Accurate classification of 28 objects detected in the 39 months Palermo Swift/BAT hard X-ray catalogue

P. Parisi; N. Masetti; E. Jiménez-Bailón; V. Chavushyan; R. Landi; A. Malizia; E. Palazzi; L. Bassani; A. Bazzano; A. J. Bird; G. Galaz; D. Minniti; L. Morelli; M. Schiavone; P. Ubertini

arXiv · 1112.4992

Accurate classification of 28 objects detected in the 39 months Palermo Swift/BAT hard X-ray catalogue

P. Parisi·N. Masetti·E. Jiménez-Bailón·V. Chavushyan·R. Landi·A. Malizia·E. Palazzi·L. Bassani·A. Bazzano·A. J. Bird·G. Galaz·D. Minniti·L. Morelli·M. Schiavone·P. Ubertini

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Abstract

Through an optical campaign performed at 4 telescopes located in the northern and the southern hemispheres, plus archival data from two on-line sky surveys, we have obtained optical spectroscopy for 28 counterparts of unclassified or poorly studied hard X-ray emitting objects detected with Swift/BAT and listed in the 39 months Palermo Swift/BAT hard X-ray catalogue. We have been able to pinpoint the optical counterpart of these high energy sources by means of X-ray observations taken with Swift/XRT or XMM which allowed us to restrict the positional uncertainty from few arcmin to few arcsec; satellite data also provided information on the X-ray spectra of these objects. We find that 7 sources in our sample are Type 1 AGN while 20 are Type 2 AGN, with their redshifts lying between 0.009 and 0.075; the remaining object is a Galactic cataclysmic variable (CV). In this work we provide optical information for all 28 sources and the results of the soft X-ray analysis of 3 out of 5 AGN observed with XMM/Newton.

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P. Parisi, N. Masetti, E. Jiménez-Bailón, V. Chavushyan, R. Landi, A. Malizia, E. Palazzi, L. Bassani, A. Bazzano, A. J. Bird, G. Galaz, D. Minniti, L. Morelli, M. Schiavone, P. Ubertini. 2011-12-21. Accurate classification of 28 objects detected in the 39 months Palermo Swift/BAT hard X-ray catalogue. https://arxiv.org/abs/1112.4992

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