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An Atlas of Recalibrated HST FOS Spectra of Active
Galactic Nuclei and Quasars
The following atlas provides spectral fits data and browse files
for all successful pre-COSTAR spectra using the Faint Object
Spectrograph of AGNs (Active Galactic Nuclei). A very complete
discussion of the uniform flux and wavelength calibrations of these
spectra, including common instrumental artifacts that can appear in
FOS data is given in
Evans and Koratkar (2004). The data list includes
221 AGNs. Where possible, and in most cases, these spectra have been
clipped at overlapping wavelengths and merged to form a panchromatic
spectrum. The target list was compiled from a PI object description in
the keywords denoted by "AGN, quasar, Seyfert," etc., as well as others
designated by the PI as "galaxy" that should fit into these categories.
The Datalist table lists the object name, the redshift (as compiled
from a catalog in the paper), data file (zipped fits), browse file
(pdf), and program name (linked to original proposal). All of these
give links as follows: Object to NED link on the object, FITS to
zipped binary table fits file, Figure to pdf format file, and Program
to abstract of original program leading to the observation.
The data files contain 4 vectors (wavelengths, fluxes, errors, and Data
Quality flags). A few details of the data that main interest some in
features of the data are as follows:
the data in the plots are applied in the browse plots but not the fits data,
for some objects wavelength overlap exists between spectra obtained with
different gratings; these are represented by a spectial DQ value in the data
and horizontal bars in the lower plot panels. In such cases the wavelength
binning region is smoothly interpolated across the region of overlap, and
for spectra obtained with the FOS blue detector the data vectors
are listed in order of decreasing wavelengths.
As an aid to the investigator, the positions and parent ion of a number
of candidate emission lines are annotated in the browser figures. These
have not always come out easily visible in the plots, so we
reproduce a listing
of the wavelengths and parent ions of these lines. In these plots
air wavelengths are used above 2000 Angstroms. The DQ plots also exhibit
the grating/camera configuration used for each wavelength region.