Title: Fine structure of the red giant clump from Hipparcos data, and distance determinations based on its mean magnitude
Abstract: The I-band brightness MI of clump stars is a possible distance indicator for stellar populations. Investigations have shown that MI is almost insensitive to the V−I colour within the clump. Based on this, it was assumed that MI was insensitive to age and composition of the stellar population and therefore an ideal standard candle, which could be calibrated with local clump stars whose absolute brightness is known from Hipparcos parallaxes. This resulted in a distance to the Large Magellanic Cloud about 15 per cent smaller than usually determined.In the present paper we show that with a population synthesis approach we can reproduce the constancy of MI with colour for the local Hipparcos clump sample. Nevertheless, MI is not a constant among different populations, but depends on metallicity. As a result, the calculated distance modulus to the LMC of 18.28 ± 0.14 mag is in better agreement with standard values. This resolves, at least partially, the controversial result obtained by the assumption of a universal value for MI.
Publication Year: 1998
Publication Date: 1998-11-01
Language: en
Type: article
Indexed In: ['crossref', 'datacite']
Access and Citation
Cited By Count: 98
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot