Pith. sign in

REVIEW 3 major objections 4 minor 111 references

Comparative Testing of Subgrid Models for Fast Neutrino Flavor Conversions in Core-collapse Supernova Simulations

T0 review · 3 major / 4 minor · reviewed 2026-08-07 · deepseek-v4-flash

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗

Pith's one-line read This paper claims that the standard three-species treatment of neutrino flavor conversion in core-collapse supernova simulations overestimates the conversion of electron neutrinos and antineutrinos, and that a four-species treatment is…

desk verdict A careful pilot comparison of FFC subgrid recipes in a dynamical CCSN simulation; the 4-species recommendation is plausible but rests on an unvalidated closure. read the letter →

arxiv 2506.07017 v2 pith:XYJ6IA5W submitted 2025-06-08 astro-ph.HE

Ryuichiro Akaho , Hiroki Nagakura , Shoichi Yamada This is my paper
classification astro-ph.HE
keywords fastflavorconversioncore-collapsesupernovaeneutrinotransportsubgridmodelBhatnagar-Gross-KrookELN-XLNcrossingsequipartitionheating
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

This paper tests how to include fast flavor conversions (FFC), the rapid collective neutrino flavor oscillations triggered by neutrino-neutrino self-interactions, in core-collapse supernova simulations. It finds that the common three-species assumption, which treats muon and tau neutrinos as identical to their antineutrinos, overestimates the conversion of electron neutrinos and antineutrinos and gives a qualitatively different flavor evolution from a four-species treatment. It also finds that a simple density-threshold equipartition recipe works for outgoing neutrinos but fails for ingoing ones, and that a semi-implicit time integration is the most robust way to couple the subgrid conversion term to Boltzmann transport. If correct, the results imply that earlier three-species subgrid studies misestimate flavor-converted neutrino spectra, heating rates, and shock dynamics, and that future simulations should carry four distinct neutrino species.

What carries the argument

The central object is the Bhatnagar-Gross-Krook (BGK) subgrid model, a relaxation-time approximation that drives the distribution functions toward an asymptotic post-conversion state on a timescale $\tau_{\rm as}$. The asymptotic state is built from the survival probability $\eta$ derived from the ELN-XLN crossing amplitudes $A$ and $B$, with $\eta$ chosen angle-by-angle to eliminate the smaller crossing and conserve neutrino number; the relaxation time is $\tau_{\rm as} = 2\pi/\sqrt{AB}$, motivated by the two-beam model. The paper compares this four-species closure, a three-species variant that forces $\nu_x = \bar\nu_x$ and zero heavy-lepton number, and a density-threshold flavor equipartition recipe, within an operator-split Boltzmann transport solver.

What would settle it

Run a quantum kinetic transport simulation on the same angle-averaged 2D snapshot (taken 270 ms after bounce) and compare the post-conversion $\nu_e$ and $\bar\nu_e$ spectra, the surviving ELN-XLN structure, and the relaxation timescale with the four-species BGK predictions; significant disagreement in the asymptotic spectra or in crossing elimination would show that the closure in Eqs. (17)-(20) is not the correct endpoint.

Watch

Extended reading notes

Core claim

The paper establishes that the choice of subgrid prescription materially changes both the flavor evolution and its hydrodynamic consequences in spherically symmetric Boltzmann neutrino radiation hydrodynamics. In the four-species Bhatnagar-Gross-Krook (BGK) model, FFC is driven by ELN-XLN crossings and relaxes toward an asymptotic state that distinguishes $\nu_x$ from $\bar\nu_x$; the three-species models, which erase only ELN crossings, develop earlier and persistently higher growth rates, leading to over-conversion of $\nu_e$ and $\bar\nu_e$. In the lower-$Y_e$ model, all mixing schemes reduce the neutrino heating rate and shrink the shock compared with no FFC, consistent with quantum kinetic transport studies, and the emitted luminosities and mean energies of $\nu_x$ and $\bar\nu_x$ differ noticeably in the four-species case. The paper concludes that the four-species treatment should be used to capture FFC effects accurately.

Load-bearing premise

The comparison assumes that the four-species asymptotic state defined by Eqs. (17)-(20) is the true endpoint of fast flavor conversion; the paper does not validate this closure against a quantum kinetic simulation on the same initial data, so the three-versus-four species contrast shows that the prescriptions differ even if it does not independently prove which is more accurate.

Editorial extensions

If this is right

  • If the four-species treatment is correct, previous three-species subgrid simulations overestimate how much electron neutrinos and antineutrinos are converted, so their flavor-converted spectra and luminosities are distorted.
  • Semi-implicit time stepping with a maximum step near $10^{-8}$ s resolves the first appearance of fast flavor instability; explicit methods overconvert and implicit methods violate lepton number conservation at larger steps.
  • Density-threshold equipartition recipes are acceptable for outgoing neutrinos but fail for ingoing neutrinos, and the error feeds back into matter profiles and emission properties once the hydrodynamics responds.
  • Fast flavor conversion lowers neutrino heating rates and shrinks the shock in the lower-$Y_e$ model, so FFC is not neutral for explosion dynamics in lepton-asymmetric situations.
  • In four-species models $\nu_x$ and $\bar\nu_x$ have measurably different luminosities and mean energies, so they should be transported and reported separately.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • A direct consequence the paper leaves implicit: if three-species subgrid results have been used to interpret observed supernova neutrino signals, those interpretations may need revisiting with four-species transport once multidimensional models are available.
  • The semi-implicit time-step requirement ($\Delta t \lesssim 0.01\tau_{\rm as}$ to resolve the onset) suggests that adaptive time stepping tied to the crossing growth rate will be needed in multidimensional runs to keep the onset of conversion from being numerically triggered.
  • The strong dependence on ingoing neutrinos in the lower-$Y_e$ model indicates that moment-based transport closures, which approximate the angular distribution, may not provide enough information for a four-species BGK subgrid, favoring multi-angle or Boltzmann-like transport.
  • A natural testable extension is to validate the asymptotic-state closure in Eqs. (17)-(20) against a quantum kinetic simulation on the same initial data, since the paper labels that as future work rather than as an established result.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 4 minor

Summary. The paper presents spherically symmetric general-relativistic Boltzmann neutrino radiation hydrodynamics simulations with Bhatnagar-Gross-Krook (BGK) subgrid models for fast flavor conversions (FFC), and systematically compares numerical and physical modeling choices. It first studies explicit, semi-implicit, and implicit time integration of the subgrid term, concluding that the semi-implicit method is preferable and that a time step cap around 10^-8 s is needed to resolve the onset of flavor instability. It then compares three FFC prescriptions: a 4-species BGK model based on erasing ELN-XLN crossings, a 3-species BGK model with nu_x = anti-nu_x, and a simple flavor-equipartition model with a baryon density threshold. The central findings are that the equipartition condition works reasonably for outgoing neutrinos but deviates for ingoing neutrinos, that 3-species models behave differently from 4-species models and tend to over-convert electron-type neutrinos, and that FFC lowers neutrino heating rates and shock radii in the lower-Ye model. The paper is framed as a pilot study for future multidimensional simulations.

Significance. If the underlying asymptotic closure for fast flavor conversion is reliable, this paper would be a valuable systematic comparison of subgrid prescriptions in a self-consistent Boltzmann transport setting. The time-integration study is well executed and provides concrete practical guidance, including the semi-implicit choice and the time-step cap. The comparison of angle-dependent survival probability against density-threshold equipartition, and of 3-species against 4-species treatments, addresses questions actively debated in the CCSN community. The manuscript is transparent about its limitations, including spherical symmetry, the neglect of collisional flavor instabilities, and the artificiality of the lower-Ye model. The main result of the paper, however, is the claim that 3-species models overestimate flavor conversion and that 4-species treatments are needed for accuracy; this claim depends entirely on the imported 4-species BGK asymptotic closure, which is not validated against a quantum kinetic baseline in this work.

major comments (3)
  1. [Sec. II B 1, Eqs. (17)-(27)] The 4-species asymptotic closure, Eqs. (17)-(20), with the survival probability eta computed from the energy-integrated crossing amplitudes A and B in Eqs. (21)-(26) and applied energy-independently, is imported from prior work (Zaizen and Nagakura 2023; Nagakura et al. 2024) and is not validated in this paper against a quantum kinetic simulation on the same initial data. The paper's central conclusion that 3-species models overestimate conversion and that 4-species treatment is required is only as strong as this closure. If the true endpoint of fast flavor conversion is not the one assumed, for example if ELN-XLN crossings are not fully erased or if the nu_x - anti-nu_x splitting differs, then Figs. 5-6 and 11-12 demonstrate only that the 3-species and 4-species prescriptions differ, not that either is more accurate. I ask the authors to add a benchmark test of Eqs. (17)-(20) against a quantum kinetic simulation initialized with the same distributions, or to explicitly reframe the conclusions as a comparison between prescriptions rather than a statement of accuracy.
  2. [Sec. II B 3] The density threshold rho = 10^11 g cm^-3 used in the 3sp-rho11 model is calibrated to the fiducial model, as stated in the text: 'because our model employed in this paper shows the appearance of FFI at rho less than or similar to 10^11 g cm^-3 (see Fig. 1)'. This calibrated threshold is then applied to the lower-Ye model, in which the no-oscillation FFI region has a different structure, including an extended deep-core region and a gap between 10^12 and 10^13 g cm^-3 (Fig. 8). The comparison of 3sp-rho11 against the BGK models in the lower-Ye case is therefore sensitive to a parameter chosen from a different model. A sensitivity study over threshold values, or a self-consistent crossing-based trigger, is needed before drawing conclusions about the failure of the equipartition approach in that regime.
  3. [Sec. II B 2, Eqs. (28)-(30)] The observed difference between 3-species and 4-species models is partly built into the definitions: 3spBGK imposes f_nu_x = f_anti-nu_x by construction, which sets XLN = 0 and violates lepton number conservation, whereas 4spBGK explicitly allows nu_x and anti-nu_x to differ. Consequently, observing a difference between nu_x and anti-nu_x in 4spBGK is expected rather than an empirical discovery. The manuscript should state this more prominently and quantify the practical significance, for example by reporting the magnitude of the generated XLN relative to the ELN in the 4spBGK runs. Without such a measure, the conclusion in Sec. VI that '4-species assumption should be used to accurately capture FFC effects' rests on a definitional difference combined with the unvalidated asymptotic closure.
minor comments (4)
  1. [Sec. II A and Sec. II B] There are small typographical errors: 'Code verification testes' should be 'Code verification tests', and the section heading 'Subgrid Model for F ast Flavor Conversion' contains a stray space.
  2. [Sec. III B] The time-integration comparison is convincing, but the text states that all production runs use a maximum time step of 10^-8 s; a brief summary of the computational cost at this time step would be useful for readers planning similar simulations.
  3. [Sec. IV, Fig. 5] The paper uses a 10-point angular grid, which is coarse for detecting angular crossings in fast flavor contexts. A short angle-convergence test, for instance comparing 10 versus 20 or 30 angle bins for the quasi-steady growth rates in Fig. 5, would strengthen confidence that the crossing amplitudes A and B are resolved.
  4. [Sec. V C] In the fiducial model, the statement that 'the effect of FFC on the PNS profile is anticipated to be more pronounced if FFC persists for a longer duration' is speculative; it would be better marked as an expectation rather than a finding.

Circularity Check

2 steps flagged · score 6.0 of 10

The 4-species BGK asymptotic closure is taken from self-cited prior work, and the observed νx–ν̄x difference plus the '3-species overestimates' conclusion follow from that closure by construction, so the central recommendation is only as strong as the unvalidated ansatz.

  1. self definitional [Abstract; Sec. II.B.1, Eqs. (19)-(20)]
    "In 4-species models, we commonly observe noticeable differences between νx and ¯νx, highlighting the limitation in 3-species treatments to study impacts of flavor conversion on neutrino signals."

    Equations (19) and (20) imply f_x^as − f̄_x^as = (1−η)/2 (f_e − f̄_e) + (1+η)/2 (f_x − f̄_x). Starting from a state with f_x = f̄_x, every electron-type asymmetry f_e − f̄_e is translated by the closure into a νx/ν̄x asymmetry. The 3-species model (Eqs. 28–30) is the same closure with f_x = f̄_x imposed. Therefore the reported 'noticeable differences between νx and ν̄x' are not an independent prediction but an algebraic consequence of the 4-species ansatz. Citing this difference as evidence that 3-species treatments are inadequate is circular unless the 4-species asymptotic closure itself has been validated against quantum-kinetic simulations, which this paper does not do.

  2. ansatz smuggled in via citation [Sec. II.B.1 and Sec. VI]
    "This model assumes that FFC occurs in a way to smear out ELN-XLN crossings [22]. The asymptotic states of the distribution functions f as are written as ... The relaxation time is estimated as τas ≡ 2π/√AB. This formula was motivated by two-beam model ... Overall trend is that the 3-species assumption tends to overestimate the conversion of νe and ¯νe ... implying that 4-species assumption should be used to accurately capture FFC effects."

    The paper's main conclusion is a comparison between 3spBGK and 4spBGK, but both models use endpoints determined by the same BGK framework. The 4spBGK endpoint (Eqs. 17–20) and the growth-rate estimate (Eq. 27) are imported from prior work by the present authors (Refs. [22], [23], [29]–[31], [34]) and are not validated here against a quantum-kinetic simulation on the same initial data. The cited Ref. [22] is itself a proposed 'simple method' (an ansatz) for asymptotic states, so citing it does not provide external grounding.

full rationale

We identify two linked circularities. First, the 4spBGK asymptotic-state formulas (Eqs. 17–20) are constructed so that any electron-neutrino asymmetry is converted into a νx/ν̄x difference; the paper then presents such differences as evidence for the inadequacy of 3-species models. Second, the 4-species closure, which is the yardstick for the 'overestimate' claim, comes from self-cited prior work (Zaizen & Nagakura 2023; Nagakura et al. 2024) and is not tested against QKE in this paper; the cited source is itself an ansatz ('simple method'). The paper does contain genuinely independent components: the time-integration tests (Sec. III), the lower-Ye sensitivity study, the comparison with the density-threshold equipartition prescription, and the CFI growth-rate comparison (Fig. 13). These parts are not circular. However, the headline recommendation that 4-species treatment is needed to 'accurately capture FFC effects' is only as strong as the assumed 4spBGK endpoint, and the supporting νx/ν̄x differences are baked into the closure. We therefore assign a partial-circularity score of 6, not higher, because the central dynamical results (heating-rate suppression, shock-radius reduction, and the 3spρ11/3spBGK agreement for outgoing neutrinos) are substantive numerical outputs rather than pure tautologies.

Assumptions & free parameters 5 free parameters · 6 assumptions · 0 invented entities

The central results depend on the BGK closure and on model choices (density threshold, constant relaxation time, lower-Ye initial condition). No new physical entities are introduced; the 'species' are standard neutrino flavors with a modeling choice for heavy-lepton degeneracy. The main assumption carried from prior work is the asymptotic-state formula.

free parameters (5)
  • Density threshold for 3sp-rho11 equipartition = 10^11 g cm^-3
    Chosen because FFI appears at rho < 10^11 g cm^-3 in the fiducial model (Sec. II B 3, Fig. 1); this calibrates the simplified equipartition model to the test case.
  • Constant relaxation time for 3sp-rho11 = 10^-7 s
    Set to imitate previous approximate transport studies (Ehring et al. 2023; Qiu et al. 2025), not derived from the local FFI growth rate in this run.
  • Time step cap for production runs = 10^-8 s
    Selected from convergence tests in Sec. III B; larger time steps overshoot the onset of FFC. This is a numerical control parameter, not a physics input.
  • Ye reduction in lower-Ye model = 10% below fiducial Ye
    Artificially lowered to mimic lepton-number asymmetries such as LESA or PNS kicks; acknowledged as artificial in Sec. II C 3.
  • Momentum-space angular grid size = 10 zenith angles
    Angular resolution in momentum space is fixed at 10 points, coarser than the roughly 100 points recommended for direct QKE simulations; this may affect crossing detection.
assumptions (6)
  • domain assumption FFI existence is equivalent to angular crossings of ELN-XLN (or ELN) in momentum space.
    Used in Sec. II B to define A and B and to decide where flavor conversion occurs; follows from Morinaga (2022) and Dasgupta (2022) but is not derived in this paper.
  • domain assumption The BGK asymptotic states f_as in Eqs. (17)-(20) describe the end state of fast flavor conversion.
    The entire subgrid model relies on this prior prescription (Zaizen and Nagakura 2023; Nagakura et al. 2024); this paper tests consequences but does not re-derive or validate it against QKE.
  • domain assumption The relaxation time tau_as = 2*pi/sqrt(A*B) from the two-beam model approximates the FFC growth rate.
    Used in Eq. (27) to set the BGK timescale; it is a phenomenological choice from previous post-processing studies, not fitted here but also not justified from first principles.
  • domain assumption A spherically symmetric simulation initialized from an angle-averaged 2D CCSN snapshot captures the relevant FFI dynamics.
    The authors note that spherically symmetric CCSN models suppress FFI, so they angle-average a 2D snapshot (Sec. II C). The validity of this dimensional reduction for FFC is not demonstrated.
  • domain assumption The 3-species model with nu_x = anti-nu_x implies XLN = 0 and lepton number violation.
    Explicitly stated in Sec. II B 2; this is by construction and drives the qualitative difference between 3-species and 4-species models.
  • domain assumption BGK relaxation is an adequate surrogate for quantum kinetic evolution over the simulation duration.
    The paper relies on the semi-implicit BGK method's prior agreement with QKE (Nagakura et al. 2024) rather than performing a QKE comparison here.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Comparative Testing of Subgrid Models for Fast Neutrino Flavor Conversions in Core-collapse Supernova Simulations." pith.science (2026). https://pith.science/paper/XYJ6IA5W

@misc{pith2026250607017,
  author       = {Pith},
  title        = {Pith review of: Comparative Testing of Subgrid Models for Fast Neutrino Flavor Conversions in Core-collapse Supernova Simulations},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/XYJ6IA5W}},
  note         = {Machine review of arXiv:2506.07017}
}
abstract

We investigate key methodologies of Bhatnagar-Gross-Krook subgrid modeling for neutrino fast flavor conversions (FFC) in core-collapse supernova based on spherically symmetric Boltzmann radiation hydrodynamics simulations. We first examine time integration methods (explicit, implicit, or semi-implicit) and time step control for the subgrid term, and then compare various approaches in the literature approximating FFCs in two aspects: (1) angular dependent survival probability of neutrinos versus simple equipartition condition with a certain baryon mass density threshold, and (2) 4-species treatment versus 3-species assumption ($\nu_x=\bar\nu_x$). We find that the equipartition condition is reasonable for out-going neutrinos, but large deviations emerge in the incoming neutrinos, that has an influence on matter profiles. We also find that the 3-species model, in which flavor conversions evolve towards erasing electron neutrino lepton number (ELN) crossings, behave differently from the 4-species models where heavy leptonic neutrino number (XLN) are appropriately treated in FFC subgrid modeling. In 4-species models, we commonly observe noticeable differences between $\nu_x$ and $\bar\nu_x$, highlighting the limitation in 3-species treatments to study impacts of flavor conversion on neutrino signals. Our result also suggests that FFC models yield lower neutrino heating rate and smaller shock radii compared to cases with no FFC, in agreement with earlier studies employing quantum kinetic neutrino transport. This work provides valuable information towards robust implementation of FFC subgrid model into classical transport, and serves as a pilot study for future multi-dimensional simulations.

Figures

Figures reproduced from arXiv: 2506.07017 by the authors.

Figure 1
Figure 1. FIG. 1. Time-radius map of the FFI growth rates for the 1D [PITH_FULL_IMAGE:figures/full_fig_p005_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. Radial profiles of the density, temperature, [PITH_FULL_IMAGE:figures/full_fig_p006_2.png] view at source ↗
Figure 3
Figure 3. FIG. 3. Time evolution of [PITH_FULL_IMAGE:figures/full_fig_p007_3.png] view at source ↗
Figures from the paper (11 more)
Figure 4
Figure 4. Figure 4: FIG. 4. Top panel: a closer look of the top panel of Fig. [PITH_FULL_IMAGE:figures/full_fig_p008_4.png]
Figure 5
Figure 5. Figure 5: FIG. 5. Time evolution of FFI growth rate (top) and ∆ [PITH_FULL_IMAGE:figures/full_fig_p008_5.png]
Figure 7
Figure 7. Figure 7: It is clear that νx has harder energy spectrum compared to νe and ¯νe. All mixing models show the same trend; νe and ¯νe with energy ϵ ∼ 10 MeV is re￾duced and those with energy ϵ ≳ 30 MeV is enhanced. The enhancement/reduction trend is opposite for νx (¯νx) because th…
Figure 6
Figure 6. Figure 6: FIG. 6. Difference of energy spectrum (total neutrino energy per energy bin) with respect to the no-oscillation model at 2 ms [PITH_FULL_IMAGE:figures/full_fig_p009_6.png]
Figure 7
Figure 7. Figure 7: FIG. 7. Energy spectrum of the no-oscillation model at 2 ms [PITH_FULL_IMAGE:figures/full_fig_p010_7.png]
Figure 8
Figure 8. Figure 8: FIG. 8. Time-radius map of the growth rates for the fiducial (left) and lower- [PITH_FULL_IMAGE:figures/full_fig_p011_8.png]
Figure 9
Figure 9. Figure 9: FIG. 9. Time evolution of the shock radius (top) and neutrino heating rate (bottom) for the fiducial model (left) and lower- [PITH_FULL_IMAGE:figures/full_fig_p012_9.png]
Figure 10
Figure 10. Figure 10: FIG. 10. Radial profiles of neutrino heating rate per unit mass (top), temperature (middle), [PITH_FULL_IMAGE:figures/full_fig_p013_10.png]
Figure 11
Figure 11. Figure 11: FIG. 11. Time evolution of emitted neutrino luminosities [PITH_FULL_IMAGE:figures/full_fig_p014_11.png]
Figure 12
Figure 12. Figure 12: FIG. 12. Same as Fig. 11 but for the lower- [PITH_FULL_IMAGE:figures/full_fig_p015_12.png]
Figure 13
Figure 13. Figure 13: FIG. 13. Radial profile of growth rates of FFI and CFI, 2 ms [PITH_FULL_IMAGE:figures/full_fig_p016_13.png]

Discussion (0). Sign in to comment.

Reference graph

Works this paper leans on

111 extracted references · 10 canonical work pages

  1. [1]

    This model assumes that FFC occurs in a way to smear out ELN-XLN crossings [22]

    BGK subgrid model with 4-species We treat νe, ¯νe, νx and ¯νx distinctively, where νx = νµ = ντ , ¯νx = ¯νµ = ¯ντ [87]. This model assumes that FFC occurs in a way to smear out ELN-XLN crossings [22]. The asymptotic states of the distribution functions f as are written as f as e = ηfe + (1 − η)fx, (17) ¯f as e = η ¯fe + (1 − η) ¯fx, (18) f as x = 1 − η 2 ...

  2. [2]

    The asymptotic distribution is deter- mined by just imposing fνx = f¯νx in Eqs

    BGK subgrid model with 3-species In order to quantify the effect of the 3-species assump- tion, we also perform BGK subgrid model calculation by assuming νx = ¯νx. The asymptotic distribution is deter- mined by just imposing fνx = f¯νx in Eqs. 17-20, which yields f as e = ηfe + (1 − η)fx, (28) ¯f as e = η ¯fe + (1 − η)fx, (29) f as x = 1 − η 4 fe + 1 − η ...

  3. [3]

    We test the effects of such simplified approach on neutrino distribution and CCSN dynamics

    Simple Flavor Equipartition with Density threshold As mentioned earlier, simulations based on the approx- imate transport methods do not have sufficient informa- tion to detect FFI, and resort to a simple equipartition approach for region below a certain density threshold [62– 64, 67]. We test the effects of such simplified approach on neutrino distributi...

  4. [4]

    Mezzacappa, E

    A. Mezzacappa, E. Endeve, O. E. B. Messer, and S. W. Bruenn, Physical, numerical, and computational chal- lenges of modeling neutrino transport in core-collapse supernovae, Living Reviews in Computational Astro- physics 6, 4 (2020), arXiv:2010.09013 [astro-ph.HE]

    arXiv 2020

  5. [5]

    The numerical details of 2D simulation is based on [78], but with general relativistic gravity, and the detailed analysis of dynamics will be reported elsewhere

    2D model We employ CCSN model of the progenitor with zero- age-main-sequence mass with 11 .2 M⊙, taken from [89]. The numerical details of 2D simulation is based on [78], but with general relativistic gravity, and the detailed analysis of dynamics will be reported elsewhere. The 2D model employs exactly the same neutrino-matter interac- tions and EOS, as ...

  6. [6]

    1 shows the time evolution of FFI growth rates (2π/τas) of 1D CCSN simulation without FFC

    1D Simulation from the angle-averaged 2D profile Fig. 1 shows the time evolution of FFI growth rates (2π/τas) of 1D CCSN simulation without FFC. The time t = 0 corresponds to the time 1D simulation started from the angle-averaged 2D profile, t = 270 ms after bounce. Initially, the sudden disappearance of turbulence leads to rapid recession of shock wave, ...

  7. [7]

    V, the fiducial model does not show appreciable difference to the hydrodynamical profile between models with and without FFC

    Lower- Ye model As we shall show in Sec. V, the fiducial model does not show appreciable difference to the hydrodynamical profile between models with and without FFC. There- fore, we additionally perform simulations with Ye artifi- cially lowered by 10%. Although this manipulation itself is artificial, this has clear physical motivation. Multi- dimensiona...

  8. [8]

    Explicit method The simplest method is to estimate the FFC term in an explicit way; f n+1 = f ∗ − ∆t τas (f ∗ − f as), (39) f as is estimated from f ∗, based on Eqs. 17-20. Hereafter, we refer to this time advancement method as the explicit method

Show all 111 references
  1. [9]

    It showed reasonable agreement with the results with direct calculation of QKE

    Semi-implicit method Second method is the time advancement method pro- posed in [69]. It showed reasonable agreement with the results with direct calculation of QKE. By estimating f in the FFC term with f n+1, discretized time evolution equation becomes f n+1 − f ∗ ∆t = − f n+...

  2. [10]

    By re-writing Eqs

    Implicit method If the asymptotic states are given as the linear function of distribution function, it is also possible to estimate the asymptotic states using f n+1. By re-writing Eqs. 17-20, the time evolution equation becomes 1 ∆t f n+1 e − f ∗ e f n+1 x − f ∗ x = − 1 − η τ...

  3. [11]

    The colors denote ∆ t, in the same way as Fig

    Bottom panel: growth rates of FFC for the corresponding time range. The colors denote ∆ t, in the same way as Fig. 3. Cases for implicit methods are only shown. As a reference, horizontal lines representing 2 π × 0.01/∆t are shown in the bottom panel. signed to erase FFI; 3spρ...

  4. [12]

    Janka, T

    H.-T. Janka, T. Melson, and A. Summa, Physics of Core-Collapse Supernovae in Three Dimensions: A Sneak Preview, Annual Review of Nuclear and Particle Science 66, 341 (2016), arXiv:1602.05576 [astro-ph.SR]

    2016 arXiv

  5. [13]

    Janka, Neutrino-Driven Explosions, in Handbook of Supernovae , edited by A

    H.-T. Janka, Neutrino-Driven Explosions, in Handbook of Supernovae , edited by A. W. Alsabti and P. Murdin (Springer, 2017) p. 1095

    2017

  6. [14]

    Janka, Neutrino Emission from Supernovae, in Handbook of Supernovae , edited by A

    H.-T. Janka, Neutrino Emission from Supernovae, in Handbook of Supernovae , edited by A. W. Alsabti and P. Murdin (Springer, 2017) p. 1575

    2017

  7. [15]

    Johns, S

    L. Johns, S. Richers, and M.-R. Wu, Neutrino Os- cillations in Core-Collapse Supernovae and Neutron Star Mergers, arXiv e-prints , arXiv:2503.05959 (2025), arXiv:2503.05959 [astro-ph.HE]

    2025 arXiv

  8. [16]

    Burrows and D

    A. Burrows and D. Vartanyan, Core-collapse super- nova explosion theory, Nature (London) 589, 29 (2021), arXiv:2009.14157 [astro-ph.SR]

    2021 arXiv

  9. [17]

    Mezzacappa, Toward Realistic Models of Core Col- lapse Supernovae: A Brief Review, in The Predic- tive Power of Computational Astrophysics as a Dis- cover Tool , IAU Symposium, Vol

    A. Mezzacappa, Toward Realistic Models of Core Col- lapse Supernovae: A Brief Review, in The Predic- tive Power of Computational Astrophysics as a Dis- cover Tool , IAU Symposium, Vol. 362, edited by D. Bisikalo, D. Wiebe, and C. Boily (2023) pp. 215–227, arXiv:2205.13438 [ast...

    2023 arXiv

  10. [18]

    Boccioli and L

    L. Boccioli and L. Roberti, The Physics of Core- Collapse Supernovae: Explosion Mechanism and Ex- plosive Nucleosynthesis, Universe 10, 148 (2024), arXiv:2403.12942 [astro-ph.SR]

    2024 arXiv

  11. [19]

    Yamada, H

    S. Yamada, H. Nagakura, R. Akaho, A. Harada, S. Fu- rusawa, W. Iwakami, H. Okawa, H. Matsufuru, and K. Sumiyoshi, Physical mechanism of core-collapse su- pernovae that neutrinos drive, Proceedings of the Japan Academy, Series B 100, 190 (2024)

    2024

  12. [20]

    Suzuki, Neutrinos from Core-Collapse Supernova Explosions, Progress of Theoretical and Experimental Physics 2024, 05B101 (2024)

    H. Suzuki, Neutrinos from Core-Collapse Supernova Explosions, Progress of Theoretical and Experimental Physics 2024, 05B101 (2024)

    2024

  13. [21]

    H. T. Janka, Long-Term Multidimensional Models of Core-Collapse Supernovae: Progress and Chal- lenges, arXiv e-prints , arXiv:2502.14836 (2025), arXiv:2502.14836 [astro-ph.HE]

    2025

  14. [22]

    Janka and D

    H.-T. Janka and D. Kresse, Interplay between neutrino kicks and hydrodynamic kicks of neutron stars and black holes, Astrophysics and Space Science 369, 80 (2024), arXiv:2401.13817 [astro-ph.HE]

    2024 arXiv

  15. [23]

    H. Duan, G. M. Fuller, and Y.-Z. Qian, Collective Neu- trino Oscillations, Annual Review of Nuclear and Par- ticle Science 60, 569 (2010), arXiv:1001.2799 [hep-ph]

    2010 arXiv

  16. [24]

    Richers and M

    S. Richers and M. Sen, Fast Flavor Transfor- mations, arXiv e-prints , arXiv:2207.03561 (2022), arXiv:2207.03561 [astro-ph.HE]

    2022 arXiv

  17. [25]

    M. C. Volpe, Neutrinos from dense environments: Fla- vor mechanisms, theoretical approaches, observations, and new directions, Reviews of Modern Physics 96, 025004 (2024), arXiv:2301.11814 [hep-ph]

    2024 arXiv

  18. [26]

    Delfan Azari, S

    M. Delfan Azari, S. Yamada, T. Morinaga, H. Na- gakura, S. Furusawa, A. Harada, H. Okawa, W. Iwakami, and K. Sumiyoshi, Fast collective neu- trino oscillations inside the neutrino sphere in core- collapse supernovae, Phys. Rev. D 101, 023018 (2020), arXiv:1910.06176 [astro-ph.HE]

    2020 arXiv

  19. [27]

    R. F. Sawyer, Speed-up of neutrino transformations in a supernova environment, Phys. Rev. D 72, 045003 (2005), arXiv:hep-ph/0503013 [astro-ph]

    2005 arXiv

  20. [28]

    H. Duan, G. M. Fuller, J. Carlson, and Y.-Z. Qian, Simulation of coherent nonlinear neutrino flavor trans- formation in the supernova environment: Correlated neutrino trajectories, Phys. Rev. D 74, 105014 (2006), arXiv:astro-ph/0606616 [astro-ph]

    2006 arXiv

  21. [29]

    H. Duan, G. M. Fuller, and Y.-Z. Qian, Collective neu- trino flavor transformation in supernovae, Phys. Rev. D 74, 123004 (2006), arXiv:astro-ph/0511275 [astro-ph]

    2006 arXiv

  22. [30]

    R. F. Sawyer, Multiangle instability in dense neu- trino systems, Phys. Rev. D 79, 105003 (2009), arXiv:0803.4319 [astro-ph]

    2009 arXiv

  23. [31]

    Morinaga, Fast neutrino flavor instability and neu- trino flavor lepton number crossings, Phys

    T. Morinaga, Fast neutrino flavor instability and neu- trino flavor lepton number crossings, Phys. Rev. D 105, L101301 (2022), arXiv:2103.15267 [hep-ph]

    2022 arXiv

  24. [32]

    Dasgupta, Collective Neutrino Flavor Instability Re- quires a Crossing, Phys

    B. Dasgupta, Collective Neutrino Flavor Instability Re- quires a Crossing, Phys. Rev. Lett. 128, 081102 (2022), arXiv:2110.00192 [hep-ph]

    2022 arXiv

  25. [33]

    Zaizen and H

    M. Zaizen and H. Nagakura, Simple method for de- termining asymptotic states of fast neutrino-flavor conversion, Phys. Rev. D 107, 103022 (2023), arXiv:2211.09343 [astro-ph.HE]

    2023 arXiv

  26. [34]

    Nagakura, T

    H. Nagakura, T. Morinaga, C. Kato, and S. Yamada, Fast-pairwise Collective Neutrino Oscillations Associ- ated with Asymmetric Neutrino Emissions in Core- collapse Supernovae, Astrophys. J. 886, 139 (2019), arXiv:1910.04288 [astro-ph.HE]

    2019 arXiv

  27. [35]

    Delfan Azari, S

    M. Delfan Azari, S. Yamada, T. Morinaga, W. Iwakami, H. Okawa, H. Nagakura, and K. Sumiyoshi, Linear anal- ysis of fast-pairwise collective neutrino oscillations in core-collapse supernovae based on the results of Boltz- mann simulations, Phys. Rev. D 99, 103011 (2019), arXiv:...

    2019 arXiv

  28. [36]

    Abbar, H

    S. Abbar, H. Duan, K. Sumiyoshi, T. Takiwaki, and M. C. Volpe, Fast neutrino flavor conversion modes in multidimensional core-collapse supernova models: The role of the asymmetric neutrino distributions, Phys. Rev. D 101, 043016 (2020), arXiv:1911.01983 [astro- ph.HE]

    2020 arXiv

  29. [37]

    Morinaga, Spatiotemporal linear instability anal- ysis of collective neutrino flavor conversion in four- dimensional spacetime, Phys

    T. Morinaga, Spatiotemporal linear instability anal- ysis of collective neutrino flavor conversion in four- dimensional spacetime, Phys. Rev. D 103, 083014 (2021), arXiv:2103.14308 [hep-ph]

    2021 arXiv

  30. [38]

    R. Glas, H. T. Janka, F. Capozzi, M. Sen, B. Dasgupta, A. Mirizzi, and G. Sigl, Fast neutrino flavor instability in the neutron-star convection layer of three-dimensional supernova models, Phys. Rev. D 101, 063001 (2020), arXiv:1912.00274 [astro-ph.HE]

    2020

  31. [39]

    Nagakura, A

    H. Nagakura, A. Burrows, L. Johns, and G. M. Fuller, Where, when, and why: Occurrence of fast-pairwise collective neutrino oscillation in three-dimensional core- collapse supernova models, Phys. Rev. D 104, 083025 (2021), arXiv:2108.07281 [astro-ph.HE]

    2021 arXiv

  32. [40]

    Harada and H

    A. Harada and H. Nagakura, Prospects of Fast Flavor Neutrino Conversion in Rotating Core-collapse Super- novae, Astrophys. J. 924, 109 (2022), arXiv:2110.08291 [astro-ph.HE]

    2022 arXiv

  33. [41]

    Akaho, A

    R. Akaho, A. Harada, H. Nagakura, W. Iwakami, H. Okawa, S. Furusawa, H. Matsufuru, K. Sumiyoshi, and S. Yamada, Protoneutron Star Convection Simu- lated with a New General Relativistic Boltzmann Neu- trino Radiation Hydrodynamics Code, Astrophys. J. 944, 60 (2023), arXiv:2206....

    2023 arXiv

  34. [42]

    Akaho, J

    R. Akaho, J. Liu, H. Nagakura, M. Zaizen, and S. Ya- mada, Collisional and fast neutrino flavor instabilities in two-dimensional core-collapse supernova simulation with Boltzmann neutrino transport, Phys. Rev. D 109, 023012 (2024), arXiv:2311.11272 [astro-ph.HE]. 17

    2024 arXiv

  35. [43]

    Xiong, M.-R

    Z. Xiong, M.-R. Wu, N. Khosravi Largani, T. Fis- cher, and G. Mart ´ ınez-Pinedo, Occurrence of fast neu- trino flavor conversions in QCD phase-transition su- pernovae, arXiv e-prints , arXiv:2505.19592 (2025), arXiv:2505.19592 [astro-ph.HE]

    2025

  36. [44]

    Morinaga and S

    T. Morinaga and S. Yamada, Linear stability analysis of collective neutrino oscillations without spurious modes, Phys. Rev. D 97, 023024 (2018), arXiv:1803.05913 [hep- ph]

    2018 arXiv

  37. [45]

    Morinaga, H

    T. Morinaga, H. Nagakura, C. Kato, and S. Yamada, Fast neutrino-flavor conversion in the preshock region of core-collapse supernovae, Physical Review Research 2, 012046 (2020), arXiv:1909.13131 [astro-ph.HE]

    2020 arXiv

  38. [46]

    Bhattacharyya and B

    S. Bhattacharyya and B. Dasgupta, Late-time behavior of fast neutrino oscillations, Phys. Rev. D 102, 063018 (2020)

    2020

  39. [47]

    Morinaga and S

    T. Morinaga and S. Yamada, Spatiotemporal linear instability analysis for arbitrary dispersion relations on the Lefschetz thimble in multidimensional space- time, Physical Review Research 2, 013045 (2020), arXiv:1912.11177 [math-ph]

    2020 arXiv

  40. [48]

    Vlasenko, G

    A. Vlasenko, G. M. Fuller, and V. Cirigliano, Neu- trino quantum kinetics, Phys. Rev. D89, 105004 (2014), arXiv:1309.2628 [hep-ph]

    2014 arXiv

  41. [49]

    Bhattacharyya and B

    S. Bhattacharyya and B. Dasgupta, Fast Flavor Depo- larization of Supernova Neutrinos, Phys. Rev. Lett.126, 061302 (2021), arXiv:2009.03337 [hep-ph]

    2021 arXiv

  42. [50]

    Xiong, M.-R

    Z. Xiong, M.-R. Wu, S. Abbar, S. Bhattacharyya, M. George, and C.-Y. Lin, Evaluating approximate asymptotic distributions for fast neutrino flavor conver- sions in a periodic 1D box, Phys. Rev. D 108, 063003 (2023), arXiv:2307.11129 [astro-ph.HE]

    2023 arXiv

  43. [51]

    Zaizen and H

    M. Zaizen and H. Nagakura, Characterizing quasisteady states of fast neutrino-flavor conversion by stability and conservation laws, Phys. Rev. D 107, 123021 (2023), arXiv:2304.05044 [astro-ph.HE]

    2023 arXiv

  44. [52]

    D. F. G. Fiorillo and G. G. Raffelt, Theory of neutrino fast flavor evolution. Part I. Linear response theory and stability conditions., Journal of High Energy Physics 2024, 225 (2024), arXiv:2406.06708 [hep-ph]

    2024 arXiv

  45. [53]

    D. F. G. Fiorillo and G. G. Raffelt, Theory of neu- trino fast flavor evolution. Part II. Solutions at the edge of instability, arXiv e-prints , arXiv:2409.17232 (2024), arXiv:2409.17232 [hep-ph]

    2024 arXiv

  46. [54]

    D. F. G. Fiorillo, M. Goimil-Garc ´ ıa, and G. G. Raf- felt, Fast Flavor Pendulum: Instability Condition, arXiv e-prints , arXiv:2412.09027 (2024), arXiv:2412.09027 [hep-ph]

    2024 arXiv

  47. [55]

    D. F. G. Fiorillo and G. G. Raffelt, Fast Flavor Conver- sions at the Edge of Instability in a Two-Beam Model, Phys. Rev. Lett. 133, 221004 (2024), arXiv:2403.12189 [hep-ph]

    2024 arXiv

  48. [56]

    Sigl and G

    G. Sigl and G. Raffelt, General kinetic description of relativistic mixed neutrinos, Nuclear Physics B406, 423 (1993)

    1993

  49. [57]

    B. H. J. McKellar and M. J. Thomson, Oscillating neu- trinos in the early Universe, Phys. Rev. D 49, 2710 (1994)

    1994

  50. [58]

    Serreau and C

    J. Serreau and C. Volpe, Neutrino-antineutrino corre- lations in dense anisotropic media, Phys. Rev. D 90, 125040 (2014), arXiv:1409.3591 [hep-ph]

    2014 arXiv

  51. [59]

    Nagakura and M

    H. Nagakura and M. Zaizen, Time-Dependent and Qua- sisteady Features of Fast Neutrino-Flavor Conversion, Phys. Rev. Lett. 129, 261101 (2022), arXiv:2206.04097 [astro-ph.HE]

    2022 arXiv

  52. [60]

    Kartavtsev, G

    A. Kartavtsev, G. Raffelt, and H. Vogel, Neutrino prop- agation in media: Flavor, helicity, and pair correlations, Phys. Rev. D 91, 125020 (2015), arXiv:1504.03230 [hep- ph]

    2015 arXiv

  53. [61]

    D. N. Blaschke and V. Cirigliano, Neutrino quantum kinetic equations: The collision term, Phys. Rev. D 94, 033009 (2016), arXiv:1605.09383 [hep-ph]

    2016 arXiv

  54. [62]

    Froustey, C

    J. Froustey, C. Pitrou, and M. C. Volpe, Neutrino de- coupling including flavour oscillations and primordial nucleosynthesis, Journal of Cosmology and Astroparti- cle Physics 2020, 015 (2020), arXiv:2008.01074 [hep- ph]

    2020 arXiv

  55. [63]

    Kainulainen and H

    K. Kainulainen and H. Parkkinen, Quantum transport theory for neutrinos with flavor and particle-antiparticle mixing, Journal of High Energy Physics 2024, 217 (2024), arXiv:2309.00881 [hep-ph]

    2024 arXiv

  56. [64]

    Kainulainen and H

    K. Kainulainen and H. Parkkinen, Coherent collision integrals for neutrino transport equations, Journal of High Energy Physics 2024, 169 (2024)

    2024

  57. [65]

    Sarikas, D

    S. Sarikas, D. de Sousa Seixas, and G. Raffelt, Spu- rious instabilities in multiangle simulations of collec- tive flavor conversion, Phys. Rev. D 86, 125020 (2012), arXiv:1210.4557 [hep-ph]

    2012 arXiv

  58. [66]

    Nagakura, Roles of Fast Neutrino-Flavor Conver- sion on the Neutrino-Heating Mechanism of Core- Collapse Supernova, Phys

    H. Nagakura, Roles of Fast Neutrino-Flavor Conver- sion on the Neutrino-Heating Mechanism of Core- Collapse Supernova, Phys. Rev. Lett. 130, 211401 (2023), arXiv:2301.10785 [astro-ph.HE]

    2023 arXiv

  59. [67]

    Xiong, M.-R

    Z. Xiong, M.-R. Wu, M. George, C.-Y. Lin, N. Khos- ravi Largani, T. Fischer, and G. Mart ´ ınez-Pinedo, Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects, Phys. Rev. D109, 123008 (2024), arXiv:2402.19252 [astro-ph.HE]

    2024 arXiv

  60. [68]

    Shalgar and I

    S. Shalgar and I. Tamborra, Do we have enough evidence to invalidate the mean-field approximation adopted to model collective neutrino oscillations?, Phys. Rev. D 107, 123004 (2023), arXiv:2304.13050 [astro- ph.HE]

    2023 arXiv

  61. [69]

    Shalgar and I

    S. Shalgar and I. Tamborra, Neutrino flavor conver- sion, advection, and collisions: Toward the full solution, Phys. Rev. D 107, 063025 (2023), arXiv:2207.04058 [astro-ph.HE]

    2023 arXiv

  62. [70]

    Xiong, M.-R

    Z. Xiong, M.-R. Wu, M. George, and C.-Y. Lin, Robust Integration of Fast Flavor Conversions in Classical Neu- trino Transport, Phys. Rev. Lett. 134, 051003 (2025), arXiv:2403.17269 [astro-ph.HE]

    2025 arXiv

  63. [71]

    Nagakura and M

    H. Nagakura and M. Zaizen, Basic characteristics of neutrino flavor conversions in the postshock regions of core-collapse supernova, Phys. Rev. D 108, 123003 (2023), arXiv:2308.14800 [astro-ph.HE]

    2023 arXiv

  64. [72]

    Nagakura, Global features of fast neutrino-flavor con- version in binary neutron star mergers, Phys

    H. Nagakura, Global features of fast neutrino-flavor con- version in binary neutron star mergers, Phys. Rev. D 108, 103014 (2023), arXiv:2306.10108 [astro-ph.HE]

    2023 arXiv

  65. [73]

    Ehring, S

    J. Ehring, S. Abbar, H.-T. Janka, G. Raffelt, and I. Tamborra, Fast neutrino flavor conversion in core- collapse supernovae: A parametric study in 1D mod- els, Phys. Rev. D 107, 103034 (2023), arXiv:2301.11938 [astro-ph.HE]

    2023 arXiv

  66. [74]

    Ehring, S

    J. Ehring, S. Abbar, H.-T. Janka, G. Raffelt, and I. Tamborra, Fast Neutrino Flavor Conversions Can Help and Hinder Neutrino-Driven Explosions, Phys. Rev. Lett. 131, 061401 (2023), arXiv:2305.11207 [astro- ph.HE]

    2023 arXiv

  67. [75]

    K. Mori, T. Takiwaki, K. Kotake, and S. Horiuchi, 18 Three-dimensional core-collapse supernova models with phenomenological treatment of neutrino flavor conver- sions, Publications of the Astronomical Society of Japan 10.1093/pasj/psaf007 (2025), arXiv:2501.15256 [astro- ph.HE]

    2025 arXiv

  68. [76]

    Wang and A

    T. Wang and A. Burrows, The Effect of the Fast-Flavor Instability on Core-Collapse Supernova Models, arXiv e-prints , arXiv:2503.04896 (2025), arXiv:2503.04896 [astro-ph.HE]

    2025 arXiv

  69. [77]

    O. Just, S. Abbar, M.-R. Wu, I. Tamborra, H.-T. Janka, and F. Capozzi, Fast neutrino conversion in hydrody- namic simulations of neutrino-cooled accretion disks, Phys. Rev. D 105, 083024 (2022), arXiv:2203.16559 [astro-ph.HE]

    2022 arXiv

  70. [78]

    Y. Qiu, D. Radice, S. Richers, and M. Bhat- tacharyya, Neutrino Flavor Transformation in Neutron Star Mergers, arXiv e-prints , arXiv:2503.11758 (2025), arXiv:2503.11758 [astro-ph.HE]

    2025 arXiv

  71. [79]

    Iwakami, A

    W. Iwakami, A. Harada, H. Nagakura, R. Akaho, H. Okawa, S. Furusawa, H. Matsufuru, K. Sumiyoshi, and S. Yamada, Principal-axis Analysis of the Edding- ton Tensor for the Early Post-bounce Phase of Rota- tional Core-collapse Supernovae, Astrophys. J. 933, 91 (2022), arXiv:2109....

    2022 arXiv

  72. [80]

    Under 1D, the de- pendences on θ, ϕ (zenith and azimuth angles in con- figuration space) and ϕν (azimuth angle in momentum space) are dropped

    limited to spherical symmetry can be written as 1 α ∂f ∂t + cosθν αr2√γrr ∂ ∂r αr2f − 1 ϵ2 ∂ ∂ϵ ϵ3f ω(t) + 1 sinθν ∂ ∂θν sinθνf ω(θν ) = Srad + Sosc, (1) where t, r, ϵ, θν, α, and γij denote the time, radius, energy, zenith angle in momentum space, lapse function and the spati...

  73. [81]

    Nagakura, L

    H. Nagakura, L. Johns, and M. Zaizen, Bhatnagar- Gross-Krook subgrid model for neutrino quantum kinet- ics, Phys. Rev. D 109, 083013 (2024), arXiv:2312.16285 [astro-ph.HE]

    2024 arXiv

  74. [82]

    Abbar, Applications of machine learning to detecting fast neutrino flavor instabilities in core-collapse super- nova and neutron star merger models, Phys

    S. Abbar, Applications of machine learning to detecting fast neutrino flavor instabilities in core-collapse super- nova and neutron star merger models, Phys. Rev. D 107, 103006 (2023), arXiv:2303.05560 [astro-ph.HE]

    2023 arXiv

  75. [83]

    Abbar and H

    S. Abbar and H. Nagakura, Detecting fast neutrino fla- vor conversions with machine learning, Phys. Rev. D 109, 023033 (2024), arXiv:2310.03807 [astro-ph.HE]

    2024 arXiv

  76. [84]

    Abbar, M.-R

    S. Abbar, M.-R. Wu, and Z. Xiong, Application of neural networks for the reconstruction of supernova neutrino energy spectra following fast neutrino fla- vor conversions, Phys. Rev. D 109, 083019 (2024), arXiv:2401.17424 [astro-ph.HE]

    2024 arXiv

  77. [85]

    Abbar, M.-R

    S. Abbar, M.-R. Wu, and Z. Xiong, Physics-informed neural networks for predicting the asymptotic outcome of fast neutrino flavor conversions, Phys. Rev. D 109, 043024 (2024), arXiv:2311.15656 [astro-ph.HE]

    2024 arXiv

  78. [86]

    P. L. Bhatnagar, E. P. Gross, and M. Krook, A Model for Collision Processes in Gases. I. Small Amplitude Processes in Charged and Neutral One-Component Sys- tems, Physical Review 94, 511 (1954)

    1954

  79. [87]

    Nagakura, K

    H. Nagakura, K. Sumiyoshi, and S. Yamada, Three- dimensional Boltzmann Hydro Code for Core Collapse in Massive Stars. I. Special Relativistic Treatments, The Astrophysical Journal Supplement Supplement Series 214, 16 (2014), arXiv:1407.5632 [astro-ph.HE]

    2014 arXiv

  80. [88]

    Nagakura, W

    H. Nagakura, W. Iwakami, S. Furusawa, K. Sumiyoshi, S. Yamada, H. Matsufuru, and A. Imakura, Three- dimensional Boltzmann-Hydro Code for Core-collapse in Massive Stars. II. The Implementation of Moving- mesh for Neutron Star Kicks, The Astrophysical Jour- nal Supplement Supple...

    2017 arXiv

  81. [89]

    Nagakura, S

    H. Nagakura, S. Furusawa, H. Togashi, S. Rich- ers, K. Sumiyoshi, and S. Yamada, Comparing Treat- ments of Weak Reactions with Nuclei in Simulations of Core-collapse Supernovae, The Astrophysical Jour- nal Supplement Supplement Series 240, 38 (2019), arXiv:1812.09811 [astro-ph.HE]

    2019 arXiv

  82. [90]

    Akaho, A

    R. Akaho, A. Harada, H. Nagakura, K. Sumiyoshi, W. Iwakami, H. Okawa, S. Furusawa, H. Matsufuru, and S. Yamada, Multidimensional Boltzmann Neutrino Transport Code in Full General Relativity for Core- collapse Simulations, Astrophys. J. 909, 210 (2021), arXiv:2010.10780 [astro-ph.HE]

    2021 arXiv

  83. [91]

    Shibata, H

    M. Shibata, H. Nagakura, Y. Sekiguchi, and S. Yamada, Conservative form of Boltzmann’s equation in general relativity, Phys. Rev. D 89, 084073 (2014)

    2014

  84. [92]

    Shibata, Numerical Relativity (World Scientific, 2016)

    M. Shibata, Numerical Relativity (World Scientific, 2016)

    2016

  85. [93]

    S. W. Bruenn, Stellar core collapse - Numerical model and infall epoch, The Astrophysical Journal Supplement Supplement Series 58, 771 (1985)

    1985

  86. [94]

    Langanke and G

    K. Langanke and G. Mart ´ ınez-Pinedo, Shell-model cal- culations of stellar weak interaction rates: II. Weak rates for nuclei in the mass range /A=45-65 in super- novae environments, Nuclear Physics A673, 481 (2000), arXiv:nucl-th/0001018 [nucl-th]

    2000 arXiv

  87. [95]

    Langanke, G

    K. Langanke, G. Mart ´ ınez-Pinedo, J. M. Sampaio, D. J. Dean, W. R. Hix, O. E. Messer, A. Mezzacappa, M. Liebend¨ orfer, H. T. Janka, and M. Rampp, Elec- tron Capture Rates on Nuclei and Implications for Stel- lar Core Collapse, Phys. Rev. Lett. 90, 241102 (2003), arXiv:astro...

    2003 arXiv

  88. [96]

    Juodagalvis, K

    A. Juodagalvis, K. Langanke, W. R. Hix, G. Mart ´ ınez- Pinedo, and J. M. Sampaio, Improved estimate of elec- tron capture rates on nuclei during stellar core collapse, Nuclear Physics A 848, 454 (2010), arXiv:0909.0179 [nucl-th]

    2010 arXiv

  89. [97]

    Furusawa, H

    S. Furusawa, H. Togashi, H. Nagakura, K. Sumiyoshi, S. Yamada, H. Suzuki, and M. Takano, A new equa- tion of state for core-collapse supernovae based on real- istic nuclear forces and including a full nuclear ensem- ble, Journal of Physics G Nuclear Physics 44, 094001 (2017), ...

    2017 arXiv

  90. [98]

    BGK subgrid model with 6-species treatment was also suggested in [100]

  91. [99]

    This situation makes the abundance of ¯νe to be smaller than νe, and FFI is un- likely to appear in the post-shock region

    In the absence of convection, deleptonization is sup- pressed and Ye is kept higher. This situation makes the abundance of ¯νe to be smaller than νe, and FFI is un- likely to appear in the post-shock region

  92. [100]

    S. E. Woosley, A. Heger, and T. A. Weaver, The evo- lution and explosion of massive stars, Rev. Mod. Phys. 74, 1015 (2002)

    2002

  93. [101]

    Tamborra, F

    I. Tamborra, F. Hanke, H.-T. Janka, B. M¨ uller, G. G. Raffelt, and A. Marek, Self-sustained Asymmetry of Lepton-number Emission: A New Phenomenon during the Supernova Shock-accretion Phase in Three Dimen- sions, Astrophys. J. 792, 96 (2014), arXiv:1402.5418 [astro-ph.SR]

    2014 arXiv

  94. [102]

    Nagakura, K

    H. Nagakura, K. Sumiyoshi, and S. Yamada, Possi- ble Early Linear Acceleration of Proto-neutron Stars via Asymmetric Neutrino Emission in Core-collapse Su- pernovae, The Astrophysical Journal Letters 880, L28 (2019), arXiv:1907.04863 [astro-ph.HE]

    2019 arXiv

  95. [103]

    Johns, Collisional Flavor Instabilities of Super- nova Neutrinos, Phys

    L. Johns, Collisional Flavor Instabilities of Super- nova Neutrinos, Phys. Rev. Lett. 130, 191001 (2023), 19 arXiv:2104.11369 [hep-ph]

    2023 arXiv

  96. [104]

    J. Liu, M. Zaizen, and S. Yamada, Systematic study of the resonancelike structure in the collisional flavor in- stability of neutrinos, Phys. Rev. D 107, 123011 (2023), arXiv:2302.06263 [hep-ph]

    2023 arXiv

  97. [105]

    J. Liu, R. Akaho, A. Ito, H. Nagakura, M. Zaizen, and S. Yamada, Universality of the neutrino collisional fla- vor instability in core-collapse supernovae, Phys. Rev. D 108, 123024 (2023), arXiv:2310.05050 [astro-ph.HE]

    2023 arXiv

  98. [106]

    J. Liu, H. Nagakura, R. Akaho, A. Ito, M. Zaizen, S. Fu- rusawa, and S. Yamada, Muon-induced collisional flavor instability in core-collapse supernova, Phys. Rev. D110, 043039 (2024), arXiv:2407.10604 [hep-ph]

    2024 arXiv

  99. [107]

    C. Kato, H. Nagakura, and L. Johns, Collisional flavor swap with neutrino self-interactions, Phys. Rev. D 109, 103009 (2024), arXiv:2309.02619 [astro-ph.HE]

    2024 arXiv

  100. [108]

    Zaizen, Spectral diversity in collisional neutrino- flavor conversion: Flavor equipartition or swap, Phys

    M. Zaizen, Spectral diversity in collisional neutrino- flavor conversion: Flavor equipartition or swap, Phys. Rev. D 111, 103029 (2025), arXiv:2502.09260 [hep-ph]

    2025 arXiv

  101. [109]

    Froustey, Predicting the outcome of colli- sional neutrino flavor conversion, arXiv e-prints , arXiv:2505.16961 (2025), arXiv:2505.16961 [hep-ph]

    J. Froustey, Predicting the outcome of colli- sional neutrino flavor conversion, arXiv e-prints , arXiv:2505.16961 (2025), arXiv:2505.16961 [hep-ph]

    2025 arXiv

  102. [110]

    T. Wang, H. Nagakura, L. Johns, and A. Bur- rows, The Effect of the Collisional Flavor Instabil- ity on Core-Collapse Supernova Models, arXiv e-prints , arXiv:2507.01100 (2025), arXiv:2507.01100 [astro- ph.HE]

    2025

  103. [111]

    J. Liu, H. Nagakura, M. Zaizen, L. Johns, and S. Ya- mada, Asymptotic states of fast neutrino-flavor con- versions in the three-flavor framework, arXiv e-prints , arXiv:2503.18145 (2025), arXiv:2503.18145 [astro- ph.HE]

    2025 arXiv

Pith tools

Reviewed August 7, 2026 · model on record in the stance chip above.