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arXiv · astro-ph/0102216

Analysis of Stars Common to the IRAS and HIPPARCOS Surveys

T. G. Knauer·Z. Ivezic·G. R. Knapp
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Abstract

For about 11,000 stars observed in the HIPPARCOS Survey and detected by IRAS we calculate bolometric luminosities by integrating their spectral energy distributions from the B band to far-IR wavelengths. We present an analysis of the dependence of dust emission on spectral type and correlations between the luminosity and dust emission for about 1000 sources with the best data (parallax error less than 30%, error in luminosity of about 50% or better). This subsample includes stars of all spectral types and is dominated by K and M giants. We use the IRAS [25]-[12] color to select stars with emission from circumstellar dust and show that they are found throughout the Hertzsprung-Russell diagram, including on the main sequence. Clear evidence is found that M giants with dust emission have luminosities about 3 times larger (about 3000 Lsun) than their counterparts without dust, and that mass loss on the asymptotic giant branch for both M and C stars requires a minimum luminosity of order 2000 Lsun. Above this threshold the mass-loss rate seems to be independent of, or only weakly dependent on, luminosity. We also show that the mass-loss rate for these stars is larger than the core mass growth rate, indicating that their evolution is dominated by mass loss.

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T. G. Knauer, Z. Ivezic, G. R. Knapp. 2001-02-12. Analysis of Stars Common to the IRAS and HIPPARCOS Surveys. https://doi.org/10.1086/320584

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