Abstract
Some stars have outer layers which are sufficiently quiescent for diffusion to occur and to modify the relative abundances of the chemical elements. Levitation occurs when the forces due to radiation pressure are larger than those due to gravitation.
The paper describes some recent work on the calculation of the radiative forces using atomic data obtained in the course of the work of the Opacity Project.
Large abundance anomalies are observed for the HgMn stars, which lie on or close to the main sequence and have effective temperatures in the range 11000 to 15000 K. Some results are given for calculated abundances of elements of the iron group in the HgMn stars.
levitate:To rise or cause to rise and float in the air, usually attributed to supernatural intervention. (Collins Dictionary of the English Language)
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© 1996 Springer Science+Business Media Dordrecht
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Seaton, M.J. (1996). Levitation. In: Willis, A.J., Hartquist, T.W. (eds) Astrophysical and Laboratory Plasmas. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-0803-6_6
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DOI: https://doi.org/10.1007/978-94-017-0803-6_6
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