"Emission Line Properties of AGN from a post-COSTAR FOS HST
Joanna Kuraszkiewicz, Paul J. Green, D. Michael Crenshaw, Jay Dunn, Karl Forster, Marianne Vestergaard, & Thomas L. Aldcroft, 2004, ApJS, 150, 165 [21pp]
"Emission Line Properties of AGN from a pre-COSTAR FOS HST
Joanna Kuraszkiewicz, Paul J. Green, Karl Forster, Thomas L. Aldcroft, Ian Evans, & Anuradha Koratkar 2002, ApJS, 143, 257 [49pp]
Prior to the expected completion of the HST FOS atlas of AGN spectra, we have been analyzing spectra of the LBQS sample (956 QSOs), now nearly complete. ROSAT X-ray fluxes or upper limits exist for 90% of the sample. Here are some example fits showing the characteristic resolution, S/N and fit quality of these spectra:
We tackle the challenge of analyzing such a large sample of AGN spectra using software developed for the Chandra X-ray telescope, a NASA Great Observatory. We use the Sherpa fitting and plotting environment within the CIAO analysis package. This also allows not only multi-component user models for spectral fitting, but also analysis of the combined X-ray - UV - optical SEDs. Absorption lines in the UV spectra are identified and measured using FINDSL (Aldcroft 1995) and the iron emission features are fitted using a template generated from the UV spectrum of IZw1 (Vestergaard & Wilkes 1999). A detailed explanation of our techniques are presented in a (large postscript) poster by Forster et al. (1999) from the 1999 AAS HEAD meeting.
The FOS observations currently consist of pre-COSTAR
spectra. The pre-COSTAR spectra will appear in a complete atlas of
recalibrated HST FOS spectra of AGN (Evans, Koratkar, & Pesto in
prep), and contains proportions of
radio-loud (76%) and radio-quiet (24%) objects similar to the full FOS
sample. ROSAT PSPC observations are available for
approximately half of this sub-sample.