Astrophysics and Space Science

, Volume 76, Issue 2, pp 329–339 | Cite as

The helium content of the peculiar Oosterhoff type I globular cluster ω Centauri

  • Filippina Caputo
Article

Abstract

An investigation of the observational properties for RR Lyrae variables in the galactic globular cluster ω Centauri is reported. The results show that ω Centauri belongs to the Oosterhoff Group I, notwithstanding the large, Oo II-like value of the average of the periods of ab-type RR Lyrae. The helium content is derived for this cluster from the analysis of the variables in the (A-logTe) plane. It is shown that the helium abundance is very close to the value Y=0.30, about 0.05 larger than the value derived for the ‘normal’ Oo I globular cluster M3.

Keywords

Helium Globular Cluster Observational Property Helium Content Helium Abundance 

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Copyright information

© D. Reidel Publishing Co. 1981

Authors and Affiliations

  • Filippina Caputo
    • 1
  1. 1.Istituto Astrofisica SpazialeFrascatiItaly

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