We discuss results of a multiwavelength study of a sample of ∼ 70 radio galaxies, selected in the soft gamma-ray band from INTEGRAL and Swift/BAT catalogues. The sample contains a significantly larger fraction of giant radio galaxies (linear size > 0.7 Mpc) than typically found in radio surveys. These giant objects are consistent with being powered by efficient accretion, and with having experienced episodes of restarting activity. Concerning the absorption properties of the whole sample, we find a higher detection rate of 21 cm H1 absorption among X-ray absorbed sources. This might suggest that at least part of the X-ray obscuration is due to atomic hydrogen seen at radio frequencies, and that could reside at distances larger than the classical pc-scale torus.
Ursini, F., Bassani, L., Panessa, F., Bruni, G., Bazzano, A., Bird, A.J., et al. (2019). High-energy view of hard X-ray selected radio galaxies. In INTEGRAL conference and AHEAD gamma-ray workshop INTEGRAL looks AHEAD to multi-messenger astronomy (pp.170-173). Societa Astronomica Italiana.
High-energy view of hard X-ray selected radio galaxies
Ursini F.
;
2019-01-01
Abstract
We discuss results of a multiwavelength study of a sample of ∼ 70 radio galaxies, selected in the soft gamma-ray band from INTEGRAL and Swift/BAT catalogues. The sample contains a significantly larger fraction of giant radio galaxies (linear size > 0.7 Mpc) than typically found in radio surveys. These giant objects are consistent with being powered by efficient accretion, and with having experienced episodes of restarting activity. Concerning the absorption properties of the whole sample, we find a higher detection rate of 21 cm H1 absorption among X-ray absorbed sources. This might suggest that at least part of the X-ray obscuration is due to atomic hydrogen seen at radio frequencies, and that could reside at distances larger than the classical pc-scale torus.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
