More light on RV Tauri variables

نویسنده

  • S. C. Russell
چکیده

This study confirms the results of the preliminary study (Russell, 1997) indicating that RV Tau variables in globular clusters don’t show the kind of anomalous abundances seen in RV Tau variables observed in the field. By making comparisons with red giants in the same clusters, it has been possible, for the first time, to identify precisely how each element deviates from the normal abundance ratios of evolved giants. The apparent systematic deficiency in s-process elements reported for RVTau variables in the literature is not confirmed in the present study. Either the stars observed here are of such low metallicity, that what ever process causes s-process deficiencies in more metal rich field stars doesn’t operate; or the systematic deficiency in s-process elements is simply an illusion of small number statistics.

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تاریخ انتشار 1997