Stellar origin of the ¹⁸²Hf cosmochronometer and the presolar history of solar system matter

Lugaro, Maria; Heger, Alexander; Osrin, Dean; Goriely, Stephane; Zuber, Kai; Karakas, Amanda I.; Gibson, Brad K.; Doherty, Carolyn L.; Lattanzio, John C.; Ott, Ulrich

Abstract

Among the short-lived radioactive nuclei inferred to be present in the early solar system via meteoritic analyses, there are several heavier than iron whose stellar origin has been poorly understood. In particular, the abundances inferred for ¹⁸²Hf (half-life = 8.9 million years) and ¹²⁹I (half-life = 15.7 million years) are in disagreement with each other if both nuclei are produced by the rapid neutron-capture process. Here, we demonstrate that contrary to previous assumption, the slow neutron-capture process in asymptotic giant branch stars produces ¹⁸²Hf. This has allowed us to date the last rapid and slow neutron-capture events that contaminated the solar system material at ∼100 million years and ∼30 million years, respectively, before the formation of the Sun.

Citation

Lugaro, M., Heger, A., Osrin, D., Goriely, S., Zuber, K., Karakas, A. I., …Ott, U. (2014). Stellar origin of the ¹⁸²Hf cosmochronometer and the presolar history of solar system matter. Science, 345(6197), 650-653. https://doi.org/10.1126/science.1253338

• Journal Article Type: Article
• Acceptance Date: Jun 16, 2014
• Online Publication Date: Aug 7, 2014
• Publication Date: Aug 8, 2014
• Deposit Date: Apr 13, 2016
• Publicly Available Date: Apr 13, 2016
• Journal: Science
• Print ISSN: 0036-8075
• Electronic ISSN: 1095-9203
• Publisher: American Association for the Advancement of Science
• Peer Reviewed: Peer Reviewed
• Volume: 345
• Issue: 6197
• Pages: 650-653
• DOI: https://doi.org/10.1126/science.1253338
• Keywords: Cosmochronometer
• Public URL: https://hull-repository.worktribe.com/output/435803
• Publisher URL: http://science.sciencemag.org/content/345/6197/650
• Additional Information: This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in Science on v.345 08 Aug 2014, DOI: 10.1126/science.1253338.