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High signal-to-noise ratio — The spectroscopic key to Algol systems


The usefulness of high signal-to-noise-ratio spectra for both radial-velocity and abundance studies of Algol systems is emphasised. It is shown that division by a hot star is a worthwhile step in pursuit of this objective. A preliminary analysis of high signalto-noise-ratio, red and near-infrared, Reticon observations of R CMa shows that its primary has solar CNO abundances within the 0.3 dex observational error. The low-mass (0.17 m) secondary of this Algol system must have lost a large fraction of its original mass. Some of this material would have been extensively processed during the secondary's main-sequence lifetime and would therefore have had a highly non-solar CNO-abundance distribution. The lack of serious contamination of the primary's abundances is consistent with most, but not all, plausible mass-transfer scenarios.

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Tomkin, J. High signal-to-noise ratio — The spectroscopic key to Algol systems. Space Sci Rev 50, 245–255 (1989).

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  • Preliminary Analysis
  • Large Fraction
  • Observational Error
  • Original Mass
  • Abundance Study