129I and 247Cm in meteorites constrain the last astrophysical source of solar r-process elements

Benoit Côté; Marius Eichler; Andrés Yagüe López; Nicole Vassh; Matthew R Mumpower; Blanka Világos; Benjámin Soós; Almudena Arcones; Trevor M Sprouse; Rebecca Surman; Marco Pignatari; Mária K Pető; Benjamin Wehmeyer; Thomas Rauscher; Maria Lugaro

doi:10.1126/science.aba1111

¹²⁹I and ²⁴⁷Cm in meteorites constrain the last astrophysical source of solar r-process elements

Science. 2021 Feb 26;371(6532):945-948. doi: 10.1126/science.aba1111.

Authors

Benoit Côté^{1

2

3}, Marius Eichler⁴, Andrés Yagüe López⁵, Nicole Vassh⁶, Matthew R Mumpower^{7

8}, Blanka Világos^{5

2}, Benjámin Soós^{5

2}, Almudena Arcones^{4

9}, Trevor M Sprouse^{6

7}, Rebecca Surman⁶, Marco Pignatari^{10

5}, Mária K Pető⁵, Benjamin Wehmeyer^{5

11}, Thomas Rauscher^{11

12}, Maria Lugaro^{5

2

13}

Affiliations

¹ Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary. benoit.cote@csfk.org.
² Institute of Physics, Eötvös Loránd University, 1117 Budapest, Hungary.
³ National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA.
⁴ Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany.
⁵ Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary.
⁶ Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA.
⁷ Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
⁸ Center for Theoretical Astrophysics, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
⁹ GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany.
¹⁰ E.A. Milne Centre for Astrophysics, University of Hull, Hull HU6 7RX, UK.
¹¹ Centre for Astrophysics Research, University of Hertfordshire, Hatfield AL10 9AB, UK.
¹² Department of Physics, University of Basel, 4056 Basel, Switzerland.
¹³ Monash Centre for Astrophysics, School of Physics and Astronomy, Monash University, Clayton, VIC 3800, Australia.

PMID: 33632846
DOI: 10.1126/science.aba1111

Abstract

The composition of the early Solar System can be inferred from meteorites. Many elements heavier than iron were formed by the rapid neutron capture process (r-process), but the astrophysical sources where this occurred remain poorly understood. We demonstrate that the near-identical half-lives [Formula: see text] of the radioactive r-process nuclei iodine-129 and curium-247 preserve their ratio, irrespective of the time between production and incorporation into the Solar System. We constrain the last r-process source by comparing the measured meteoritic ratio ¹²⁹I/²⁴⁷Cm = 438 ± 184 with nucleosynthesis calculations based on neutron star merger and magneto-rotational supernova simulations. Moderately neutron-rich conditions, often found in merger disk ejecta simulations, are most consistent with the meteoritic value. Uncertain nuclear physics data limit our confidence in this conclusion.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.
Research Support, Non-U.S. Gov't