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The Tau Scorpii Spectral Atlas

[Tau Sco Sample Spectrum]

The primary reference for the Copernicus Spectral Atlas of Tau Scorpii is Rogerson, J. B. and Upson, Walter L., (1977ApJS...35...37R). The summary information that follows is taken from that reference.

The observations obtained to construct this atlas were obtained primarily during the periods between 1973 July 2 and August 27. The spectral atlas covers wavelengths from 948 Å to 1420.6 Å (second order) and 1418.2 Å to 1560.2 Å (first order), with a spectral resolution of 0.1 Å in first order and 0.05 Å in second order. The scans were made in the U1 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 Tau Sco, (b) the Earth's heliocentric velocity in the direction of Tau Sco, and (c) the component of the satellite geocentric orbital velocity in the direction of Tau Sco. 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 32 separate scans of specific spectral regions. There are a total of two files relating to the Tau Sco Spectral Atlas. File 1 is the 2nd order spectrum and file 2 is the first order spectrum.

ERRATUM: Note that there is a slight wavelength error in both file 2 and the published paper for wavelengths greater than 1499.9 Å. The corrected values are obtained using the relation

W(correct) = 1.0014523 * W(table) - 2.2656.


tausco1.fts   21780     7      948.735  1420.510   2nd order
tausco2.fts    2721     7     1418.187  1560.372   1st order