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The Gamma Pegasi Spectral Atlas

[Gamma Pegasi Sample Spectrum]

The primary reference for the Copernicus Spectral Atlas of Gamma Pegasi is Rogerson, J. B., (1985ApJS...57..751R). The summary information that follows is taken from that reference.

The observations used to construct this atalas were obtained during four different periods: 1978 July 27, 1978 October 30-November 22, 1978 December 16-22, and 1979 December 10-17. The spectral atlas covers wavelengths from 969.9 Å to 1430.2 Å (second order) and 1417.0 Å to 1501.4 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 Gamma Peg, (b) the Earth's heliocentric velocity in the direction of Gamma Peg, and (c) the component of the satellite geocentric orbital velocity in the direction of Gamma Peg. 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.

Since this star is a Beta Cephei variable with a period of 0.1518 days and velocity amplitude of 5 km/s, an additional correction was made for the Beta Cephei type variations. This correction is described in detail in the text.

The atlas is a compilation of 22 separate scans of specific spectral regions. There are a total of two files relating to the Gamma Peg Spectral Atlas. File 1 is the 2nd order spectrum and file 2 is the first order spectrum.


gampeg1.fts  21699     6      969.932  1430.177   2nd order
gampeg2.fts   1609     5     1417.040  1501.398   1st order