A Complete Atlas of Recalibrated Hubble Space Telescope Faint Object Spectrograph Spectra of Active Galactic Nuclei and Quasars. I. Pre‐COSTAR Spectra

Abstract

We have recalibrated all nonpolarimetric, pre-COSTAR, archival Hubble Space Telescope Faint Object Spectrograph UV and optical spectrophotometry of active galaxies and quasars in order to extract uniformly calibrated spectrophotometric data for further detailed scientific investigations. The raw archival spectra have been recalibrated using the latest algorithms and calibration data. Spectral data contaminated by intermittent noisy diodes and cosmic-ray events have been identified manually and eliminated. Wherever possible we have combined multiple observations of the same source to produce a single spectrum per object with the highest possible signal-to-noise ratio and covering the widest wavelength range, scaling the individual data sets to the same photometric scale where necessary. Detailed quality assurance has been performed to ensure that the merged object spectra are of the highest quality consistent with the limitations of the individual data sets and calibrations. The recalibrated, merged object spectra are available in electronic form. We use this data set to present statistics of the photometric accuracy in the wavelength overlap regions for observations spanning multiple gratings.