Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (2024)

Physical Review D

covering particles, fields, gravitation, and cosmology
  • Highlights
  • Recent
  • Accepted
  • Collections
  • Authors
  • Referees
  • Search
  • Press
  • About
  • Editorial Team

Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects

Zewei Xiong, Meng-Ru Wu, Manu George, Chun-Yu Lin, Noshad Khosravi Largani, Tobias Fischer, and Gabriel Martínez-Pinedo
Phys. Rev. D 109, 123008 – Published 3 June 2024
  • Article
  • References
  • No Citing Articles

PDFHTMLExport Citation

Abstract

Fast flavor conversions (FFCs) of neutrinos, which can occur in core-collapse supernovae (CCSNe), are multiangle effects. They depend on the angular distribution of the neutrino’s electron lepton number (ELN). In this work, we present a comprehensive study of the FFCs by solving the multienergy and multiangle quantum kinetic equations with an extended set of collisional weak processes based on a static and spherically symmetric CCSN matter background profile. We investigate the emergence and evolution of FFCs in models featuring different ELN angular distributions, considering scenarios with two and three neutrino flavors. The spectrogram method is utilized to illustrate the small-scale spatial structure, and we show that this structure of neutrino flavor coherence and number densities in the nonlinear regime is qualitatively consistent with the dispersion relation analysis. On the coarse-grained level, we find that different asymptotic states can be achieved following the FFCs depending on the locations and shapes of the ELN distributions, despite sharing a common feature of the elimination of the ELN angular crossing. While equilibration among different neutrino flavors may be achieved immediately after the prompt FFCs, it is not a general outcome of the asymptotic state, as subsequent feedback effects from collisional neutrino-matter interactions come into play, particularly for cases where FFCs occur inside the neutrinosphere. The impacts of FFCs and the feedback effect on the net neutrino heating rates, the equilibrium electron fraction of CCSN matter, and the free-streaming neutrino energy spectra are quantitatively assessed. Other aspects including the impact of the vacuum term and the coexistence with other type of flavor instabilities are also discussed.

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (1)
  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (2)
  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (3)
  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (4)
  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (5)
  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (6)
  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (7)

15 More

  • Received 29 February 2024
  • Accepted 2 May 2024

DOI:https://doi.org/10.1103/PhysRevD.109.123008

© 2024 American Physical Society

Physics Subject Headings (PhySH)

  1. Research Areas

Neutrino oscillationsParticle astrophysics

  1. Physical Systems

Neutrinos

Gravitation, Cosmology & Astrophysics

Authors & Affiliations

Zewei Xiong1,*, Meng-Ru Wu2,3,4, Manu George2, Chun-Yu Lin5, Noshad Khosravi Largani6, Tobias Fischer6, and Gabriel Martínez-Pinedo1,7

  • 1GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291 Darmstadt, Germany
  • 2Institute of Physics, Academia Sinica, Taipei 11529, Taiwan
  • 3Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan
  • 4Physics Division, National Center for Theoretical Sciences, Taipei 10617, Taiwan
  • 5National Center for High-performance Computing, Hsinchu 30076, Taiwan
  • 6Institute of Theoretical Physics, University of Wroclaw, plac Maksa Borna 9, 50-204 Wroclaw, Poland
  • 7Institut für Kernphysik (Theoriezentrum), Fachbereich Physik, Technische Universität Darmstadt, Schlossgartenstraße 2, 64289 Darmstadt, Germany
  • *z.xiong@gsi.de

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand

Issue

Vol. 109, Iss. 12 — 15 June 2024

Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (8)
Reuse & Permissions
Access Options
Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (11)

Authorization Required

Other Options
  • Buy Article »
  • Find an Institution with the Article »

×

Images

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (12)

    Figure 1

    Radial profiles of baryonic density, temperature T/10, and Ye (before and after attenuations) for a snapshot at the postbounce time tpb252ms. Orange, blue, and green vertical dashed lines indicate the gain radius, the radii of νe- and ν¯e-spheres at r63, 40, and 35km, respectively.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (13)

    Figure 2

    Radial profiles of ELN distribution in models II–VII that have different attenuated Ye profiles. The angular crossings of ELN are indicated by the location of curves with the white color. Model I (without Ye attenuation) is not shown as it contains no ELN angular crossing.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (14)

    Figure 3

    Deepness ratios of the initial ELN distribution, min(|I|,|I+|)/max(|I|,|I+|), in models II–V (see text for the definition of I±).

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (15)

    Figure 4

    Growth rates Im(Ω) as functions of Kr at r=41.6km in models II (a)–(c)and V (d)–(f). The values of Im(Ω)max for the cases with a1=102 and a1=103 in (a) and (d) are multiplied by 102 and 103, respectively, to show the scalability of the dispersion relation discussed in the text.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (16)

    Figure 5

    Growth rates Im(Ω) (km1) as functions of Kr and r in models II (a)–(c) and V (d)–(f). The cyan dashed curve marks Kr with maximum growth rates.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (17)

    Figure 6

    Maximum growth rates Im(Ω)max as functions of radius r in models II (a) and V (b). For the cases with a1=102 and a1=103, the values of Im(Ω)max are multiplied by 102 and 103, respectively, for easier comparison. Black and orange dotted curves are obtained using the simple analytical formulas in Refs.[11, 135], respectively.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (18)

    Figure 7

    Maximum growth rates Im(Ω)max as functions of radius r for in models II (a) and V (b). The gray shaded areas indicate the radial regions where ELN angular crossings exist in the initial ELN distribution without oscillations. Blue and red curves represent results with parameters in the cases c0v2 and c1v0, respectively. Dotted and solid curves represent the cases using aνν=1 without and with excluding the spurious noncollective modes, respectively. The dashed curve in (b)is with a1=103 and with all the spurious modes excluded.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (19)

    Figure 8

    Evolution of the dimensionless ratio of off-diagonal mixing seμ in 30<r<80km (left) and its associated phase angle ϕeμ within a smaller radial range 50<r<55km (right) for model II.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (20)

    Figure 9

    Spectrograms with respect to Kr and r for different models at different times (a)–(l). The color bar is for the Fourier transformed magnitude log10|Fr,Kr[cm3]|. The cyan dashed curve shows the Kr with maximum growth rates calculated from LSA.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (21)

    Figure 10

    Radial profiles of neutrino number densities between r=38 and 40km at t=64μs in models III and IIIa2.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (22)

    Figure 11

    Radial profiles of neutrino number densities for νe, ν¯e, and νμ in models II–VII (a)–(f).

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (23)

    Figure 12

    Radial profiles of neutrino mean energies for νe, ν¯e, νμ, and ν¯μ in models II–VII (a)–(f).

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (24)

    Figure 13

    Evolution of the angular distributions of the ELN, G(vr) (upper row) and that of each neutrino species at r36km (lower row) in models III (a),(b) and IV (c),(d).

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (25)

    Figure 14

    Evolution of the angular distributions of the ELN, G(vr) (upper row), and that of each neutrino species at r50km (lower row) in models II (a),(b), III (c),(d), and IV (e),(f). Note that ϱνE are shown in 0.2vr1 because most of neutrinos propagate outward.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (26)

    Figure 15

    Radial profiles of neutrino number densities (a) and mean energies (b)in model Vc0.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (27)

    Figure 16

    Comparison of the radial profiles of neutrino number density ratios nν(t)/nν(t=0) between two-flavor (dashed) and three-flavor (solid) schemes for model II at 320μs (a), model IV at 32μs (b), and at 320μs (c). Note that the scales for heavy-lepton neutrinos are labeled on the right axes.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (28)

    Figure 17

    Comparison of the radial profiles of neutrino number density ratios nν(t)/nν(t=0) (blue) in models II (a), III (b), and IV (c)at 64μs with different attenuation factors a1=103 (blue), 2×103 (green), 4×103 (red), and 1×102 (black in model II). Note that the scales for the ratio of νμ are labeled on the right axes.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (29)

    Figure 18

    Comparison of the radial profiles of neutrino number density ratios nν(t)/nν(t=0) between models IV and IVv2 at 64μs. The scale for the ratio of νμ is labeled on the right axis.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (30)

    Figure 19

    Comparison of the specific heating-cooling rate after the prompt FFCs at t=32μs (a) and in the asymptotic state at t=160μs (b)for models II (blue), III (green), IV (cyan), and V (red). The original heating rates without flavor conversions are shown by the black curves and are indistinguishable for all models. The cyan dashed curve in (a)is for model IV at t=3.2μs. The magenta curve in (c)is for model Vc0 at t=32μs, compared to model V (red).

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (31)

    Figure 20

    Comparison of the equilibrium electron fraction Yeν,eq after the prompt FFCs (a) and at a later time t=160μs (b)for models II (blue), III (green), IV (cyan), and V (red). The dashed curves show the corresponding profiles without flavor conversions for comparisons.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (32)

    Figure 21

    Free-streaming neutrino energy spectra at t=320μs in models II (a), III (b), IV (c), V (d), VI (e), IIf3 (g), IIIf3 (h), and IVf3 (i). Note that the (f)shows the spectrum after the prompt FFC at t=64μs in model IV for illustration. The dashed curves show the corresponding spectra without flavor conversions for comparisons.

    Reuse & Permissions

  • Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (33)

    Figure 22

    Radial profiles of neutrino number density (a) and mean energy (b)based on boltztran (black), coseν without NES (green), and coseν with NES (red) in model I.

    Reuse & Permissions

×

Fast neutrino flavor conversions in a supernova: Emergence, evolution, and effects (2024)

References

Top Articles
Latest Posts
Article information

Author: Kieth Sipes

Last Updated:

Views: 6418

Rating: 4.7 / 5 (67 voted)

Reviews: 90% of readers found this page helpful

Author information

Name: Kieth Sipes

Birthday: 2001-04-14

Address: Suite 492 62479 Champlin Loop, South Catrice, MS 57271

Phone: +9663362133320

Job: District Sales Analyst

Hobby: Digital arts, Dance, Ghost hunting, Worldbuilding, Kayaking, Table tennis, 3D printing

Introduction: My name is Kieth Sipes, I am a zany, rich, courageous, powerful, faithful, jolly, excited person who loves writing and wants to share my knowledge and understanding with you.