the source had faded by a factor ~$8 from the previous observation to below the BeppoSAX detection level. It is possible that these variations result from orbital motion of a compact object around the B[e] star companion with the intense, absorbed, spectrum arising during passage through dense circumstellar material. If this is the case, the system may be continuing to exhibit periodic activity. | |
| dc.description | 4 pages. To appear in A&AL | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0005565 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0005565 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/1098 | |
| dc.subject | Astrophysics | |
| dc.title | Unusual quiescent X-ray activity from XTE J0421+560 (CI Cam) | |
| dc.type | text |