First results on a medium-deep X-ray survey in the "new" 5-10 keV band carried out with the MECS detectors onboard BeppoSAX are presented. The High Energy Llarge Area Survey (HELLAS) is aimed to directly explore a band where the energy density of the X-ray background is more than twice than that in the soft (0.5-2.0 keV) band. The optical identification follow-up of the first ten HELLAS hard X-ray sources indicate that Active Galactic Nuclei are the dominant population at 5-10 keV fluxes of the order of 10(-13) erg cm(-2) s(-1). We discuss the implications of these findings for the AGN synthesis models for the XRB. (C) 2000 COSPAR. Published by Elsevier Science Ltd.
Comastri, A., Fiore, F., Giommi, P., LA FRANCA, F., Elvis, M., Matt, G., et al. (2000). The BeppoSAX view of the hard X-ray background. ADVANCES IN SPACE RESEARCH, 25(3-4), 833-838 [10.1016/S0273-1177(99)00850-9].
The BeppoSAX view of the hard X-ray background
LA FRANCA, Fabio;Matt G;
2000-01-01
Abstract
First results on a medium-deep X-ray survey in the "new" 5-10 keV band carried out with the MECS detectors onboard BeppoSAX are presented. The High Energy Llarge Area Survey (HELLAS) is aimed to directly explore a band where the energy density of the X-ray background is more than twice than that in the soft (0.5-2.0 keV) band. The optical identification follow-up of the first ten HELLAS hard X-ray sources indicate that Active Galactic Nuclei are the dominant population at 5-10 keV fluxes of the order of 10(-13) erg cm(-2) s(-1). We discuss the implications of these findings for the AGN synthesis models for the XRB. (C) 2000 COSPAR. Published by Elsevier Science Ltd.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
