Comprehensive Analysis of the Neutrino Process in Core-collapsing Supernovae

Abstract

We investigate the neutrino flavor change effects due to neutrino self-interaction and shock wave propagation, as well as the matter effects on the neutrino process in core-collapsing supernovae (CCSNe). For the hydrodynamics, we use two models: a simple thermal bomb model and a specified hydrodynamics model for SN1987A. For the presupernova model, we take an updated model, adjusted to explain SN1987A, which employs recent developments in the (n, γ) reaction rates for nuclei near the stability line (A ∼ 100). As for the neutrino luminosity, we adopt two different models: equivalent neutrino luminosity and nonequivalent luminosity models. The latter is taken from a synthetic analysis of CCSN simulation data, which quantitatively presented the results obtained by various neutrino transport models. Relevant neutrino-induced reaction rates are calculated using a shell model for light nuclei and a quasiparticle random phase approximation model for heavy nuclei. For each model, we present abundances of the light nuclei (7Li, 7Be, 11B, and 11C) and the heavy nuclei (92Nb, 98Tc, 138La, and 180Ta) produced by the neutrino process. The light nuclei abundances turn out to be sensitive to the Mikheyev–Smirnov–Wolfenstein (MSW) region around O-Ne-Mg layer while the heavy nuclei are mainly produced prior to the MSW region. Through detailed analyses, we find that neutrino self-interaction becomes a key ingredient, in addition to the MSW effect, for understanding the neutrino process and the relevant nuclear abundances. The normal mass hierarchy is shown to be more compatible with the meteorite data. The main nuclear reactions for each nucleus are also investigated in detail.

Noniterative finite amplitude methods for giant resonances and the application to the neutron radiative capture cross sections

“…Since the production of large amounts of unstable nuclei, the calculated neutron capture cross sections are essential to the rapid neutron capture process (r-process) inside core-collapse supernovae and neutron-star mergers that can synthesize half of the heavy elements on the periodic table [6]. The capture reaction is also important for the neutrino-induced nucleosynthesis in core-collapse supernovae [7][8][9][10].…”

Revisiting the Gamow Factor Reactions on Light Nuclei

“…One of the ultimate goals of nuclear astrophysics is to elucidate the origin of elements in the universe. For this purpose, astrophysical processes such as r−, p−, and s−processes [1][2][3][4][5] have been well established, and recently, the rp− [6] and ν−induced processes [7][8][9][10] have been developed to supplement the conventional astrophysical processes. Such studies on nucleosynthesis are commonly evaluated by the network calculation, in which thermonuclear reaction rate plays a crucial role as the main building block.…”

Reinvestigating the Gamow Factor of Reactions on Light Nuclei

“…One of the ultimate goals of nuclear astrophysics is to elucidate the origin of the elements in the Universe. For this purpose, astrophysical processes such as r-, p-, and s-processes (Burbidge et al 1957;Kappeler et al 1989;Meyer 1994;Arnould et al 2007;Thielemann et al 2011) have been well established, and recently, the rp- (Schatz et al 1998) and νinduced processes (Woosley et al 1990;Fröhlich et al 2006;Kusakabe et al 2019;Ko et al 2022) have been developed to supplement the conventional astrophysical processes. Such studies on nucleosynthesis are commonly evaluated by network calculations, in which thermonuclear reaction rates play a crucial role as the main building blocks.…”