The primary reference for the Copernicus Spectral Atlas of Sirius
is Rogerson, J. B.,
The summary information that follows is taken from that reference.
The observations obtained to construct this atlas were obtained primarily
during the periods 1977 March 5-8, 1977 March 12-16, and 1977 March
18-April 5. There were several gaps in the coverage of this data; these
were filled in with observations obtained during the period 1981 February
8-9. A gap starting at 2292.7 Å was overlooked. The spectral atlas
covers wavelengths from 1649 Å to 3170 Å, with a spectral
resolution of 0.1 Å. The scans were made in the V1 detector. A
complete description of the Copernicus science instrument may be
found in Rogerson et al.(1973ApJ...181L..97R).
Wavelengths were corrected for Doppler shifts due to (a) the heliocentric
radial velocity of Sirius, (b) the Earth's heliocentric velocity in the
direction of Sirius, and (c) the component of the satellite geocentric
orbital velocity in the direction of Sirius. The counts from the source
were corrected for counts due to cosmic rays and trapped charge particles,
guiding errors and scattered light within the spectrometer. No correction
was made for the wavelength variations in the spectrometer sensitivity.
The atlas is a compilation of 36 separate scans of specific spectral
regions. There are a total of six files, numbered 2-7 (following the
original NSSDC file numbering scheme). File 2 contains the counts for the
vacuum spectrum; file 3 contains the normalizing continuum and scattered
light values for the vacuum spectrum; file 4 contains the line
identification table for the vacuum spectrum; file 5 contains the counts
for the air spectrum; file 6 contains the normalizing continuum and
scattered light values for the air spectrum; and file 7 contains the line
identification table for the air spectrum.