Title: Integral Spectroscopy of Radio Quiet QSOs


Proposal ID: 0120214
Subject category: Extragalactic Object
Principal investigator: Orr
Institute: ESTEC/ESA


Abstract

By many of their properties radio quiet quasars (RQQs) occupy a poorly understood intermediary position between Seyfert 1 galaxies (Sy1s) and radio loud quasars (RLQs). In the X-ray domain there are, however, several notable differences between these 3 categories of Active Galactic Nuclei (AGN). We propose to observe with INTEGRAL the three brightest RQQs in the X-ray band, E 1821+643, HE 1029-1401 and 2251-178}, in order to measure the spectral shape of their hard X-ray emission, which is not well known up to now. Our aim is: a) to test the presence of Compton reflection components, ionized or neutral and b) measure the shape and energy of the high energy spectral cut-off. The scientific goal of this proposal is to obtain a better understanding of the hard spectral energy distribution of RQQs, in particular at high energies. We will thereby gain deeper insight on the relationship between RQQs, Sy1s and RLQs. This will be achieved by taking a single exposure of 500 ks per quasar.