The observability of magnetohydrodynamic supernovae and their remnants using MeV gamma lines

ORAL

Abstract

Magneto-rotational supernovae (MR-SNe) are rare, highly energetic explosions characterized by exceptionally strong magnetic fields. Although uncommon, they are promising candidates for enriching galaxies with heavy r-process elements. Due to their rapid and early mass ejection compared to typical core-collapse supernovae, MR-SNe can provide the neutron-rich conditions necessary for robust r-process nucleosynthesis. In this work, we simulate beta-decay gamma-ray emission from an MR-SN at various evolutionary stages, from early epochs to optically thin phases, using tracer data from the ejecta in conjunction with the PRISM nucleosynthesis network and the ENDF/B-VIII.0 nuclear database. Our results show that in supernova remnants, gamma-ray signatures of isotopes such as 126Sn (and its daughter 126Sb) would serve as a compelling indicator of an r-process-producing supernova. Furthermore, the neutron-rich environments conducive to the r-process may also enhance the synthesis of 60Fe, making the detection of 60Fe (or its decay product 60Co) an additional diagnostic of favorable conditions. We also present predictions for prompt gamma-ray emissions from a future Galactic MR-SN event and highlight isotopes such as 131I, 132I, 132Te, 125Sb, 106Rh, and 103Ru as promising candidates for detection with upcoming MeV gamma-ray observatories.

*This work was partially supported by the Office of Defense Nuclear Nonproliferation Research and Development (DNN R&D), National Nuclear Security Administration, U.S. Department of Energy (GCM, LZH, RS) under contract number LA22-ML-DE-FOA-2440. We acknowledge support from the U.S. Department of Energy contract Nos. DE-FG0202ER41216 (EG, GCM), DE-FG0295ER40934 (RS), and DE-SC00268442 (ENAF- GCM, EG, RS), as well as from the NSF (N3AS PFC) grant No. PHY-2020275 (GCM, KL, RS), and NSF grant AST 2205847 (IUR). KL, GCM and RS, thank the Institute for Nuclear Theory for its kind hospitality and stimulating research environment, U.S. Department of Energy grant No. DE-FG02- 00ER41132. This work benef ited from the travel support provided to GCM, KL, LZH, and RS from the National Science Foundation Grant No. OISE-1927130 (IReNA). M.R. acknowledges support from the grants FJC2021-046688-I and PID2021-127495NB-I00, funded by MCIN/AEI/10.13039/501100011033 and by the European Union "NextGenerationEU" as well as "ESF Investing in your future". Additionally, he acknowledges support from the Astrophysics and High Energy Physics program of the Generalitat Valenciana ASFAE/2022/026 funded by MCIN and the European Union NextGenerationEU (PRTR-C17.I1). The work of XW is supported by the National Key R&D Program of China (2021YFA0718500), the National Natural Science Foundation of China (Grant No. 12494574) and the Chinese Academy of Sciences (Grant No. E329A6M1).

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Publication: https://arxiv.org/abs/2506.14991

Presenters

  • Zhenghai Liu

    • North Carolina State University

Authors

  • Zhenghai Liu

    • North Carolina State University

  • Evan Grohs

    • North Carolina State University

  • Kelsey A Lund

    • University of California, Berkeley

  • Gail C McLaughlin

    • North Carolina State University

  • Moritz Reichert

    • Universitat de Valencia

  • Ian U Roederer

    • North Carolina State University

  • Rebecca A Surman

    • University of Notre Dame

  • Xilu Wang

    • Institute of High Energy Physics