We present a BeppoSAX observation of AM Her during a prolonged low state. The source was observed for similar to 4 hrs at a flux level comparable to previous low states, followed by a rapid (similar to 40 min) drop by a factor of similar to 7 to the deepest X-ray low state ever detected. While the active phase X-ray flux is likely to be accretion induced, coronal emission from the secondary may contribute significantly during the inactive phase. The timescale of this dramatic change in the accretion rate is of the order of the dynamical timescale of the secondary star; no available model can satisfactorily explain the evolution of the X-ray flux detected in these BeppoSAX data.
de Martino, D., Gansicke, B.t., Matt, G., Mouchet, M., Belloni, T., Beuermann, K., et al. (1998). A deep X-ray low state of AM Herculis. ASTRONOMY & ASTROPHYSICS, 333(2), L31-L34.
A deep X-ray low state of AM Herculis
MATT, Giorgio;
1998-01-01
Abstract
We present a BeppoSAX observation of AM Her during a prolonged low state. The source was observed for similar to 4 hrs at a flux level comparable to previous low states, followed by a rapid (similar to 40 min) drop by a factor of similar to 7 to the deepest X-ray low state ever detected. While the active phase X-ray flux is likely to be accretion induced, coronal emission from the secondary may contribute significantly during the inactive phase. The timescale of this dramatic change in the accretion rate is of the order of the dynamical timescale of the secondary star; no available model can satisfactorily explain the evolution of the X-ray flux detected in these BeppoSAX data.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
