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The initial geometry of a neutron star's magnetic field, not just its strength, controls how much the field amplifies at merger and how magnetised the ejected matter becomes.

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Initial magnetic field topology, especially anti-aligned poloidal fields, strongly controls post-merger field amplification and ejecta magnetisation in neutron star merger simulations.

T0 review reviewed 2026-08-05 challenge →

load-bearing objection Careful, honest simulation study that makes a plausible case that initial field topology drives post-merger magnetisation and ejecta properties, but the ordering is provisional because key runs lack high-resolution counterparts and the GW dephasing result is error-dominated. the 4 major comments →

arxiv 2508.19342 v1 pith:E5CLUU6A submitted 2025-08-26 astro-ph.HE gr-qc

Magnetic Field Configurations in Binary Neutron Star Mergers II: Inspiral, Merger and Ejecta

William Cook , Eduardo M. Guti\'errez , Sebastiano Bernuzzi , David Radice , Boris Daszuta , Jacob Fields , Peter Hammond , Harshraj Bandyopadhyay
show 1 more author
Maximilian Jacobi
This is my paper
classification astro-ph.HE gr-qc
keywords binary neutron star mergersmagnetic field topologyKelvin-Helmholtz instabilitynumerical relativitymagnetohydrodynamicsgravitational waveskilonova ejectaspontaneous symmetry breaking
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

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 tries to show that the initial magnetic field topology of a binary neutron star is a primary control on what happens after merger: how strongly the field amplifies, how much electromagnetic energy is radiated, and how magnetised the ejected r-process material is. Using a suite of ideal GRMHD merger simulations that differ only in field geometry, it finds that anti-aligned poloidal fields amplify roughly a hundred times more than the aligned baseline during the Kelvin-Helmholtz phase, while toroidal-dominated fields amplify the least; ejecta field strengths then differ by over an order of magnitude. It also finds that the field in the ejecta is largely randomly oriented, supporting random-field thermalisation models for kilonovae, and that bitant-symmetric initial data break symmetry at a universal rate, suggesting a spontaneous symmetry-breaking bifurcation that symmetry-enforced simulations miss. A reader should care because these results connect a poorly constrained input—the interior field structure of neutron stars—to observable outputs: post-merger gravitational-wave dephasing, Poynting flux, and kilonova emission.

Core claim

The paper's central claim is that the topology of the initial magnetic field, not just its strength, controls how strongly the field is amplified during a neutron-star merger and how magnetised the ejected matter becomes. In simulations differing only in field geometry—aligned or anti-aligned poloidal fields, toroidal fields, and mixed poloidal-toroidal fields—the amplification during the Kelvin-Helmholtz instability ranges from a factor of roughly two (aligned toroidal) to roughly one hundred (anti-aligned poloidal), and the average field strength in the ejecta varies by more than an order of magnitude. The paper also reports that the magnetic field in the ejecta is essentially randomly ori

What carries the argument

The central mechanism is the Kelvin-Helmholtz instability at the shearing contact layer formed where the two stars first touch at merger. The instability creates small vortices that wind and stretch magnetic field lines, amplifying field energy; anti-aligned fields increase the current and magnetic tension across the shear layer, enhancing growth, while toroidal fields are weakest in the equatorial region where the shear layer first forms and therefore amplify least. A second, winding-driven phase then grows a toroidal field roughly linearly in time from the remnant's rotation and radial field, with growth suppressed by toroidal initial data and enhanced by asymmetry or by a poloidal-toroida

Load-bearing premise

The ordering of amplification across initial field configurations is physical rather than a numerical artifact: higher-resolution runs amplify about twice as much, but if they or a different reconstruction scheme reversed the hierarchy between anti-aligned, aligned, and toroidal fields, the central claim would collapse.

What would settle it

A resolution or reconstruction study that reverses the amplification ordering—for example high-resolution runs where aligned poloidal fields amplify as much as or more than anti-aligned ones—would falsify the topology-driven amplification claim; so would a local shearing-box simulation of relativistic ideal MHD showing no growth-rate difference when the magnetic field direction flips across the shear layer.

Watch this falsifier. Get emailed when new claim-graph text bears on it.

If this is right

  • Post-merger field amplification and ejecta magnetisation are functions of initial topology, so simulations and population models that vary only field strength undersample the outcome space.
  • Binaries with anti-aligned poloidal fields produce the most magnetised remnants and ejecta at fixed initial field strength, making them the most promising candidates for magnetar-like jets and highly magnetised kilonova ejecta.
  • Toroidal-dominated initial fields suppress both Kelvin-Helmholtz and winding amplification, implying weaker electromagnetic outflows and less magnetised ejecta unless a poloidal component is also present.
  • The random field orientation found in the ejecta supports the 'random' thermalisation model for kilonova light curves, with consequences for predicted luminosity if a coherent radial or toroidal field were instead assumed.
  • Bitant-symmetric simulations miss the spontaneous symmetry breaking of the magnetic field, so full-grid evolution is required to capture polar magnetised ejecta and the associated Poynting flux.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Editorial extension: if the topology dependence is generic, the population fraction of binaries with anti-aligned fields could dominate the rate of bright electromagnetic counterparts, since the same initial field strength yields roughly a hundred times more amplification; the paper does not estimate this population fraction.
  • Editorial extension: the measured power-law exponents in B ∝ ρ^α and β^-1 ∝ ρ^α, which vary with initial topology, could be used as a subgrid prescription for ejecta magnetisation in simulations that cannot resolve the Kelvin-Helmholtz instability; the paper stops at reporting the fits.
  • Editorial extension: because these ideal-MHD runs access reconnection only through numerical dissipation, a local shearing-box study with explicit resistivity would directly test the proposed mechanism that anti-aligned fields enhance amplification through reconnection-facilitated magnetic tension.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 5 minor

Summary. This paper presents GRMHD simulations of binary neutron star mergers with different initial magnetic field topologies (aligned/anti-aligned poloidal, toroidal, mixed, asymmetric), together with variations in EOS, mass ratio, and initial field strength. The authors analyze the post-merger GW signal, the magnetic-field amplification during the Kelvin-Helmholtz and winding phases, the Poynting flux, the development of bitant-symmetry breaking, and the magnetic properties of the ejecta. The main claims are that anti-aligned fields can strongly enhance KHI amplification, toroidal fields suppress it, the initial topology affects the magnetic field strength and magnetization of the ejecta by more than an order of magnitude, the ejecta field is largely randomly oriented, and the growth of asymmetry is consistent with a spontaneous symmetry-breaking bifurcation. The paper is the companion to Paper I (arXiv:2506.18995), which focuses on the remnant and disk.

Significance. If correct, the paper would establish that the initial magnetic field topology, not just its strength, is a primary driver of post-merger magnetization and of the magnetic properties of the ejecta. This is relevant for kilonova modeling, jet-launching timescales, and possible magnetic signatures in post-merger GWs. The study is valuable because it uses a consistent code (GR-Athena++), evolves ideal GRMHD with constrained transport, and includes several complementary diagnostics (energy amplification, max|B|, current, tension, Poynting flux, ejecta 2D histograms). The direct comparison of PPM and WENOZ reconstruction in Appendix A is a notable strength: it quantifies numerical scheme effects rather than ignoring them. The paper is also candid about resolution limitations, noting that HR runs amplify about twice as much as SR runs and that the KHI amplification is not converged in absolute terms.

major comments (4)
  1. [Sec. III B 1 and Fig. 3] The central hierarchy of KHI amplification (POL-UD ~100x, POL-UU ~5x, TOR-PP ~2x) is anchored by SR-only runs for the two extremal configurations POL-UD and TOR-PP/TOR-PM. Only POL-UU and MIX have HR (123 m) counterparts, and those HR runs amplify ~2x more than SR. Since the POL-UD enhancement is attributed to current-sheet/tension effects in an ideal-MHD code where reconnection is numerical and resolution-dependent, the ordering could change at higher resolution. Please provide at least medium- or high-resolution runs for POL-UD and for one toroidal configuration, or explicitly restrict the central claim to 'at fixed resolution'.
  2. [Sec. III A and Appendix A] The GW dephasing claim is not robust to the choice of reconstruction scheme. Appendix A reports that PPM vs WENOZ changes Delta-phi_21 by 12 rad and Delta-phi_33 by 18 rad, i.e. about 70% and 123% of the maximal configuration-to-configuration spread quoted in Sec. III A. Thus the (3,3)-mode dephasing differences between magnetic configurations are smaller than the numerical scheme uncertainty. The paper acknowledges this, but the abstract and conclusion still state that the initial field configuration may 'strongly impact' post-merger dephasing. Please either demonstrate that the same-scheme ordering is stable under a second scheme-controlled comparison, or substantially soften the GW claim.
  3. [Table I and Sec. II C] The reconstruction scheme is confounded with the field topology: POL-UU, MIX, TOR-PP, TOR-PM, and B0 use WENOZ, while BITANT, LOWB, POL-UD, POL-90D, POL-ASYM, STIFF, and POL-Q12 use PPM. Appendix A shows that the scheme changes the merger time by ~0.9 ms, the early ejecta magnetic field by a factor of ~4, and the GW dephasing by tens of radians. Since the topology comparison in Sec. III D and Sec. III A is partly a cross-scheme comparison, the apparent topology dependence could be contaminated. The KHI amplification appears less sensitive in the single POL-UU check, but the ejecta and GW quantities are not. Please add scheme-controlled runs for at least the key topology pairs (e.g., POL-UD and TOR-PP) or otherwise justify why the confound does not affect the conclusions.
  4. [Sec. III D, Fig. 15] The power-law fits B = A1 rho^alpha1 and beta^{-1} = A2 rho^alpha2 are least-squares descriptions of the simulations' own ejecta, not independent predictions, and no fit uncertainties are reported. The fits are contaminated by unphysical pre-merger ejecta before ~5 ms, and alpha drifts with time. Given that Appendix A shows the early ejecta B can differ by a factor of ~4 between reconstruction schemes, the claim that alpha ranges from ~1 (TOR-PP) to ~0.75 (POL-UD) needs error bars and a clearly stated fitting window. Without these, the quantitative statement of 'weaker dependence on density' is not supported beyond a visual trend.
minor comments (5)
  1. [Sec. II C, Eqs. (1)-(3)] The parameters pcut, ns, and the 85/15 poloidal/toroidal split are only referenced to Paper I. Please list their numerical values in this paper for self-containedness.
  2. [Fig. 2] The dephasing scatter plot would benefit from symbols or colors encoding the reconstruction scheme, since Appendix A shows a clear scheme dependence.
  3. [Fig. 3] The lower panel y-axis label 'max |B|' is ambiguous; it should read 'max|B| / max|B(0)|' as in the text.
  4. [Sec. III C] The interpretation of the universal asymmetry growth as a 'spontaneous symmetry breaking bifurcation' is plausible but not proven; numerical noise and the finite set of runs offer alternative explanations. Consider softening 'suggests the presence' to 'is consistent with' and discussing how a convergence study would distinguish these.
  5. [Appendix A] The statement that the PPM configuration has 'marginally more mass ejected' is followed by a 7% difference; it would be useful to state whether this is within the expected numerical error of the mass-flux estimator.

Circularity Check

0 steps flagged

No significant circularity: all central claims are direct comparisons from self-contained simulations; self-citations set initial conditions or code details but are not load-bearing.

full rationale

The paper's central claims are comparisons of outcomes across differing initial magnetic field configurations, all obtained from the same self-contained GR-Athena++ simulations. None of the reported results (KHI amplification ordering, ejecta field strengths, GW dephasing, symmetry breaking) is defined in terms of an input parameter, and no fitted parameter is renamed as a prediction. The B=A rho^alpha fits in Sec. III D 3 and Fig. 15 are explicitly least-squares descriptions of the simulations' own ejecta, used to compare configurations, rather than independent predictions. The anti-aligned-field enhancement is diagnosed post hoc through current and magnetic-tension hierarchies and compared with an external local-simulation result [107]; the ideal-MHD/numerical-reconnection caveat is openly discussed. The GW dephasing result is accompanied by a quantified reconstruction-scheme control in Appendix A, which the paper itself reports can alter the effect by more than the spread across configurations; this is a stated limitation, not circular reasoning. Self-citations appear in the choice of initial data parameters from Paper I and in the 85/15 poloidal/toroidal MIX construction motivated by [50], but these are initial-condition/modeling choices, explicitly described as approximate, and the topology ordering does not reduce to them: the key comparisons (POL-UD vs POL-UU, TOR-PP vs TOR-PM, MIX vs POL-UU) are simulation outputs, not analytic consequences of the initial data definitions. No uniqueness theorem from the authors' prior work is invoked to forbid alternatives, and no ansatz is smuggled in as an external fact. The paper is self-contained against its own simulation ensemble, so no circular step reaches the load-bearing threshold.

Axiom & Free-Parameter Ledger

5 free parameters · 5 axioms · 0 invented entities

The central claims rest on standard NR/GRMHD methods, tabulated microphysics, and chosen initial data; no new physical entity is introduced. The free parameters are simulation setup choices or descriptive fit exponents.

free parameters (5)
  • B0 initial field strength = 5e15 G (5e8 G for LOWB)
    Sets the peak magnetic field in the initial data; chosen by hand, not constrained by observation.
  • Vector potential parameters pcut, ns = set in Paper I
    Shape parameters for Eqs. (1)-(3) controlling the field profile inside the stars; free choices.
  • Atmosphere density and temperature = 1.8e3 g/cm3, 0.1 MeV
    Numerical floor to avoid vacuum in the Euler equations; affects low-density ejecta tails.
  • Poloidal/toroidal mix ratio = 85% poloidal / 15% toroidal
    MIX configuration approximates the saturated state of single-star instabilities from [50]; chosen by hand.
  • Ejecta power-law exponents alpha1, alpha2 = 0.55-1.0 (B-rho), 0.5-2.0 (beta^-1-rho)
    Least-squares fits to the simulations' own ejecta distributions (Fig. 15); descriptive, not predictive.
axioms (5)
  • domain assumption Ideal MHD approximation (infinite conductivity)
    Sec. II A: Maxwell equations evolved in the ideal MHD limit; reconnection is only numerical. Affects the anti-aligned-field amplification mechanism discussion.
  • domain assumption Z4c formulation with moving puncture gauge and 6th-order finite differencing
    Sec. II A: used to evolve the Einstein equations; a standard NR scheme.
  • domain assumption Tabulated EOS SFHo and DD2 from Compose database
    Sec. II A: nuclear equation of state inputs; results may depend on EOS choice.
  • domain assumption Initial data from Lorene (conformally flat, quasi-equilibrium)
    Sec. II B: hydrodynamical initial data; the short 3-orbit inspiral means internal field instabilities are not evolved.
  • domain assumption Atmosphere treatment and primitive recovery via PrimitiveSolver/RePrimAnd
    Sec. II A: low-density floor and inversion scheme; affects low-density ejecta and reconstruction comparisons.

reviewed 2026-08-05 · how reviews work

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Cite this review

Pith. "Pith review of Magnetic Field Configurations in Binary Neutron Star Mergers II: Inspiral, Merger and Ejecta." pith.science (2026). https://pith.science/paper/E5CLUU6A

@misc{pith2026250819342,
  author       = {Pith},
  title        = {Pith review of: Magnetic Field Configurations in Binary Neutron Star Mergers II: Inspiral, Merger and Ejecta},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/E5CLUU6A}},
  note         = {Machine review of arXiv:2508.19342}
}
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abstract

We perform a series of simulations of magnetised Binary Neutron Star mergers, with varying magnetic field topologies in the initial data, as well as varying Equations of State, and mass ratios. In this paper, a companion paper to arXiv:2506.18995, we analyse the impact of the initial field configuration on the gravitational wave signal, the amplification of the magnetic field, and the ejected material. We investigate the dependence of the phase evolution of the gravitational wave in the post-merger on the initial magnetic field, finding that dephasing between the $(\ell=2,m=2)$ mode of the gravitational wave, and the $(2,1)$ and $(3,3)$ modes may be strongly impacted by the numerical reconstruction scheme. The magnetic field amplification during the Kelvin-Helmholtz dominated phase may be considerably enhanced by anti-aligned fields, or suppressed by toroidal fields. The post-merger amplification of the field due to winding may be suppressed by toroidal fields, and enhanced by asymmetries or mixtures of poloidal and toroidal fields. The field strength in the ejecta may be impacted by the initial magnetic field, with configurations which lead to large amplifications and those with mixtures of poloidal and toroidal fields preferentially emitting highly magnetised material in the polar regions, showing a weaker dependence of the magnetic field on the density of the ejecta than in cases that amplify the magnetic field less. We find that the magnetic field is largely randomly oriented in the ejected material, supporting such models used to estimate thermalisation timescales of ejected material. We find that configurations which begin with an initial bitant symmetry break this symmetry uniformly, independent of the initial configuration, when evolved without an enforced symmetry. This behaviour suggests the presence of a spontaneous symmetry breaking bifurcation in the solution.

Figures

Figures reproduced from arXiv: 2508.19342 by Boris Daszuta, David Radice, Eduardo M. Guti\'errez, Harshraj Bandyopadhyay, Jacob Fields, Maximilian Jacobi, Peter Hammond, Sebastiano Bernuzzi, William Cook.

Figure 1
Figure 1. Figure 1: FIG. 1. The real part of the ( [PITH_FULL_IMAGE:figures/full_fig_p006_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2. Upper (Lower) panel: The dephasing between the [PITH_FULL_IMAGE:figures/full_fig_p006_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3. Upper panel: The amplification of the magnetic field [PITH_FULL_IMAGE:figures/full_fig_p009_3.png] view at source ↗
Figure 5
Figure 5. Figure 5: FIG. 5. (Upper panel) The instantaneous luminosity of the [PITH_FULL_IMAGE:figures/full_fig_p009_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: FIG. 6. The ratio between the antisymmetric and symmetric [PITH_FULL_IMAGE:figures/full_fig_p010_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: FIG. 7. 2D slices in [PITH_FULL_IMAGE:figures/full_fig_p013_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: FIG. 8. 2D slices in [PITH_FULL_IMAGE:figures/full_fig_p014_8.png] view at source ↗
Figure 9
Figure 9. Figure 9: FIG. 9. Histograms binned over various quantities demonstrating the cumulative proportion of the total ejected mass up [PITH_FULL_IMAGE:figures/full_fig_p015_9.png] view at source ↗
Figure 10
Figure 10. Figure 10: FIG. 10. Upper left panel: The total ejected mass from the binary merger. Upper central panel: The ejected mass flux. Upper [PITH_FULL_IMAGE:figures/full_fig_p016_10.png] view at source ↗
Figure 11
Figure 11. Figure 11: FIG. 11. 2D histograms demonstrating the make up of the cumulative ejected matter at the end of the [PITH_FULL_IMAGE:figures/full_fig_p018_11.png] view at source ↗
Figure 12
Figure 12. Figure 12: FIG. 12. 2D histograms of magnetic field strength against density for magnetised configurations. The color shading demon [PITH_FULL_IMAGE:figures/full_fig_p019_12.png] view at source ↗
Figure 13
Figure 13. Figure 13: FIG. 13. 2D histograms of [PITH_FULL_IMAGE:figures/full_fig_p019_13.png] view at source ↗
Figure 14
Figure 14. Figure 14: FIG. 14. 2D histograms of [PITH_FULL_IMAGE:figures/full_fig_p020_14.png] view at source ↗
Figure 15
Figure 15. Figure 15: FIG. 15. Upper (Lower) panel: Evolution of scaling expo [PITH_FULL_IMAGE:figures/full_fig_p020_15.png] view at source ↗
Figure 16
Figure 16. Figure 16: FIG. 16. Mass averaged value of [PITH_FULL_IMAGE:figures/full_fig_p021_16.png] view at source ↗
Figure 17
Figure 17. Figure 17: FIG. 17. Upper row: The GW strain amplitude for configura [PITH_FULL_IMAGE:figures/full_fig_p023_17.png] view at source ↗
Figure 18
Figure 18. Figure 18: FIG. 18. The magnetic field amplification for configuration [PITH_FULL_IMAGE:figures/full_fig_p024_18.png] view at source ↗
Figure 20
Figure 20. Figure 20: FIG. 20. The magnetic field strength in the ejected material [PITH_FULL_IMAGE:figures/full_fig_p024_20.png] view at source ↗

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Reference graph

Works this paper leans on

127 extracted references · 9 canonical work pages · cited by 2 Pith papers · 7 internal anchors

  1. [1]

    Overview We first discuss the overall evolution of the ejected material. In Fig. 7 and Fig. 8 we show the evolution of the ejected material at large distances at two time slices, ∼ 6.5ms post-merger, and the final time in the simu- lation. We note that the final time of each run is not the same, we refer the reader to Table 1 in Paper I for the duration o...

  2. [2]

    We first demonstrate the mass weighted compo- sition of the ejecta at the end of our simulations in the histograms in Fig

    Impact of magnetic field configuration on ejecta We now discuss the composition of the ejected mate- rial, and the impact of the magnetic field configuration on it. We first demonstrate the mass weighted compo- sition of the ejecta at the end of our simulations in the histograms in Fig. 9. To complement this discussion with a measure of the time evolution...

  3. [3]

    We calcu- late the luminosity associated to the radial Poynting flux, −10 0 10 20 30 t − tmrg (ms) 0.0 0.2 0.4 0.6 0.8 1.0 bφbφ/b2 Star 1 POL-UU MIX TOR-PP TOR-PM FIG

    Poynting Flux After the merger, energy is radiated through the elec- tromagnetic field through the Poynting flux. We calcu- late the luminosity associated to the radial Poynting flux, −10 0 10 20 30 t − tmrg (ms) 0.0 0.2 0.4 0.6 0.8 1.0 bφbφ/b2 Star 1 POL-UU MIX TOR-PP TOR-PM FIG. 4. The toroidal magnetic energy as a proportion of the total magnetic energ...

  4. [4]

    random” configuration; finding that a toroidal field may “trap

    Magnetic field structure We now discuss the magnetic field orientation in the ejected material, by demonstrating the proportion of the magnetic field strength in the radial and toroidal com- ponents, respectively Br/|B| and Bϕ/|B|. The average of the radial and toroidal components oscillate around zero, with the magnitude of the oscillations, especially f...

  5. [5]

    D. M. Siegel, R. Ciolfi, and L. Rezzolla, Astrophys. J. 785, L6 (2014), arXiv:1401.4544 [astro-ph.HE]

    Pith/arXiv arXiv 2014

  6. [6]

    In the left panel, third row of Fig

    Magnetic field in the ejecta We now consider the impact of the magnetic field con- figuration on the magnetic field itself in the ejecta. In the left panel, third row of Fig. 10 we demonstrate the average magnetic field strength. We note that the hi- erarchy of this strength shares some features with, but does not identically match that of the global magn...

  7. [7]

    D. M. Siegel and B. D. Metzger, Phys. Rev. Lett. 119, 231102 (2017), arXiv:1705.05473 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  8. [8]

    E. M. Guti´ errez, W. Cook, D. Radice, S. Bernuzzi, J. Fields, P. Hammond, B. Daszuta, H. Bandyopadhyay, and M. Jacobi, (2025), arXiv:2506.18995 [astro-ph.HE]

    arXiv 2025

  9. [9]

    F. A. Rasio and S. L. Shapiro, Classical and Quantum Gravity 16, R1 (1999), arXiv:gr-qc/9902019 [gr-qc]

    Pith/arXiv arXiv 1999

  10. [10]

    Here ut is the timelike covariant com- ponent of the fluid 4-velocity, while h = 1 + ϵ + p ρ is the fluid enthalpy

    In this discussion we classify as ejecta, material that is unbound according to the Bernoulli criterion, that is material, as extracted on a sphere of radius 295km, for which hut < −1. Here ut is the timelike covariant com- ponent of the fluid 4-velocity, while h = 1 + ϵ + p ρ is the fluid enthalpy. ϵ is the fluid specific internal energy. In the simulati...

  11. [11]

    Price and S

    D. Price and S. Rosswog, Science 312, 719 (2006), arXiv:astro-ph/0603845 [astro-ph]

    Pith/arXiv arXiv 2006

  12. [12]

    Kiuchi, P

    K. Kiuchi, P. Cerd´ a-Dur´ an, K. Kyutoku, Y. Sekiguchi, and M. Shibata, Phys. Rev. D 92, 124034 (2015), arXiv:1509.09205 [astro-ph.HE]

    Pith/arXiv arXiv 2015

  13. [13]

    Kiuchi, K

    K. Kiuchi, K. Kyutoku, Y. Sekiguchi, M. Shi- bata, and T. Wada, Phys.Rev. D90, 041502 (2014), arXiv:1407.2660 [astro-ph.HE]

    Pith/arXiv arXiv 2014

  14. [14]

    E. R. Most, J. Peterson, L. Scurto, H. Pais, and V. Dex- heimer, (2025), arXiv:2506.21696 [astro-ph.HE]

    Pith/arXiv arXiv 2025

  15. [15]

    M¨ osta, D

    P. M¨ osta, D. Radice, R. Haas, E. Schnetter, and S. Bernuzzi, Astrophys. J. Lett. 901, L37 (2020), arXiv:2003.06043 [astro-ph.HE]

    Pith/arXiv arXiv 2020

  16. [16]

    Curtis, P

    S. Curtis, P. M¨ osta, Z. Wu, D. Radice, L. Roberts, G. Ricigliano, and A. Perego, Mon. Not. Roy. Astron. Soc. 518, 5313 (2022), arXiv:2112.00772 [astro-ph.HE]

    Pith/arXiv arXiv 2022

  17. [17]

    Combi and D

    L. Combi and D. M. Siegel, Astrophys. J. 944, 28 (2023), arXiv:2206.03618 [astro-ph.HE]

    Pith/arXiv arXiv 2023

  18. [18]

    de Haas, P

    S. de Haas, P. Bosch, P. M¨ osta, S. Curtis, and N. Schut, (2022), arXiv:2208.05330 [astro-ph.HE]

    Pith/arXiv arXiv 2022

  19. [19]

    Kiuchi, S

    K. Kiuchi, S. Fujibayashi, K. Hayashi, K. Kyutoku, Y. Sekiguchi, and M. Shibata, Phys. Rev. Lett. 131, 011401 (2023), arXiv:2211.07637 [astro-ph.HE]

    Pith/arXiv arXiv 2023

  20. [20]

    Combi and D

    L. Combi and D. M. Siegel, Phys. Rev. Lett. 131, 231402 (2023), arXiv:2303.12284 [astro-ph.HE]

    Pith/arXiv arXiv 2023

  21. [21]

    D. A. Coulter et al., Science 358, 1556 (2017), arXiv:1710.05452 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  22. [22]

    Pian et al., Nature (2017), 10.1038/nature24298, arXiv:1710.05858 [astro-ph.HE]

    E. Pian et al., Nature (2017), 10.1038/nature24298, arXiv:1710.05858 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  23. [23]

    Kasen, B

    D. Kasen, B. Metzger, J. Barnes, E. Quataert, and E. Ramirez-Ruiz, Nature (2017), 10.1038/nature24453, [Nature551,80(2017)], arXiv:1710.05463 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  24. [24]

    Li and B

    L.-X. Li and B. Paczynski, Astrophys.J. 507, L59 (1998), arXiv:astro-ph/9807272 [astro-ph]

    Pith/arXiv arXiv 1998

  25. [25]

    S. R. Kulkarni, (2005), arXiv:astro-ph/0510256 [astro- ph]

    Pith/arXiv arXiv 2005

  26. [26]

    Metzger, G

    B. Metzger, G. Martinez-Pinedo, S. Darbha, E. Quataert, A. Arcones, et al., Mon.Not.Roy.Astron.Soc. 406, 2650 (2010), arXiv:1001.5029 [astro-ph.HE]

    Pith/arXiv arXiv 2010

  27. [27]

    B. P. Abbott et al. (GROND, SALT Group, Oz- Grav, DFN, INTEGRAL, Virgo, Insight-Hxmt, MAXI Team, Fermi-LAT, J-GEM, RATIR, IceCube, CAAS- TRO, L W A, ePESSTO, GRA WITA, RIMAS, SKA South Africa/MeerKAT, H.E.S.S., 1M2H Team, IKI- GW Follow-up, Fermi GBM, Pi of Sky, DWF (Deeper Wider Faster Program), Dark Energy Survey, MAS- TER, AstroSat Cadmium Zinc Telluri...

    Pith/arXiv arXiv 2017

  28. [28]

    Narayan, B

    R. Narayan, B. Paczynski, and T. Piran, Astrophys. J. 395, L83 (1992), arXiv:astro-ph/9204001

    Pith/arXiv arXiv 1992

  29. [29]

    Soares-Santos et al

    M. Soares-Santos et al. (DES), Astrophys. J. 848, L16 (2017), arXiv:1710.05459 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  30. [30]

    Arcavi et al., Nature 551, 64 (2017), arXiv:1710.05843 [astro-ph.HE]

    I. Arcavi et al., Nature 551, 64 (2017), arXiv:1710.05843 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  31. [31]

    S. I. Blinnikov, I. D. Novikov, T. V. Perevodchikova, and A. G. Polnarev, Soviet Astronomy Letters 10, 177 (1984), arXiv:1808.05287 [astro-ph.HE]

    Pith/arXiv arXiv 1984

  32. [32]

    Paczynski, Astrophys

    B. Paczynski, Astrophys. J. 308, L43 (1986)

    1986

  33. [33]

    Goodman, Astrophys

    J. Goodman, Astrophys. J. Lett. 308, L47 (1986)

    1986

  34. [34]

    Eichler, M

    D. Eichler, M. Livio, T. Piran, and D. N. Schramm, Nature 340, 126 (1989)

    1989

  35. [35]

    C. T. Y. Chung and A. Melatos, mnras 411, 2471 (2011), arXiv:1010.2816 [astro-ph.SR]

    Pith/arXiv arXiv 2011

  36. [36]

    B. P. Abbott et al. (Virgo, LIGO Scientific), Phys. Rev. Lett. 119, 161101 (2017), arXiv:1710.05832 [gr-qc]

    Pith/arXiv arXiv 2017

  37. [37]

    Goldstein et al., Astrophys

    A. Goldstein et al., Astrophys. J. 848, L14 (2017), arXiv:1710.05446 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  38. [38]

    Savchenko et al., Astrophys

    V. Savchenko et al., Astrophys. J. 848, L15 (2017), arXiv:1710.05449 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  39. [39]

    Piran, Rev

    T. Piran, Rev. Mod. Phys. 76, 1143 (2004), arXiv:astro- ph/0405503

    arXiv 2004

  40. [40]

    Kumar and B

    P. Kumar and B. Zhang, Phys. Rept. 561, 1 (2014), arXiv:1410.0679 [astro-ph.HE]

    Pith/arXiv arXiv 2014

  41. [41]

    Short gamma-ray burst central engines

    R. Ciolfi, Int. J. Mod. Phys. D 27, 1842004 (2018), arXiv:1804.03684 [astro-ph.HE]

    work page internal anchor Pith review Pith/arXiv arXiv 2018

  42. [42]

    Kiuchi, M

    K. Kiuchi, M. Shibata, and S. Yoshida, Phys. Rev. D78, 024029 (2008), arXiv:0805.2712 [astro-ph]

    Pith/arXiv arXiv 2008

  43. [43]

    C. T. Y. Chung and A. Melatos, mnras 415, 1703 (2011), arXiv:1104.1016 [astro-ph.SR]

    Pith/arXiv arXiv 2011

  44. [44]

    A. V. Bilous, A. L. Watts, A. K. Harding, T. E. Riley, Z. Arzoumanian, S. Bogdanov, K. C. Gendreau, P. S. Ray, S. Guillot, W. C. G. Ho, and D. Chakrabarty, The Astrophysical Journal Letters 887, L23 (2019)

    2019

  45. [45]

    T. E. Riley et al., Astrophys. J. Lett. 918, L27 (2021), arXiv:2105.06980 [astro-ph.HE]

    Pith/arXiv arXiv 2021

  46. [46]

    Choudhury, T

    D. Choudhury, T. Salmi, S. Vinciguerra, T. E. Riley, Y. Kini, A. L. Watts, B. Dorsman, S. Bogdanov, S. Guil- lot, P. S. Ray, D. J. Reardon, R. A. Remillard, A. V. Bilous, D. Huppenkothen, J. M. Lattimer, N. Ruther- ford, Z. Arzoumanian, K. C. Gendreau, S. M. Morsink, 26 and W. C. G. Ho, Astrophys. J. Lett. 971, L20 (2024), arXiv:2407.06789 [astro-ph.HE]

    Pith/arXiv arXiv 2024

  47. [47]

    Salmi, J

    T. Salmi, J. S. Deneva, P. S. Ray, A. L. Watts, D. Choudhury, Y. Kini, S. Vinciguerra, H. T. Cro- martie, M. T. Wolff, Z. Arzoumanian, S. Bogdanov, K. Gendreau, S. Guillot, W. C. G. Ho, S. M. Morsink, I. Cognard, L. Guillemot, G. Theureau, and M. Kerr, Astrophys. J. 976, 58 (2024), arXiv:2409.14923 [astro- ph.HE]

    Pith/arXiv arXiv 2024

  48. [48]

    J. A. Pons and D. Vigan` o, (2019), 10.1007/s41115-019- 0006-7, arXiv:1911.03095 [astro-ph.HE]

    Pith/arXiv arXiv 2019

  49. [49]

    W. Cook, B. Daszuta, J. Fields, P. Hammond, S. Al- banesi, F. Zappa, S. Bernuzzi, and D. Radice, Astro- phys. J. Suppl. 277, 3 (2025), arXiv:2311.04989 [gr-qc]

    Pith/arXiv arXiv 2025

  50. [50]

    Ciolfi, S

    R. Ciolfi, S. K. Lander, G. M. Manca, and L. Rezzolla, Astrophys.J. 736, L6 (2011), arXiv:1105.3971 [gr-qc]

    Pith/arXiv arXiv 2011

  51. [51]

    Ciolfi and L

    R. Ciolfi and L. Rezzolla, Mon. Not. Roy. Astron. Soc. 435, L43 (2013), arXiv:1306.2803 [astro-ph.SR]

    Pith/arXiv arXiv 2013

  52. [52]

    P. D. Lasky, B. Zink, K. D. Kokkotas, and K. Glampedakis, Astrophys. J. Lett. 735, L20 (2011), arXiv:1105.1895 [astro-ph.SR]

    Pith/arXiv arXiv 2011

  53. [53]

    A. G. Pili, N. Bucciantini, and L. Del Zanna, Mon. Not. Roy. Astron. Soc. 439, 3541 (2014), arXiv:1401.4308 [astro-ph.HE]

    Pith/arXiv arXiv 2014

  54. [54]

    A. G. Pili, N. Bucciantini, and L. Del Zanna, Mon. Not. Roy. Astron. Soc. 470, 2469 (2017), arXiv:1705.03795 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  55. [55]

    A. Sur, W. Cook, D. Radice, B. Haskell, and S. Bernuzzi, Mon. Not. Roy. Astron. Soc. 511, 3983 (2022), arXiv:2108.11858 [astro-ph.HE]

    Pith/arXiv arXiv 2022

  56. [56]

    Flowers and M

    E. Flowers and M. A. Ruderman, Astrophys. J. 215, 302 (1977)

    1977

  57. [57]

    W. Cook, R. K. Joshi, S. Bernuzzi, B. Haskell, and J. Fields, (2025), arXiv:2506.08037 [astro-ph.HE]

    Pith/arXiv arXiv 2025

  58. [58]

    R. J. Tayler, Proceedings of the Physical Society B 70, 31 (1957)

    1957

  59. [59]

    R. J. Tayler, Mon. Not. R. Astron. Soc. 161, 365 (1973)

    1973

  60. [60]

    G. A. E. Wright, Mon. Not. R. Astron. Soc. 162, 339 (1973)

    1973

  61. [61]

    Markey and R

    P. Markey and R. J. Tayler, Mon. Not. R. Astron. Soc. 163, 77 (1973)

    1973

  62. [62]

    Markey and R

    P. Markey and R. J. Tayler, Mon. Not. R. Astron. Soc. 168, 505 (1974)

    1974

  63. [63]

    A. Sur, B. Haskell, and E. Kuhn, Mon. Not. Roy. As- tron. Soc. 495, 1360 (2020), arXiv:2002.10357 [astro- ph.HE]

    Pith/arXiv arXiv 2020

  64. [64]

    Braithwaite and H

    J. Braithwaite and H. C. Spruit, Astron. Astrophys. 450, 1097 (2006), arXiv:astro-ph/0510287

    Pith/arXiv arXiv 2006

  65. [65]

    Binary Neutron Star Mergers and Short Gamma-Ray Bursts: Effects of Magnetic Field Orientation, Equation of State, and Mass Ratio

    T. Kawamura, B. Giacomazzo, W. Kastaun, R. Ciolfi, A. Endrizzi, L. Baiotti, and R. Perna, Phys. Rev. D94, 064012 (2016), arXiv:1607.01791 [astro-ph.HE]

    work page internal anchor Pith review Pith/arXiv arXiv 2016

  66. [66]

    M. Ruiz, A. Tsokaros, and S. L. Shapiro, Phys. Rev. D 101, 064042 (2020), arXiv:2001.09153 [astro-ph.HE]

    Pith/arXiv arXiv 2020

  67. [67]

    Aguilera-Miret, C

    R. Aguilera-Miret, C. Palenzuela, F. Carrasco, S. Ross- wog, and D. Vigan` o, Phys. Rev. D110, 083014 (2024), arXiv:2407.20335 [astro-ph.HE]

    Pith/arXiv arXiv 2024

  68. [68]

    Bamber, A

    J. Bamber, A. Tsokaros, M. Ruiz, and S. L. Shapiro, (2024), arXiv:2411.00943 [gr-qc]

    Pith/arXiv arXiv 2024

  69. [69]

    Tsokaros, J

    A. Tsokaros, J. Bamber, M. Ruiz, and S. L. Shapiro, (2024), arXiv:2411.00939 [gr-qc]

    Pith/arXiv arXiv 2024

  70. [70]

    Effects of Landau quantization on neutrino emission and absorption

    M. Kumamoto and C. Welch, Phys. Rev. D 111, 063009 (2025), arXiv:2412.02925 [nucl-th]

    work page internal anchor Pith review Pith/arXiv arXiv 2025

  71. [71]

    Aguilera-Miret, D

    R. Aguilera-Miret, D. Vigan` o, and C. Palenzuela, As- trophys. J. Lett. 926, L31 (2022), arXiv:2112.08406 [gr- qc]

    Pith/arXiv arXiv 2022

  72. [72]

    Aguilera-Miret, C

    R. Aguilera-Miret, C. Palenzuela, F. Carrasco, and D. Vigan` o, (2023), arXiv:2307.04837 [astro-ph.HE]

    Pith/arXiv arXiv 2023

  73. [73]

    Crustal magnetic fields do not lead to large magnetic-field amplifications in binary neutron-star mergers

    M. Chabanov, S. D. Tootle, E. R. Most, and L. Rezzolla, Astrophys. J. Lett. 945, L14 (2023), arXiv:2211.13661 [astro-ph.HE]

    work page internal anchor Pith review Pith/arXiv arXiv 2023

  74. [74]

    Aguilera-Miret, J.-E

    R. Aguilera-Miret, J.-E. Christian, S. Rosswog, and C. Palenzuela, (2025), arXiv:2504.10604 [astro-ph.HE]

    arXiv 2025

  75. [75]

    Nuclear Reaction Screening, Weak Interactions, and r-Process Nucleosynthesis in High Magnetic Fields

    M. Famiano, A. B. Balantekin, T. Kajino, M. Kusakabe, K. Mori, and Y. Luo, Astrophys. J. 898, 163 (2020), arXiv:2006.14148 [astro-ph.HE]

    work page internal anchor Pith review Pith/arXiv arXiv 2020

  76. [76]

    Tambe, D

    P. Tambe, D. Chatterjee, M. Alford, and A. Haber, (2024), arXiv:2409.09423 [nucl-th]

    Pith/arXiv arXiv 2024

  77. [77]

    M. Ruiz, D. Hilditch, and S. Bernuzzi, Phys. Rev. D83, 024025 (2011), arXiv:1010.0523 [gr-qc]

    work page internal anchor Pith review Pith/arXiv arXiv 2011

  78. [78]

    Barnes, D

    J. Barnes, D. Kasen, M.-R. Wu, and G. Martinez-Pinedo, Astrophys. J. 829, 110 (2016), arXiv:1605.07218 [astro-ph.HE]

    Pith/arXiv arXiv 2016

  79. [79]

    Daszuta, F

    B. Daszuta, F. Zappa, W. Cook, D. Radice, S. Bernuzzi, and V. Morozova, Astrophys. J. Supp. 257, 25 (2021), arXiv:2101.08289 [gr-qc]

    Pith/arXiv arXiv 2021

  80. [80]

    GR-Athena++: Magnetohy- drodynamical Evolution with Dynamical Space-Time,

    B. Daszuta and W. Cook, “GR-Athena++: Magnetohy- drodynamical Evolution with Dynamical Space-Time,” (2025) arXiv:2406.05126 [gr-qc]

    Pith/arXiv arXiv 2025

Showing first 80 references.

This paper was first reviewed by deepseek-v4-flash on August 5, 2026.