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Abundances of s-process elements in planetary nebulae: Br, Kr & Xe

Y. Zhang·R. Williams·E. Pellegrini·K. Cavagnolo·J. A. Baldwin·B. Sharpee·M. Phillips·X. -W. Liu
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Abstract

We identify emission lines of post-iron peak elements in very high signal-to-noise spectra of a sample of planetary nebulae. Analysis of lines from ions of Kr and Xe reveals enhancements in most of the PNe, in agreement with the theories of s-process in AGB star. Surprisingly, we did not detect lines from Br even though s-process calculations indicate that it should be produced with Kr at detectable levels.

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Y. Zhang, R. Williams, E. Pellegrini, K. Cavagnolo, J. A. Baldwin, B. Sharpee, M. Phillips, X. -W. Liu. 2006-05-06. Abundances of s-process elements in planetary nebulae: Br, Kr & Xe. https://doi.org/10.1017/s1743921306004182

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