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Abstract While modeling the galactic chemical evolution (GCE) of stable elements provides insights to the formation history of the Galaxy and the relative contributions of nucleosynthesis sites, modeling the evolution of short-lived radioisotopes (SLRs) can provide supplementary timing information on recent nucleosynthesis. To study the evolution of SLRs, we need to understand their spatial distribution. Using a three-dimensional GCE model, we investigated the evolution of four SLRs:53Mn,60Fe,182Hf, and244Pu with the aim of explaining detections of recent (within the last ≈1–20 Myr) deposition of live53Mn,60Fe, and244Pu of extrasolar origin into deep-sea reservoirs. We find that core-collapse supernovae are the dominant propagation mechanism of SLRs in the Galaxy. This results in the simultaneous arrival of these four SLRs on Earth, although they could have been produced in different astrophysical sites, which can explain why live extrasolar53Mn,60Fe, and244Pu are found within the same, or similar, layers of deep-sea sediments. We predict that182Hf should also be found in such sediments at similar depths.
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Can We Draw Conclusions on Supernova Shock Wave Propagation Using Short‐Lived Radioactive Isotopes?
ABSTRACT We run a three‐dimensional Galactic chemical evolution (GCE) model to follow the propagation of53Mn (exclusively produced from type Ia supernovae, SNIa),60Fe (exclusively produced from core‐collapse supernovae, CCSNe),182Hf (exclusively produced from intermediate mass stars, IMSs), and244Pu (exclusively produced from neutron star mergers, NSMs). By comparing the predictions from our three‐dimensional GCE model to recent detections of53Mn,60Fe, and244Pu on the deep‐sea floor, we draw conclusions about their propagation in the interstellar medium.
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- Award ID(s):
- 1927130
- PAR ID:
- 10599878
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Astronomische Nachrichten
- Volume:
- 346
- Issue:
- 3-4
- ISSN:
- 0004-6337
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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