Dedicated searches suggest that the fraction of obscured Active Galactic Nuclei (AGN) decreases substantially with increasing luminosity. To explain these findings receding torus models have often been adopted. We have determined the intrinsic fraction of optical type-2 AGN at z

Suzaku observations of the blazar OJ 287 were performed in 2007 April 10-13 and November 7-9. They correspond to a quiescent and a flaring state, respectively. The X-ray spectra of the source can be well-described with single power-law models in both exposures. The derived X-ray photon index and the flux density at 1 keV were found to be Γ = 1.65±0

After our report on the flux decay of the neutron star transient SAX J1750.8-2900 (ATel #1662) we have continued monitoring the source with Swift-XRT in order to study its transition to quiescence. In these observations (performed between August 14th. and October 8th.) we detect the source at different flux levels, with the corresponding luminosity

Swift J1357.2-0933 is a confirmed very faint black hole X-ray transient and has a short estimated orbital period of 2.8 h. We observed Swift J1357.2-0933 for ˜50 ks with XMM-Newton in 2013 July during its quiescent state. The source is clearly detected at a 0.5-10 keV unabsorbed flux of ˜3 × 10-15 erg cm-2 s-1. If the source is located at a

The black hole (BH) binary V404 Cyg entered the outburst phase in 2015 June after 26 yr of X-ray quiescence, and with its behaviour broke the outburst evolution pattern typical of most BH binaries. We observed the entire outburst with the Swift satellite and performed time-resolved spectroscopy of its most active phase, obtaining over a thousand

IBIS-ISGRI observations on 2010-10-10 (Bordas et al. ATel #2919) as well as RXTE-PCA scans on 2010-10-09 (http://lheawww.gsfc.nasa.gov/users/craigm/galscan/html/EXO_1745-248.html) showed enhanced X-ray emission from the direction of the globular cluster Terzan 5. We analysed a ~500 s Swift-XRT observation of the field starting on 2010-10-10 01:32