A Library of Integrated Spectra of
Galactic Globular Clusters

Ricardo P. Schiavon, James A. Rose, Stéphane Courteau & Lauren MacArthur


                                                                   47 Tuc: Courtesy of NOAO/AURA/NSF

We present a new library of integrated spectra of 40 Galactic globular clusters, obtained with the Blanco 4 m telescope and the R-C spectrographat the Cerro Tololo Interamerican Observatory.  The spectra cover the range ~ 3350 - 6430 Å with ~ 3.1 Å (FWHM) resolution. The spectroscopic observations and data reduction were designed to integrate the full projected area within the cluster core radii in order to properly sample the light from stars in all relevant evolutionary stages. The S/N values of the flux-calibrated spectra range from 50 to 240/Å at 4000 Å and from 125 to 500/Å at 5000 Å. The selected targets span a wide range of cluster parameters, including metallicity, horizontal-branch morphology, Galactic coordinates, Galactocentric distance, and concentration. The total sample is thus fairly representative of the entire Galactic globular cluster population and should be valuable for comparison with similar integrated spectra of unresolved stellar populations in remote systems. For most of the library clusters, our spectra can be coupled with deep color-magnitude diagrams and reliable metal abundances from the literature to enable the calibration of stellar population synthesis models.

The paper presenting the spectral library can be found here.

To access the spectral library, click here.