* Astronomy

Title: A barium-rich binary central star in Abell 70
Authors: Henri M. J. Boffin, B. Miszalski, D. J. Frew, A. Acker, J. Köppen, A. F. J. Moffat, Q. A. Parker

We have found the central star of Abell 70 (PN G038.1-25.4, hereafter A 70) to be a binary consisting of a G8 IV-V secondary and a hot white dwarf. The secondary shows enhanced Ba II and Sr II features, firmly classifying it as a barium star. The nebula is found to have Type-I chemical abundances with helium and nitrogen enrichment, which combined with future abundance studies of the central star, will establish A 70 as a unique laboratory for studying s-process AGB nucleosynthesis.

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