We present BeppoSAX observations of the peculiar long period polar system V1309 Ori (RXJ0515.6+0105). The source was detected simultaneously at soft and, for the first time, at hard X-rays with the LEGS and the MECS detectors. Both, the LEGS and the MECS light curves are irregular with a bursting/flaring type behaviour indicating inhomogeneous accretion onto the white dwarf. This peculiar variability, together with an extreme high soft-to-hard X-ray luminosity ratio, indicates that in V1309 Ori accretion occurs predominantly in highly compressed chunks or "blobs" of matter. From coordinated ESO optical spectroscopy, we find indications that the magnetic field strength of the white dwarf is < 70 MG, not expected either from the 8 hr orbital period synchronism or from the strong soft-to-hard X-ray ratio suggesting alternative solutions for sustaining synchronism in this system.
de Martino, D., Barcaroli, R., Matt, G., Mouchet, M., Belloni, T., Beuermann, K., et al. (1998). BeppoSAX observations of the long period polar system V1309 Ori. ASTRONOMY & ASTROPHYSICS, 332(3), 904-908.
BeppoSAX observations of the long period polar system V1309 Ori
MATT, Giorgio;LA FRANCA, Fabio;
1998-01-01
Abstract
We present BeppoSAX observations of the peculiar long period polar system V1309 Ori (RXJ0515.6+0105). The source was detected simultaneously at soft and, for the first time, at hard X-rays with the LEGS and the MECS detectors. Both, the LEGS and the MECS light curves are irregular with a bursting/flaring type behaviour indicating inhomogeneous accretion onto the white dwarf. This peculiar variability, together with an extreme high soft-to-hard X-ray luminosity ratio, indicates that in V1309 Ori accretion occurs predominantly in highly compressed chunks or "blobs" of matter. From coordinated ESO optical spectroscopy, we find indications that the magnetic field strength of the white dwarf is < 70 MG, not expected either from the 8 hr orbital period synchronism or from the strong soft-to-hard X-ray ratio suggesting alternative solutions for sustaining synchronism in this system.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.