SN-1999aa data set

AJ 128, 3874 (2004), (astro-ph/0507288)

The archive (tar file) of the data set presented in the paper can be downloaded here.

The file name includes  the epoch with respect to B-band maximum light. Each file includes an ascii table with three columns: Wavelength (de-redshifted), Observed Flux, Statistical Error (Based on the optimal extraction algorithm).
Brief summary of the  data reduction steps:
SN~1999aa's host galaxy, NGC~2595, is  at redshift z= 0.0146.  All the data presented in the archive were de-reshifted using this redshift value.

The data set consists of 25 optical spectra, obtained using five different instruments,  extending from day -11 to day +58 (in this archive all phases are expressed with respect to B-band maximum). In most cases, the spectra were acquired using different instrumental settings for the blue and red parts of the spectrum to avoid possible second-order contamination. Hence, the 25 fully reduced spectra are the combinations of both blue and red parts. Spectra were taken with the slit rotated to a position angle close to the parallactic angle at the mid-point of each exposure.

The data were reduced using standard IRAF routines. The two-dimensional images were bias-subtracted and flat-fielded. In most of the cases, the observations were split into multiple exposures in order to allow elimination of cosmic rays from the final spectrum.  The background sky and the underlying host galaxy were fitted, subtracted, and extracted for systematics checks of the wavelength calibration. The supernova spectrum was extracted using the  variance weighted optimal aperture extraction method.  Wavelength and flux calibration were applied to the one-dimensional extracted spectra using arc and standard star observations taken with the same instrumental setting and during the same night as the science observations. The accuracy of the wavelength calibration was checked against the extracted sky spectra and generally found to agree to within 2~\AA. Mean smoothed atmospheric extinction corrections for each observatory were applied. No correction was yet been made for telluric features or residual fringing. Synthetic spectrophotometry was computed to check the overall accuracy of the flux calibration against publicly available photometric data and found to agree within the quoted statistical uncertainties.

The Galactic reddening in the direction of  SN 1999aa is E(B-V) = 0.04 mag. The correction for Galactic extinction was performed using the standard procedure (Schlegel, et al.,  ApJ 500, 525 (1998)) assuming R_V = 3.1.

No host galaxy reddening correction was applied.
Citation Requirement:
Any publication that makes use of this data should cite: G. Garvini, AJ 128, 3874 (2004). Data made available by the Supernova Cosmology Project.

For  further information please contact Gabriele Garavini.

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