O5 through L3 empirical stellar spectra from SDSS

The templates cover spectral types O5 through L3, are binned by metallicity from -2.0dex through +1.0dex, and are separated into main-sequence (dwarf) stars and giant stars. With recently developed M dwarf metallicity indicators, we are able to extend the metallicity bins down through the spectral subtype M8, making this the first empirical library with this degree of temperature and metallicity coverage.

The wavelength coverage for the templates is from 3650 to 10200{AA} at a resolution of better than R~2000. Using the templates, we identify trends in color space with metallicity and surface gravity, which will be useful for analyzing large data sets from upcoming missions like the Large Synoptic Survey Telescope. Along with the templates, we are releasing a code for automatically (and/or visually) identifying the spectral type and metallicity of a star.