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Calibration Database System

There are also many model spectra of non-stellar objects available from CDBS. These are, according to their classification:

Brown dwarfs / substellar objects:

Digital form of the spectrum of Gliese 229B. This data is presented in the paper entitled "The Spectrum of Gliese 229B" by B. R. Oppenheimer, S. R. Kulkarni, K. Matthews and M. H. van Kerkwijk (1998, ApJ, in press). Please contact Ben R. Oppenheimer before using this data in any publication or presentation.

These spectra can be found in the non-stellar ftp site.

Nebulae representative models:

Note other nebulae with different excitation classes may have very different spectral characteristics.

These spectra can be found in the non-stellar ftp site.

Ellipitcal / Spiral / Starburst Galaxies:

These spectra can be found in the non-stellar ftp site.

[1] Coleman, Wu, Weedman, 1980, ApJS, 43, 393. Abstract: Ultraviolet observations of nearby galaxies with the ANS are used to derive ultraviolet spectra for different galaxy types. These spectra are used with existing visible spectrophotometry to calculate K-corrections, and to predict colors and magnitudes for various galaxy types as a function of redshifts, to z = 2. No evolutionary effects are considered. It appears that the first-ranked cluster galaxies on blue emulsions should be spirals for z greater than or approximately equal to 0.5.
[2] Coleman, Wu, Weedman 1980 templates recalibrated by Benitez et al. 2004, ApJS, 150, 1
[3] Starburst galaxies form Kinney et al. 1996 (ApJ, 467, 38) recalibrated by Benitez et al. 2004
[4] Young 5, 25 Myr old simple stellar populations with 0.4 times solar metallicity from Bruzual & Charlot 2003, MNRAS, 344, 1000
[5] Representative models

Starburst galaxies (Kinney models):

From Kinney et al. 1996, ApJ, 467, 38.

Template UV-Optical spectra for starburst galaxies, from a combination of IUE data and of optical data with an aperture size matched to the IUE. The templates of the starburst galaxies are built according to color excess. In order to make the templetes, all the spectra are shifted to the rest frame and corrected for the foreground Galactic extinction using the Seaton (1979) extinction curve. Within the starburst group, the UV-optical spectra are rescaled to a common flux value and are averaged, after weighting each spectrum by its SNR ratio to produce the final template.

These spectra can be found in the non-stellar ftp site.

BC03 models:

Bruzual and Charlot 2003 (MNRAS, 344, 1000) Tau models with solar metallicity, Tau = 0.6 Gyr, and exponentially decreasing star formation.

These spectra can be found in the non-stellar ftp site.

Quasars:

The QSO SDSS based spectra comes from http://iopscience.iop.org/1538-3881/122/2/549/fulltext/datafile1.txt from "Composite Quasar Spectra From the Sloan Digital Sky Survey" by Vanden Berk D.E. et al. 2001, AJ, 122, 549. Abstract excerpts: We have created a variety of composite quasar spectra using a homogeneous data set of over 2200 spectra from the SDSS. The input spectra cover an observed wavelength range of 3800 - 9200 A at a resolution of 1800. The median composite covers a rest wavelength range from 800 to 8555 A and reaches a peak signal-to-noise ratio of over 300 per 1 A resolution element in the rest frame. We have identified over 80 emission-line features in the spectrum.

The IRTF quasar is from Glikman E., Helfand D.J., White R.L. ApJ 2006, 640, 579. Abstract: We present a near-infrared quasar composite spectrum spanning the wavelength range 0.58-3.5 microns. The spectrum has been constructed from observations of 27 quasars obtained at the NASA IRTF telescope and satisfying the criteria K_s < 14.5 and M_i < -23; the redshift range is 0.118 < z < 0.418. The signal-to-noise ratio is moderate, reaching a maximum of 150 between 1.6 and 1.9 micron. While a power-law fit to the continuum of the composite spectrum requires two breaks, a single power-law slope of alpha = -0.92 plus a 1260 K blackbody provides an excellent description of the spectrum from H_alpha to 3.5 microns, strongly suggesting the presence of significant quantities of hot dust in this blue-selected quasar sample. We measure intensities and line widths for 10 lines, finding that the Paschen line ratios rule out case B recombination. We compute K-corrections for the J, H, K, and Spitzer 3.6 micron bands, which will be useful in analyzing observations of quasars up to z = 10.

These spectra can be found in the non-stellar ftp site.

Infrared Galaxies:

Examples of galaxy spectra are taken from the Spectral Atlas of Infrared Luminous Galaxies. This atlas contains a set of spectrum templates of nearby infrared-luminous galaxies covering the wavelength range 0.1 to 1000 microns. Data were collected from the NASA Extragalactic Database (NED), and included photometry from the U-band through the K-band in the near-infrared. Photometry from the Infrared Astronomical Satellite (IRAS) as well as spectra from the Spitzer/Infrared Spectrograph (Armus et al. 2004, 2007) have been incorporated.

The optical/NIR data were fitted using two stellar components (a young component and an evolved component) so that the U to K band fluxes of the galaxies are reproduced. The far-infrared spectral energy distribution (SED) was fitted using the dust continuum models in Chary & Elbaz (2001). The Spitzer mid-infrared spectra were scaled to agree with the IRAS flux densities. The one exception is the template of M82 which was reconstructed from ISO data (Chary & Elbaz 2001). The range of mid-infrared SEDs in these templates illustrate the strength of polycyclic aromatic hydrocarbon (PAH) features and silicate features which might be present in real galaxies. Specifically, the features occur at wavelengths (in microns) of:

3.3: PAH emission
6.2: PAH emission
7.7: PAH emission
8.6: PAH emission
9.7: Broad Silicate, typically in absorption; can be seen in emission in AGN                                                      
11.3: PAH emission
12.7: PAH emission
18: Broad Silicate, typically in absorption; can be seen in emission in AGN.

These SEDs do not yet incorporate results on these galaxies from GALEX, Planck, and Herschel.

Because the templates are constructed using a combination of real data and models, artificial discontinuities at certain wavelengths may be noticeable.

These spectra can be found in the non-stellar ftp site.