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Access to the AGN and Quasars Atlas files

The Active Galactic Nuclei and Quasars Atlas contains a few spectral AGN's templates, ranging from LINER to Seyfert galaxies, as well as bright QSOs. Download individial templets in the AGN ATLAS area.

The atlas contains a few spectral templates from AGNs covering the ultraviolet to the near-infrared spectral range (see Table 1 for spectral coverage). The LINER and Seyfert 2 templates have been obtained with the large aperture (10" by 20") and low-resolution spectrographs of the IUE satellite. The optical spectra were obtained through a long slit with a 10" width. From this, a window 20" long was extracted to match the IUE aperture (Calzetti 1995, private communication). The flux of the LINER and Seyfert2 templates is normalized to a Johnson visual magnitude of 12.5 (STMAG).

The Seyfert1 template consists of a UV spectrum obtained with the IUE low-resolution spectrograph and a ground-based optical spectrum. The bright QSO template is a composite spectrum from the Large Bright Quasar Survey of Francie and collaborators (1991). The Seyfert1 and QSO spectral templates are normalized to a Johnson blue magnitude of 12.5 (STMAG).

The NGC 1068 template is a composite spectrum. The continuum contains the nebular, stellar, and power-law contributions. The observed fluxes and FWHM of the UV, optical and near-IR emission lines are also incorporated into the template (J.R. Walsh, private communication). For more details read the header of the  FITS file.

Details about how each template was constructed can be found in the headers of the FITS files, or the references given above.

Table 1. List of Templates in the AGN Atlas

File Name

Spectral coverage (Angstroms)

Comments
liner_template  1235 - 7550 spectrum of M81
seyfert2_template 1235 - 9945 average of various spectra
seyfert1_template 1132 - 7078 spectrum of NGC 5548
qso_template 800 - 6000 average of various spectra
gc1068_template 1000 - 11000 model: lines + cont

References:

Francis et al. 1991, ApJ 373, 465.

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