PI: Joleen Carlberg, Carnegie Institution of Washington, email@example.com
Address: Department of Terrestrial Magnetism, 5241 Broad Branch Road, NW, Washington, DC 20015, USA
CoI: Katia Cunha, Observatorio Nacional
CoI: Verne Smith, NOAO
CoI: Jose Dias do Nascimento Jr, Univ. of Rio Grande do Norte
Title: Beryllium Abundances in Select Li-rich Red Giants as a Signature of Planet Engulfment
Abstract: We will measure Be abundance in a sample of Li-rich giants to look for Be-enrichment as a signature of planet engulfment. Standard stellar evolution predicts that first-ascent red giant stars will be Li-poor and Be-poor due to convective dilution. Therefore, the well known Li-rich red giants must have had their surface Li replenished either internally (through thermonuclear reactions) or externally (through planet engulfment). The nuclear pathway that results in ^7Li will not replenish the other diluted light elements (Be and B), whereas planet engulfment should replenish all of them. All of the selected stars have evidence for planet engulfment other than the enriched Li, the most common of which is enhanced rotational velocity. Unusually rapid rotation may itself be explained by the acquisition of an engulfed planet's orbital angular momentum. Past studies of similar intent have selected stars \it solely for Li-richness, and Be measurements have consequently been made only for the more ubiquitous slow rotators. Because we specifically select against stars for which Li-regeneration seems valid, we are well-positioned to successfully detect the planet engulfment signature of enriched Be.
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