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Abstract In high-energy astrophysical processes involving compact objects, such as core-collapse supernovae or binary neutron star mergers, neutrinos play an important role in the synthesis of nuclides. Neutrinos in these environments can experience collective flavor oscillations driven by neutrino–neutrino interactions, including coherent forward scattering and incoherent (collisional) effects. Recently, there has been interest in exploring potential novel behaviors in collective oscillations of neutrinos by going beyond the one-particle effective or “mean-field” treatments. Here, we seek to explore implications of collective neutrino oscillations, in the mean-field treatment and beyond, for the nucleosynthesis yields in supernova environments with different astrophysical conditions and neutrino inputs. We find that collective oscillations can impact the operation of theνp-process andr-process nucleosynthesis in supernovae. The potential impact is particularly strong in high-entropy, proton-rich conditions, where we find that neutrino interactions can nudge an initialνp-process neutron-rich, resulting in a unique combination of proton-rich low-mass nuclei as well as neutron-rich high-mass nuclei. We describe this neutrino-induced neutron-capture process as the “νi-process.” In addition, nontrivial quantum correlations among neutrinos, if present significantly, could lead to different nuclide yields compared to the corresponding mean-field oscillation treatments, by virtue of modifying the evolution of the relevant one-body neutrino observables.
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This content will become publicly available on January 14, 2027
Proton-rich Production of Lanthanides: The vi Process
Abstract The astrophysical origin of the lanthanides is an open question in nuclear astrophysics. Besides the widely studieds,i, andrprocesses in moderately to strongly neutron-rich environments, an intriguing alternative site for lanthanide production could in fact be robustlyproton-richmatter outflows from core-collapse supernovae under specific conditions—in particular, high-entropy winds with enhanced neutrino luminosity and fast dynamical timescales. In this environment, excess protons present after charged-particle reactions have ceased can continue to be converted to neutrons by (anti)neutrino interactions, producing a neutron-capture reaction flow up toA ∼ 200. This scenario, christened theνiprocess in a recent paper, has previously been discussed as a possibility. Here, we examine the prospects for theνiprocess through the lenses of stellar abundance patterns, bolometric light curves, and galactic chemical evolution models, with a particular focus on hypernovae as candidate sites. We identify specific lanthanide signatures for which theνiprocess can provide a credible supplement to ther/iprocesses.
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- Award ID(s):
- 2411495
- PAR ID:
- 10659355
- Publisher / Repository:
- AAS
- Date Published:
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 997
- Issue:
- 1
- ISSN:
- 2041-8205
- Page Range / eLocation ID:
- L14
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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