This set of files correspond to the high-redshift Type Ia supernova spectra taken with VLT+FORS1 for the ESSENCE Team (ESO proposal 170.A-0519; PI: Bruno Leibundgut), presented in Matheson et al. 2005 (astro-ph/0411357).

Examples of VLT spectroscopy of distant SNe Ia (extracted from Matheson et al. 2005)

The r.FORS1* files are the reduced 2D spectra (overscan and bias corrected; flat-fielded; wavelength calibrated), whilst the r.onedspec.FORS1* files are the corresponding flux- and wavelength-calibrated 1D spectra, extracted using the 2D restoration algorithm presented in Blondin et al. 2005. Note that the 1D spectra have not been dereddened or deredshifted. Detailed information on the implementation of the spectral extraction is available at Stephane Blondin's Web site. A detailed identification table can be found here.

You can also download the complete data package from the ESO Archive.

The ESSENCE Web page gives a detailed description of the project and the observations we attempt to determine whether the universe is dominated by the cosmological constant or a decaying particle field.