Carbon Deficiency in Externally-polluted White Dwarfs: Evidence for Accretion of Asteroids
نویسنده
چکیده
Existing determinations show that n(C)/n(Fe) is more than a factor of 10 below solar in the atmospheres of three white dwarfs that appear to be externallypolluted. These results are not easily explained if the stars have accreted interstellar matter, and we re-interpret these measurements as evidence that these stars have accreted asteroids with a chondritic composition. Subject headings: planetary systems – white dwarfs
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