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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:

  1. smoothing/trimming of the data in the plots are applied in the browse plots but not the fits data,
  2. 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
  3. 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.


Available Data and Line List