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Do dusty A stars exhibit accretion signatures in their photospheres?

Inga Kamp·Marc Hempel·Hartmut Holweger
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Abstract

We determined abundances of O, Ca, Fe, Ba and Y for a sample of dusty and dust-free A stars, taken from the list of Cheng et al. (1992). Five of the stars have an infrared-excess due to circumstellar dust. Ongoing accretion from their circumstellar surroundings might have modified the abundances in the photospheres of these stars, but our results clearly show, that there is no difference in the photospheric composition of the dusty and dust-free stars. Instead all of them show the typical diffusion pattern which diminishes towards larger rotational velocities.

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Inga Kamp, Marc Hempel, Hartmut Holweger. 2002-04-26. Do dusty A stars exhibit accretion signatures in their photospheres?. https://doi.org/10.1051/0004-6361%3A20020493

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