Pith. sign in

REVIEW 3 major objections 5 minor 104 references

Rotating neutron stars with a purely toroidal magnetic field still obey quasi-linear relations between their fundamental-mode frequencies and stellar compactness or rotation energy, and the ratio of the two mode frequencies can jointly infe

Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →

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

T0 review · deepseek-v4-flash

2026-08-04 18:06 UTC pith:ZFQVD7D6

load-bearing objection Solid new numerical result on rotating magnetized f-modes, but the frequency-ratio inversion is underdetermined and the 'prediction' language overstates what are in-sample fits. the 3 major comments →

arxiv 2509.10150 v1 pith:ZFQVD7D6 submitted 2025-09-12 astro-ph.HE

Magnetic effects on fundamental modes in rotating neutron stars with a purely toroidal magnetic field

Anson Ka Long Yip , Tjonnie Guang Feng Li This is my paper
classification astro-ph.HE
keywords neutron starsfundamental modestoroidal magnetic fieldrotationgravitational wave asteroseismologyT/|W|mode frequenciesGRMHD simulations
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.

This paper extends established linear frequency relations for rotating neutron stars to include a purely toroidal magnetic field, using axisymmetric general-relativistic magnetohydrodynamic simulations in dynamical spacetime. It claims that the quasi-linear relations connecting the fundamental l=0 radial mode f_F and l=2 quadrupolar mode f_2f to compactness M/R and kinetic-to-binding energy ratio T/|W| remain valid when the field is present, with the slope controlled by the toroidal magnetization constant K_m. It further claims that measuring the frequency ratio f_2f/f_F allows simultaneous inference of T/|W| and maximum field strength B_max, providing a gravitational-wave route to interior magnetic-field and rotation measurements that electromagnetic observations cannot offer. The paper also reports that differential rotation changes the frequencies only mildly, so uniform-rotation fits remain useful.

Core claim

The central discovery is that magnetic suppression of fundamental-mode frequencies does not destroy the quasi-universal linear trends seen in unmagnetized rotating neutron stars; it instead modulates their slopes. Across five sequences with toroidal magnetization constants K_m from 0.5 to 2.5, corresponding to maximum field strengths of order 10^17 G, the mode frequencies grow approximately linearly with both M/R and T/|W|, with residues below about 1-2%. The sign of the slope shift differs for the two modes: the l=0 slope a_1^F decreases with K_m while the l=2 slope a_1^{2f} increases, and similarly the T/|W| slopes move in opposite directions. Consequently, the ratio f_2f/f_F becomes a dia

What carries the argument

The machinery is a set of 2D axisymmetric ideal GRMHD simulations of equilibrium neutron-star models with a purely toroidal magnetic field, evolved in a dynamical spacetime under the conformally flat condition. The toroidal field is set by a magnetic polytropic law B_phi = alpha^{-1} K_m (rho h vartheta^2)^m with m=1; K_m is the toroidal magnetization constant that labels five sequences of models with B_max ~ O(10^17) G. The fundamental l=0 and l=2 modes are excited by velocity perturbations and extracted via Fourier analysis. Linear fits f_pred = a_0 - a_1 M/R and f_pred = b_0 - b_1 T/|W| serve as the working relations, and a radial-basis-function interpolation of the ratio f_2f/f_F over th

Load-bearing premise

The load-bearing premise is that 2D axisymmetry captures the physics of a purely toroidal magnetic field: the simulations suppress the instabilities that such fields are known to have, so if those instabilities grow in real neutron stars, the computed mode frequencies and linear relations would not describe actual signals.

What would settle it

Evolve the same equilibrium models in full three dimensions without axisymmetry and measure f_F and f_2f: if the frequencies or the f_2f/f_F ratio depart from the paper's linear fits and contours, the central claim is falsified. A complementary observational check would be a detected post-merger gravitational-wave signal whose measured f_2f/f_F falls outside the predicted T/|W|-B_max contour region for any plausible stellar parameters.

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

If this is right

  • The quasi-linear relations between f_F, f_2f, M/R, and T/|W| extend to rotating stars with a toroidal magnetic field, so magnetic suppression alone does not break the linear trend.
  • The slope of each relation depends on the toroidal magnetization constant K_m, giving an in-principle handle on interior magnetic field strength from mode-frequency measurements.
  • A measured frequency ratio f_2f/f_F maps to localized regions in the T/|W|-B_max plane, allowing joint inference of rotation and maximum field strength.
  • Differential rotation (under the j-constant law with ~A=1) shifts f_F by at most about 2.5% and f_2f by at most about 5% relative to uniform-rotation predictions, so the uniform-rotation fits remain approximately valid for those models.
  • With third-generation detectors, the mode frequencies (~1.2-1.6 kHz) could be measured accurately enough to determine f_2f/f_F to about 1% or better, translating to comparable precision on inferred T/|W| and B_max.

Where Pith is reading between the lines

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

  • A natural stress test is to repeat the evolutions in full 3D without axisymmetry; the paper itself notes that axisymmetry suppresses toroidal-field instabilities, so non-axisymmetric runs would reveal whether the linear relations survive in more realistic configurations.
  • The same ratio-contour method could be applied to poloidal or twisted-torus magnetic fields, potentially separating field-strength effects from field-geometry effects on mode frequencies.
  • The opposite slope directions for f_F and f_2f suggest that measuring both frequencies individually, rather than only their ratio, could break the residual degeneracy between rotation and magnetization.
  • The fixed baryonic mass (1.506 M_sun) means the quantitative slopes are not yet universal; extending the survey toward 2 M_sun merger-remnant masses is a direct next step that the paper flags as necessary.

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

3 major / 5 minor

Summary. This paper studies the fundamental l=0 (f_F) and l=2 (2f) oscillation modes of rotating neutron stars with a purely toroidal magnetic field, using XNS equilibrium models and 2D axisymmetric GRMHD evolutions with Gmunu. Five sequences with toroidal magnetization constants K_m=0.5,1.0,1.5,2.0,2.5 and a fixed baryonic mass are evolved, and the mode frequencies are fit as quasi-linear functions of compactness M/R and T/|W|. The authors find that the slopes of these fits depend on K_m, and they construct a contour map of the frequency ratio f_2f/f_F versus T/|W| and B_max, claiming that measuring this ratio enables inference of both quantities. Differentially rotating models with K_m=0.5 and 2.5 are also evolved, finding deviations of at most a few percent from the uniform-rotation fits. The paper includes detailed model tables in Appendix A.

Significance. If the main result holds, this is the first systematic general-relativistic survey of the combined effects of rotation and a toroidal magnetic field on the fundamental f and 2f modes, and it would be a useful step toward gravitational-wave asteroseismology of magnetized, rotating neutron stars. The manuscript is transparent: the equilibrium tables are provided, the fit residuals are quoted (≲1–2%), and established open-source codes (XNS, Gmunu) are used. The quantitative quasi-linear relations themselves are plausible and supported by the displayed data. However, the paper's central inference claim—that one frequency ratio gives both T/|W| and B_max—is not supported by the evidence presented, and the 2D axisymmetric setup suppresses the instabilities known to affect purely toroidal fields. These issues affect the abstract and conclusions and require revision.

major comments (3)
  1. [Section V, Fig. 3] The claim that measuring f_2f/f_F enables inference of both T/|W| and B_max is underdetermined. f_2f/f_F is one scalar, so its level sets in the (T/|W|, B_max) plane are generically one-dimensional curves, not isolated points. The figure itself shows e.g. the 1.32 contour appearing on multiple branches, and each dash-dotted contour spans broad ranges of both axes. Without an additional constraint or prior relating rotation and field strength, a measured ratio leaves a continuum of acceptable parameter pairs. The abstract and Section VII therefore overstate what Fig. 3 establishes. The authors should either reformulate the result as a joint constraint (a curve in the plane) or demonstrate with a proper inference treatment, including measurement noise and model uncertainty, that the ratio can actually localize both parameters.
  2. [Section II.A and Section VII] As the paper states, purely toroidal magnetic fields are generally unstable, and the magnetic instabilities are suppressed by imposing 2D axisymmetry. The simulated frequencies are therefore those of an artificially stabilized configuration. If instabilities grow in 3D or non-axisymmetric modes dominate the real signal, the computed f_F and f_2f, and hence any inference based on their ratio, would not describe the actual neutron-star signal. This is acknowledged as a limitation in the text, but the abstract and conclusions still make the unqualified claim that rotational and magnetic properties can be inferred from fundamental modes. To make the astrophysical claim load-bearing, the authors should either add 3D simulations (or cite existing 3D evidence that the relevant modes survive) or clearly restrict the claim to the stabilized, axisymmetric configuration.
  3. [Section II.A and Section VII] The entire study uses a single baryonic mass M_0=1.506 and a single polytropic EOS (K=100, γ=2). The authors correctly note that the linear-relation coefficients and the inference map would change for other masses and more realistic EOSs. Nevertheless, the abstract's broad statement that this work shows neutron-star rotational and magnetic properties can be inferred from fundamental modes is premature. Since astrophysical neutron stars have a range of masses and unknown EOSs, a frequency-ratio measurement cannot be mapped to T/|W| and B_max without knowing (or marginalizing over) the mass and EOS. The authors should either extend the study to include mass/EOS variation or explicitly restrict the title/abstract/conclusions to the fixed-mass, polytropic models considered here.
minor comments (5)
  1. [Section V, first paragraph] Grammatical error: "We constructed this plot is constructed by the multiquadric radial basis function interpolation..." should read "This plot is constructed...".
  2. [Section VII, first paragraph] Typo: "differntial rotations" should be "differential rotation".
  3. [Equations (6)-(9)] The fits are described as "pred" and "predictions," but they are in-sample linear regressions of the same simulation data used to construct them. Consider renaming these to "fit" or "empirical relation" and, ideally, reporting the fitted coefficients with uncertainties rather than only displaying them in figures.
  4. [Section V / Conclusions] The error estimate of ≲1% for the frequency ratio, and the corresponding ≲1% inference error, is based on an assumed post-merger measurement accuracy from third-generation detectors. This is speculative; the text acknowledges a proper analysis is needed. It would be clearer to present this as an illustrative estimate, not a result.
  5. [Appendix A] Some sequences have five models while TK5U has only four. Consider adding a fifth TK5U model for consistency, or state explicitly why the sequence terminates earlier.

Circularity Check

0 steps flagged

No significant circularity; the fitted relations are presented as empirical fits and the differential-rotation comparison provides an out-of-sample test.

full rationale

The paper's central content is a set of numerical simulations. Equations (6)-(9) are linear regressions of the simulated fundamental-mode frequencies against M/R and T/|W|; they are descriptive fits of the same data they summarize, so calling them 'predictions' is a labeling choice rather than an independent prediction. The paper does not use those fits to claim validation on the same data. Section VI does make a genuine out-of-sample prediction: fits from uniformly rotating models are compared with new simulations of differentially rotating stars, and the small deviations (f_F deviations ≲2.5%, f_2f deviations ≲5%) support the relations' usefulness. The contour plot in Fig. 3 is built by interpolating the same simulated data points, and using it to map f_2f/f_F back to (T/|W|, B_max) is an empirical inversion, not a circular derivation; the underdetermination noted by the skeptic is an identifiability limitation, not circularity. Self-citations to prior work by the same authors (e.g., [54], [59]) supply baselines and prior relations that are independent of the current simulations and are not used to force the present conclusions. No step in the derivation reduces to its own inputs by definition.

Axiom & Free-Parameter Ledger

4 free parameters · 4 axioms · 0 invented entities

The central relations rest on hand-chosen model parameters (K_m, M_0, m, A-tilde) and domain assumptions about stability, EOS, metric approximation, and rotation law. No genuinely new physical entity is introduced, but the calibration grid is narrow, which limits the generality of the claimed inference.

free parameters (4)
  • Toroidal magnetization constant K_m = 0.5, 1.0, 1.5, 2.0, 2.5
    Chosen by hand to set maximum field strengths B_max around 10^17 G; the fitted slopes are presented against this parameter, which is not an independently observed quantity.
  • Baryonic rest mass M_0 = 1.506 in solar masses
    Fixed for all models to allow direct comparison with earlier sequences; the paper notes slopes and intercepts would change if mass were varied.
  • Toroidal magnetization index m = 1
    All models share m=1; the field profile and resulting mode frequencies could depend on this index, so it is a chosen model input rather than an inferred quantity.
  • Differential rotation parameter A-tilde = 1.0
    Chosen as a representative value for the j-constant rotation law in Section VI; the conclusion about differential rotation is tied to this choice.
axioms (4)
  • domain assumption Purely toroidal magnetic fields in axisymmetric equilibrium remain stable enough over 20 ms for mode frequencies to be meaningful
    The paper explicitly suppresses magnetic instabilities by imposing 2D axisymmetry, and cites literature indicating toroidal configurations are generally unstable. This is a load-bearing modeling assumption, not a proven property of real neutron stars.
  • domain assumption A polytropic equation of state with K=100 and gamma=2 adequately represents neutron star matter for this mode study
    The same polytropic EOS is used for initial data and evolution; no microphysical, thermal, or composition effects are included, and the authors list realistic EOS as future work.
  • domain assumption The conformally flat condition (CFC) in Gmunu is sufficiently accurate for fundamental-mode frequencies
    The metric is solved under the CFC approximation; the paper relies on prior code validation but does not provide a convergence or accuracy check for the specific modes studied here.
  • domain assumption The j-constant differential rotation law with A-tilde=1 is representative of astrophysical differential rotation
    Section VI uses this law for only two sequences; the authors acknowledge that more realistic rotation laws may change quantitative conclusions.

pith-pipeline@v1.3.0-alltime-deepseek · 21973 in / 14474 out tokens · 163925 ms · 2026-08-04T18:06:33.440638+00:00 · methodology

0 comments
read the original abstract

Electromagnetic and gravitational-wave signals from neutron stars are shaped by rapid rotation and strong magnetic fields. Determining these properties is essential to interpret such signals, but current measurements are limited: rotation estimates rely on electromagnetic detections and assume uniform rotation, while inferring interior magnetic fields remains ambiguous due to a lack of direct observations. Measuring the excited fundamental modes of neutron stars in gravitational-wave signals offers a promising solution, as these modes encode information about stellar composition, structure, and dynamics. Previous studies have examined the individual effects of rotation and magnetic fields on these modes, identifying magnetic suppression and establishing linear relations for the frequencies of the fundamental $l=0$ quasi-radial mode $f_F$ and $l=2$ quadrupolar mode $f_{^2f}$. However, few have investigated the combined influence of rotation and magnetic fields. Here, for the first time, we consider both rotation and a toroidal magnetic field to construct linear relations for quantifying $f_F$ and $f_{^2f}$, showing that their combined effects can be constrained by detecting these modes. Using 2D axisymmetric simulations, we demonstrate that quasi-linear relations between $f_F$, $f_{^2f}$, stellar compactness $M/R$, and kinetic-to-binding energy ratio $T/|W|$ persist even with a toroidal magnetic field. The slope of these relations depends on the toroidal magnetization constant $K_\mathrm{m}$. Additionally, measuring the frequency ratio $f_{^2f}/f_F$ enables inference of $T/|W|$ and the maximum magnetic field strength $\mathcal{B}_\mathrm{max}$. Lastly, we show that differential rotation causes only minor deviations from predictions for uniform rotation. Thus, this work demonstrates that rotational and magnetic properties of neutron stars can be inferred from their fundamental modes.

Figures

Figures reproduced from arXiv: 2509.10150 by Anson Ka Long Yip, Tjonnie Guang Feng Li.

Figure 1
Figure 1. Figure 1: FIG. 1: Plots of fundamental mode frequencies [PITH_FULL_IMAGE:figures/full_fig_p005_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2: Plots of fundamental mode frequencies [PITH_FULL_IMAGE:figures/full_fig_p007_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3: Contour plot of the frequency ratio between [PITH_FULL_IMAGE:figures/full_fig_p008_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: FIG. 4: Plots of fundamental mode frequencies [PITH_FULL_IMAGE:figures/full_fig_p009_4.png] view at source ↗

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

104 extracted references · 79 linked inside Pith

  1. [1]

    Reisenegger, Magnetic Fields of Neutron Stars: an Overview, inMagnetic Fields Across the Hertzsprung- Russell Diagram, Astronomical Society of the Pacific Conference Series, Vol

    A. Reisenegger, Magnetic Fields of Neutron Stars: an Overview, inMagnetic Fields Across the Hertzsprung- Russell Diagram, Astronomical Society of the Pacific Conference Series, Vol. 248, edited by G. Mathys, S. K. Solanki, and D. T. Wickramasinghe (2001) p. 469, arXiv:astro-ph/0103010 [astro-ph]

    Pith/arXiv arXiv 2001

  2. [2]

    B. P. Abbott, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, K. Ackley, C. Adams, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, G. Allen, A. Allocca, M. A. Aloy, P. A. Altin, A. Am- ato, S. Anand, A. Ananyeva, S. B. Anderson, W. G. An- derson, S. V. Angelova, S. Antier, S. Apper...

    Pith/arXiv arXiv 2020

  3. [3]

    H. T. Janka, K. Langanke, A. Marek, G. Mart ´ ınez- Pinedo, and B. M¨ uller, Theory of core-collapse su- pernovae, Phys. Rep.442, 38 (2007), arXiv:astro- ph/0612072 [astro-ph]

    arXiv 2007

  4. [4]

    Shibata,Numerical Relativity(World Scientific, 2016)

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

    2016

  5. [5]

    Baiotti and L

    L. Baiotti and L. Rezzolla, Binary neutron star merg- ers: a review of Einstein’s richest laboratory, Reports on Progress in Physics80, 096901 (2017), arXiv:1607.03540 [gr-qc]

    Pith/arXiv arXiv 2017

  6. [6]

    Kouveliotou, S

    C. Kouveliotou, S. Dieters, T. Strohmayer, J. van Paradijs, G. J. Fishman, C. A. Meegan, K. Hurley, J. Kommers, I. Smith, D. Frail, and T. Murakami, An X- ray pulsar with a superstrong magnetic field in the soft γ-ray repeater SGR1806 - 20, Nature393, 235 (1998)

    1998

  7. [7]

    Hurley, P

    K. Hurley, P. Li, C. Kouveliotou, T. Murakami, M. Ando, T. Strohmayer, J. van Paradijs, F. Vrba, C. Luginbuhl, A. Yoshida, and I. Smith, ASCA Dis- covery of an X-Ray Pulsar in the Error Box of SGR 1900+14, ApJ510, L111 (1999), arXiv:astro- ph/9811388 [astro-ph]

    arXiv 1900

  8. [8]

    Mereghetti and L

    S. Mereghetti and L. Stella, The Very Low Mass X-Ray Binary Pulsars: A New Class of Sources?, ApJ442, L17 (1995)

    1995

  9. [9]

    Mereghetti, D

    S. Mereghetti, D. Cremonesi, M. Feroci, and M. Tavani, BeppoSAX observations of SGR 1806-20 SAX observa- tions of SGR 1806-20, A&A361, 240 (2000)

    2000

  10. [10]

    van Paradijs, R

    J. van Paradijs, R. E. Taam, and E. P. J. van den Heuvel, On the nature of the ’anomalous’ 6-s X-ray pul- sars, A&A299, L41 (1995)

    1995

  11. [11]

    Kiuchi and S

    K. Kiuchi and S. Yoshida, Relativistic stars with purely toroidal magnetic fields, Phys. Rev. D78, 044045 (2008), arXiv:0802.2983 [astro-ph]

    Pith/arXiv arXiv 2008

  12. [12]

    Kiuchi, K

    K. Kiuchi, K. Kotake, and S. Yoshida, Equilibrium Con- figurations of Relativistic Stars with Purely Toroidal Magnetic Fields: Effects of Realistic Equations of State, ApJ698, 541 (2009), arXiv:0904.2044 [astro-ph.HE]

    Pith/arXiv arXiv 2009

  13. [13]

    Frieben and L

    J. Frieben and L. Rezzolla, Equilibrium models of rel- ativistic stars with a toroidal magnetic field, MNRAS 427, 3406 (2012), arXiv:1207.4035 [gr-qc]

    Pith/arXiv arXiv 2012

  14. [14]

    Bocquet, S

    M. Bocquet, S. Bonazzola, E. Gourgoulhon, and J. No- vak, Rotating neutron star models with a magnetic field., A&A301, 757 (1995), arXiv:gr-qc/9503044 [gr- qc]

    Pith/arXiv arXiv 1995

  15. [15]

    Konno, Moments of inertia of relativistic magnetized stars, A&A372, 594 (2001), arXiv:gr-qc/0105015 [gr- qc]

    K. Konno, Moments of inertia of relativistic magnetized stars, A&A372, 594 (2001), arXiv:gr-qc/0105015 [gr- qc]

    Pith/arXiv arXiv 2001

  16. [16]

    S. S. Yazadjiev, Relativistic models of magnetars: Non- perturbative analytical approach, Phys. Rev. D85, 044030 (2012), arXiv:1111.3536 [gr-qc]

    Pith/arXiv arXiv 2012

  17. [17]

    Bonazzola and E

    S. Bonazzola and E. Gourgoulhon, Gravitational waves from pulsars: emission by the magnetic-field- induced distortion., A&A312, 675 (1996), arXiv:astro- ph/9602107 [astro-ph]

    arXiv 1996

  18. [18]

    R. J. Tayler, Hydromagnetic Instabilities of an Ideally Conducting Fluid, Proceedings of the Physical Society B70, 31 (1957)

    1957

  19. [19]

    R. J. Tayler, The adiabatic stability of stars contain- ing magnetic fields-I.Toroidal fields, MNRAS161, 365 (1973)

    1973

  20. [20]

    Markey and R

    P. Markey and R. J. Tayler, The adiabatic stability of stars containing magnetic fields. II. Poloidal fields, MN- RAS163, 77 (1973)

    1973

  21. [21]

    Markey and R

    P. Markey and R. J. Tayler, The adiabatic stability of stars containing magnetic fields-III. Additional results 12 for poloidal fields, MNRAS168, 505 (1974)

    1974

  22. [22]

    G. A. E. Wright, Pinch instabilities in magnetic stars, MNRAS162, 339 (1973)

    1973

  23. [23]

    Braithwaite and ˚A

    J. Braithwaite and ˚A. Nordlund, Stable magnetic fields in stellar interiors, A&A450, 1077 (2006), arXiv:astro- ph/0510316 [astro-ph]

    arXiv 2006

  24. [24]

    Braithwaite and H

    J. Braithwaite and H. C. Spruit, Evolution of the magnetic field in magnetars, A&A450, 1097 (2006), arXiv:astro-ph/0510287 [astro-ph]

    Pith/arXiv arXiv 2006

  25. [25]

    Braithwaite, Axisymmetric magnetic fields in stars: relative strengths of poloidal and toroidal components, MNRAS397, 763 (2009), arXiv:0810.1049 [astro-ph]

    J. Braithwaite, Axisymmetric magnetic fields in stars: relative strengths of poloidal and toroidal components, MNRAS397, 763 (2009), arXiv:0810.1049 [astro-ph]

    Pith/arXiv arXiv 2009

  26. [26]

    A. G. Suvorov and K. Glampedakis, Magnetic equi- libria of relativistic axisymmetric stars: The impact of flow constants, Phys. Rev. D108, 084006 (2023), arXiv:2309.08071 [gr-qc]

    Pith/arXiv arXiv 2023

  27. [27]

    C. T. Y. Chung and A. Melatos, Stokes tomography of radio pulsar magnetospheres - I. Linear polariza- tion, MNRAS411, 2471 (2011), arXiv:1010.2816 [astro- ph.SR]

    Pith/arXiv arXiv 2011

  28. [28]

    C. T. Y. Chung and A. Melatos, Stokes tomography of radio pulsar magnetospheres - II. Millisecond pul- sars, MNRAS415, 1703 (2011), arXiv:1104.1016 [astro- ph.SR]

    Pith/arXiv arXiv 2011

  29. [29]

    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, A NICER View of PSR J0030+0451: Evidence for a Global-scale Multipolar Magnetic Field, ApJ887, L23 (2019), arXiv:1912.05704 [astro-ph.HE]

    Pith/arXiv arXiv 2019

  30. [30]

    R. C. R. de Lima, J. G. Coelho, J. P. Pereira, C. V. Rodrigues, and J. A. Rueda, Evidence for a Multipolar Magnetic Field in SGR J1745-2900 from X-Ray Light- curve Analysis, ApJ889, 165 (2020), arXiv:1912.12336 [astro-ph.SR]

    Pith/arXiv arXiv 2020

  31. [31]

    B. P. Abbottet al., GW170817: Observation of Grav- itational Waves from a Binary Neutron Star Inspiral, Phys. Rev. Lett.119, 161101 (2017), arXiv:1710.05832 [gr-qc]

    Pith/arXiv arXiv 2017

  32. [32]

    Stergioulas, T

    N. Stergioulas, T. A. Apostolatos, and J. A. Font, Non-linear pulsations in differentially rotating neutron stars: mass-shedding-induced damping and splitting of the fundamental mode, MNRAS352, 1089 (2004), arXiv:astro-ph/0312648 [astro-ph]

    Pith/arXiv arXiv 2004

  33. [33]

    K. D. Kokkotas and N. Stergioulas, Gravitational Waves from Compact Sources, inNew Worlds in Astroparticle Physics: Proceedings of the Fifth International Work- shop, edited by A. M. Mour˜ ao, M. Pimenta, R. Potting, and P. M. S´ a (2006) pp. 25–46, arXiv:gr-qc/0506083 [gr- qc]

    Pith/arXiv arXiv 2006

  34. [34]

    A. G. Pili, N. Bucciantini, and L. Del Zanna, Ax- isymmetric equilibrium models for magnetized neutron stars in General Relativity under the Conformally Flat Condition, MNRAS439, 3541 (2014), arXiv:1401.4308 [astro-ph.HE]

    Pith/arXiv arXiv 2014

  35. [35]

    C. D. Ott, A. Burrows, T. A. Thompson, E. Livne, and R. Walder, The Spin Periods and Rotational Pro- files of Neutron Stars at Birth, ApJS164, 130 (2006), arXiv:astro-ph/0508462 [astro-ph]

    Pith/arXiv arXiv 2006

  36. [36]

    D. J. Price and S. Rosswog, Producing Ultrastrong Mag- netic Fields in Neutron Star Mergers, Science312, 719 (2006), arXiv:astro-ph/0603845 [astro-ph]

    Pith/arXiv arXiv 2006

  37. [37]

    Kiuchi, Y

    K. Kiuchi, Y. Sekiguchi, K. Kyutoku, M. Shibata, K. Taniguchi, and T. Wada, High resolution magne- tohydrodynamic simulation of black hole-neutron star merger: Mass ejection and short gamma ray bursts, Phys. Rev. D92, 064034 (2015), arXiv:1506.06811 [astro-ph.HE]

    Pith/arXiv arXiv 2015

  38. [38]

    Kiuchi, P

    K. Kiuchi, P. Cerd´ a-Dur´ an, K. Kyutoku, Y. Sekiguchi, and M. Shibata, Efficient magnetic-field amplification due to the Kelvin-Helmholtz instability in binary neu- tron star mergers, Phys. Rev. D92, 124034 (2015), arXiv:1509.09205 [astro-ph.HE]

    Pith/arXiv arXiv 2015

  39. [39]

    Aguilera-Miret, D

    R. Aguilera-Miret, D. Vigan` o, F. Carrasco, B. Mi˜ nano, and C. Palenzuela, Turbulent magnetic-field amplifi- cation in the first 10 milliseconds after a binary neu- tron star merger: Comparing high-resolution and large- eddy simulations, Phys. Rev. D102, 103006 (2020), arXiv:2009.06669 [gr-qc]

    Pith/arXiv arXiv 2020

  40. [40]

    Hanauske, K

    M. Hanauske, K. Takami, L. Bovard, L. Rezzolla, J. A. Font, F. Galeazzi, and H. St¨ ocker, Rotational proper- ties of hypermassive neutron stars from binary mergers, Phys. Rev. D96, 043004 (2017), arXiv:1611.07152 [gr- qc]

    Pith/arXiv arXiv 2017

  41. [41]

    Andersson and K

    N. Andersson and K. D. Kokkotas, Towards grav- itational wave asteroseismology, MNRAS299, 1059 (1998), arXiv:gr-qc/9711088 [gr-qc]

    Pith/arXiv arXiv 1998

  42. [42]

    Yoshida and Y

    S. Yoshida and Y. Eriguchi, A Numerical Study of Normal Modes of Rotating Neutron Star Models by the Cowling Approximation, ApJ515, 414 (1999), arXiv:astro-ph/9807254 [astro-ph]

    Pith/arXiv arXiv 1999

  43. [43]

    K. D. Kokkotas, T. A. Apostolatos, and N. Andersson, The inverse problem for pulsating neutron stars: a ‘fin- gerprint analysis’ for the supranuclear equation of state, MNRAS320, 307 (2001), arXiv:gr-qc/9901072 [gr-qc]

    Pith/arXiv arXiv 2001

  44. [44]

    J. A. Font, H. Dimmelmeier, A. Gupta, and N. Ster- gioulas, Axisymmetric modes of rotating relativistic stars in the Cowling approximation, MNRAS325, 1463 (2001), arXiv:astro-ph/0012477 [astro-ph]

    Pith/arXiv arXiv 2001

  45. [45]

    Yoshida, L

    S. Yoshida, L. Rezzolla, S. Karino, and Y. Eriguchi, Frequencies of f-Modes in Differentially Rotating Rel- ativistic Stars and Secular Stability Limits, ApJ568, L41 (2002), arXiv:gr-qc/0112017 [gr-qc]

    Pith/arXiv arXiv 2002

  46. [46]

    J. A. Font, T. Goodale, S. Iyer, M. Miller, L. Rezzolla, E. Seidel, N. Stergioulas, W.-M. Suen, and M. Tobias, Three-dimensional numerical general relativistic hydro- dynamics. II. Long-term dynamics of single relativis- tic stars, Phys. Rev. D65, 084024 (2002), arXiv:gr- qc/0110047 [gr-qc]

    arXiv 2002

  47. [47]

    Benhar, V

    O. Benhar, V. Ferrari, and L. Gualtieri, Gravitational wave asteroseismology reexamined, Phys. Rev. D70, 124015 (2004), arXiv:astro-ph/0407529 [astro-ph]

    Pith/arXiv arXiv 2004

  48. [48]

    Yoshida, S

    S. Yoshida, S. Yoshida, and Y. Eriguchi, R-mode oscilla- tions of rapidly rotating barotropic stars in general rel- ativity: analysis by the relativistic Cowling approxima- tion, MNRAS356, 217 (2005), arXiv:astro-ph/0406283 [astro-ph]

    Pith/arXiv arXiv 2005

  49. [49]

    Dimmelmeier, N

    H. Dimmelmeier, N. Stergioulas, and J. A. Font, Non- linear axisymmetric pulsations of rotating relativistic stars in the conformal flatness approximation, MNRAS 368, 1609 (2006), arXiv:astro-ph/0511394 [astro-ph]

    Pith/arXiv arXiv 2006

  50. [50]

    Kr¨ uger, E

    C. Kr¨ uger, E. Gaertig, and K. D. Kokkotas, Oscilla- tions and instabilities of fast and differentially rotat- ing relativistic stars, Phys. Rev. D81, 084019 (2010), arXiv:0911.2764 [astro-ph.SR]

    Pith/arXiv arXiv 2010

  51. [51]

    Gaertig and K

    E. Gaertig and K. D. Kokkotas, Gravitational wave asteroseismology with fast rotating neutron stars, Phys. Rev. D83, 064031 (2011), arXiv:1005.5228 [astro- 13 ph.SR]

    Pith/arXiv arXiv 2011

  52. [52]

    D. D. Doneva, E. Gaertig, K. D. Kokkotas, and C. Kr¨ uger, Gravitational wave asteroseismology of fast rotating neutron stars with realistic equations of state, Phys. Rev. D88, 044052 (2013), arXiv:1305.7197 [astro- ph.SR]

    Pith/arXiv arXiv 2013

  53. [53]

    C. J. Kr¨ uger and K. D. Kokkotas, Fast Rotating Rel- ativistic Stars: Spectra and Stability without Ap- proximation, Phys. Rev. Lett.125, 111106 (2020), arXiv:1910.08370 [gr-qc]

    Pith/arXiv arXiv 2020

  54. [54]

    A. K. L. Yip, P. Chi-Kit Cheong, and T. G. F. Li, Universal relations for fundamental modes of ro- tating neutron stars with differential rotations, arXiv e-prints , arXiv:2401.13993 (2024), arXiv:2401.13993 [astro-ph.HE]

    arXiv 2024

  55. [55]

    M. v. Hoven and Y. Levin, Magnetar os- cillations – I. Strongly coupled dynamics of the crust and the core, MNRAS410, 1036 (2010), https://academic.oup.com/mnras/article- pdf/410/2/1036/3437530/mnras0410-1036.pdf

    2010

  56. [56]

    Messios, D

    N. Messios, D. B. Papadopoulos, and N. Stergioulas, Torsional oscillations of magnetized relativistic stars, MNRAS328, 1161 (2001), arXiv:astro-ph/0105175 [astro-ph]

    Pith/arXiv arXiv 2001

  57. [57]

    Sotani and K

    H. Sotani and K. D. Kokkotas, Alfv´ en polar oscilla- tions of relativistic stars, MNRAS395, 1163 (2009), arXiv:0902.1490 [astro-ph.HE]

    Pith/arXiv arXiv 2009

  58. [58]

    Gabler, P

    M. Gabler, P. Cerd´ a-Dur´ an, N. Stergioulas, J. A. Font, and E. M¨ uller, Magnetoelastic oscillations of neutron stars with dipolar magnetic fields, MNRAS421, 2054 (2012), arXiv:1109.6233 [astro-ph.HE]

    Pith/arXiv arXiv 2054

  59. [59]

    M. Y. Leung, A. K. L. Yip, P. C.-K. Cheong, and T. G. F. Li, Oscillations of highly magnetized non- rotating neutron stars, Communications Physics5, 334 (2022), arXiv:2303.05684 [astro-ph.HE]

    Pith/arXiv arXiv 2022

  60. [60]

    A. K. L. Yip, P. C.-K. Cheong, and T. G. F. Li, Forma- tion of a magnetized hybrid star with a purely toroidal field from phase-transition-induced collapse, MNRAS 534, 3612 (2024), arXiv:2303.16820 [astro-ph.HE]

    Pith/arXiv arXiv 2024

  61. [61]

    A. K. L. Yip, P. C.-K. Cheong, and T. G. F. Li, Grav- itational wave signatures from the phase-transition- induced collapse of a magnetized neutron star, Phys. Rev. D112, 043035 (2025), arXiv:2305.15181 [astro-ph.HE]

    Pith/arXiv arXiv 2025

  62. [62]

    S. K. Lander, D. I. Jones, and A. Passamonti, Oscilla- tions of rotating magnetized neutron stars with purely toroidal magnetic fields, MNRAS405, 318 (2010), arXiv:0912.3480 [astro-ph.SR]

    Pith/arXiv arXiv 2010

  63. [63]

    S. K. Lander and D. I. Jones, Oscillations and instabili- ties in neutron stars with poloidal magnetic fields, MN- RAS412, 1730 (2011), arXiv:1010.0614 [astro-ph.SR]

    Pith/arXiv arXiv 2011

  64. [64]

    P. C.-K. Cheong, L.-M. Lin, and T. G. F. Li, Gmunu: toward multigrid based Einstein field equa- tions solver for general-relativistic hydrodynamics sim- ulations, Classical and Quantum Gravity37, 145015 (2020), arXiv:2001.05723 [gr-qc]

    Pith/arXiv arXiv 2020

  65. [65]

    P. C.-K. Cheong, A. T.-L. Lam, H. H.-Y. Ng, and T. G. F. Li, Gmunu: paralleled, grid-adaptive, general- relativistic magnetohydrodynamics in curvilinear ge- ometries in dynamical space-times, MNRAS508, 2279 (2021), arXiv:2012.07322 [astro-ph.IM]

    Pith/arXiv arXiv 2021

  66. [66]

    P. C.-K. Cheong, D. Y. T. Pong, A. K. L. Yip, and T. G. F. Li, An Extension of Gmunu: General- relativistic Resistive Magnetohydrodynamics Based on Staggered-meshed Constrained Transport with Ellip- tic Cleaning, ApJS261, 22 (2022), arXiv:2110.03732 [astro-ph.IM]

    Pith/arXiv arXiv 2022

  67. [67]

    Paschalidis, W

    V. Paschalidis, W. E. East, F. Pretorius, and S. L. Shapiro, One-arm spiral instability in hypermassive neutron stars formed by dynamical-capture binary neu- tron star mergers, Phys. Rev. D92, 121502 (2015), arXiv:1510.03432 [astro-ph.HE]

    Pith/arXiv arXiv 2015

  68. [68]

    H. H.-Y. Ng, P. C.-K. Cheong, L.-M. Lin, and T. G. F. Li, Gravitational-wave Asteroseismology with f-modes from Neutron Star Binaries at the Merger Phase, ApJ 915, 108 (2021), arXiv:2012.08263 [astro-ph.HE]

    Pith/arXiv arXiv 2021

  69. [69]

    A. K. L. Yip, M. Y. Leung, P. C.-K. Cheong, and T. G. F. Li, Dynamics and gravitational wave signatures of highly magnetized compact stars, PoSICRC2023, 1518 (2023)

    2023

  70. [70]

    P. C.-K. Cheong, F. Foucart, M. D. Duez, A. Of- fermans, N. Muhammed, and P. Chawhan, Energy- dependent and Energy-integrated Two-moment General-relativistic Neutrino Transport Simulations of a Hypermassive Neutron Star, ApJ975, 116 (2024), arXiv:2407.16017 [astro-ph.HE]

    Pith/arXiv arXiv 2024

  71. [71]

    P. C.-K. Cheong, N. Muhammed, P. Chawhan, M. D. Duez, F. Foucart, L. E. Kidder, H. P. Pfeiffer, and M. A. Scheel, High angular momentum hot differen- tially rotating equilibrium star evolutions in confor- mally flat spacetime, Phys. Rev. D110, 043015 (2024), arXiv:2402.18529 [astro-ph.HE]

    Pith/arXiv arXiv 2024

  72. [72]

    Muhammed, M

    N. Muhammed, M. D. Duez, P. Chawhan, N. Ghadiri, L. T. Buchman, F. Foucart, P. C.-K. Cheong, L. E. Kidder, H. P. Pfeiffer, and M. A. Scheel, Stability of hypermassive neutron stars with realistic rotation and entropy profiles, Phys. Rev. D110, 124063 (2024), arXiv:2403.05642 [gr-qc]

    Pith/arXiv arXiv 2024

  73. [73]

    P. C.-K. Cheong, F. Foucart, H. H.-Y. Ng, A. Offer- mans, M. D. Duez, N. Muhammed, and P. Chawhan, Influence of neutrino-electron scattering and neutrino- pair annihilation on hypermassive neutron star, Phys. Rev. D111, 043036 (2025), arXiv:2410.20681 [astro-ph.HE]

    Pith/arXiv arXiv 2025

  74. [74]

    P. C.-K. Cheong, A. Tsokaros, M. Ruiz, F. Ven- turi, J. C. L. Chan, A. K. L. Yip, and K. Ury¯ u, General-relativistic resistive-magnetohydrodynamics simulations of self-consistent magnetized rotating neutron stars, Phys. Rev. D111, 063030 (2025), arXiv:2409.10508 [astro-ph.HE]

    Pith/arXiv arXiv 2025

  75. [75]

    R. W. Romani, D. Kandel, A. V. Filippenko, T. G. Brink, and W. Zheng, PSR J0952-0607: The Fastest and Heaviest Known Galactic Neutron Star, ApJ934, L17 (2022), arXiv:2207.05124 [astro-ph.HE]

    Pith/arXiv arXiv 2022

  76. [76]

    Bucciantini and L

    N. Bucciantini and L. Del Zanna, General relativis- tic magnetohydrodynamics in axisymmetric dynamical spacetimes: the X-ECHO code, A&A528, A101 (2011), arXiv:1010.3532 [astro-ph.IM]

    Pith/arXiv arXiv 2011

  77. [77]

    A. G. Pili, N. Bucciantini, and L. Del Zanna, Gen- eral relativistic neutron stars with twisted magneto- sphere, MNRAS447, 2821 (2015), arXiv:1412.4036 [astro-ph.HE]

    Pith/arXiv arXiv 2015

  78. [78]

    A. G. Pili, N. Bucciantini, and L. Del Zanna, Gen- eral relativistic models for rotating magnetized neutron stars in conformally flat space-time, MNRAS470, 2469 (2017), arXiv:1705.03795 [astro-ph.HE]

    Pith/arXiv arXiv 2017

  79. [79]

    Soldateschi, N

    J. Soldateschi, N. Bucciantini, and L. Del Zanna, Ax- isymmetric equilibrium models for magnetised neutron 14 stars in scalar-tensor theories, A&A640, A44 (2020), arXiv:2005.12758 [astro-ph.HE]

    Pith/arXiv arXiv 2020

  80. [80]

    Herbrik and K

    M. Herbrik and K. D. Kokkotas, Stability analysis of magnetized neutron stars - a semi-analytic approach, MNRAS466, 1330 (2017), arXiv:1511.04290 [astro- ph.SR]

    Pith/arXiv arXiv 2017

Showing first 80 references.