Pith. sign in

REVIEW 4 major objections 6 minor 2 cited by

NuSTAR broadband X-ray observation of EF Eri following its reawakening into a high accretion state

T0 review · 4 major / 6 minor · reviewed 2026-08-11 · deepseek-v4-flash

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

Pith's one-line read Fitting the NuSTAR 3-50 keV spectrum of EF Eri with the MCVSPEC accretion-column model yields a white dwarf mass of (0.55-0.63) solar masses, matching the independent optical measurement and establishing a broadband X-ray route to polar…

desk verdict First NuSTAR look at EF Eri in its new high state gives a WD mass consistent with optical; useful method paper, but the model is unpublished and the numbers need cleaning up. read the letter →

arxiv 2412.11273 v2 pith:7SWAZLND submitted 2024-12-15 astro-ph.HE

Luke W. Filor , Kaya Mori , Gabriel Bridges , Charles J. Hailey , David A. H. Buckley , Gavin Ramsay , Axel D. Schwope , Valery F. Suleimanov
show 2 more authors
Michael T. Wolff Kent S. Wood
This is my paper · ORCID
classification astro-ph.HE
keywords polarsmagneticcataclysmicvariableswhitedwarfmassesaccretioncolumnX-rayspectroscopyNuSTAREFErishock
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

EF Eri, a magnetic white dwarf in a synchronized binary called a polar, spent 26 years in a faint low-accretion state before brightening sharply in late 2022. This paper presents the first hard X-ray observation of that reawakened high state, a joint NuSTAR and NICER campaign. The paper's central claim is that fitting the 3-50 keV NuSTAR spectrum with a one-dimensional accretion-column model, MCVSPEC, yields a white dwarf mass of $M = (0.55{-}0.63)\,M_\odot$, in agreement with the independent optical measurement of $(0.55{-}0.65)\,M_\odot$. Because the hard X-ray continuum directly constrains the post-shock plasma temperature, and because the model ties that temperature to the white dwarf mass through the mass-radius relation, a successful cross-check with optics would establish a broadband X-ray method for weighing white dwarfs in polars. The paper also reports the absence of quasi-periodic oscillations down to a 5% amplitude limit near 0.5 Hz, tightening earlier X-ray QPO constraints.

What carries the argument

The load-bearing object is MCVSPEC, a one-dimensional radiatively cooling accretion-column model for magnetic cataclysmic variables. For a given white dwarf mass $M$, magnetic field $B$, bolometric luminosity $L$, and fractional accretion area $f$, it integrates the coupled continuity, momentum, and energy equations along the column from the standoff shock down to the white dwarf surface, producing density and temperature profiles in a one-temperature treatment. The emergent spectrum is computed by integrating collisionally ionized plasma emissivity (APEC) along the column, with cyclotron cooling included and with WD surface reflection implemented through the reflect model; the reflection scaling factor $r_{\rm ref} = 1 - \sqrt{1 - 1/(1+h_s/R)^2}$ is recomputed from the shock height in each iteration until the height and the reflected Compton hump are consistent. The model converts the assumed mass to radius via the Nauenberg mass-radius relation and computes the accretion rate from $\dot{M} = L/(GM/R)$, which, divided by $4\pi R^2 f$, gives the specific accretion rate $\dot{m}$ that sets the column structure. The central fit parameter is $M$, with $f$ and $Z$ also fitted, and the paper's iterative self-consistency scheme keeps only initial masses $M_i$ that return a best-fit mass $M_f$ matching $M_i$ within errors.

What would settle it

Rerun the MCVSPEC fit to the same NuSTAR spectrum with the accretion area cap removed and $f$ left free, and check whether the best-fit white dwarf mass moves outside $(0.55{-}0.63)\,M_\odot$; alternatively, measure EF Eri's mass independently from a future eclipse, gravitational redshift, or a model-free shock-temperature diagnostic and compare it with the quoted range.

Watch

Extended reading notes

Core claim

The paper claims that the NuSTAR spectrum of EF Eri between 3 and 50 keV, and especially the hard tail above 10 keV, can be reproduced by MCVSPEC only for white dwarf masses in the range $M = (0.55{-}0.63)\,M_\odot$. In the model, the accretion flow falls freely from the donor star and is heated at a standoff shock to $kT_s = \frac{3}{8}\frac{GM\mu m_H}{R + h_s}$, so the shock temperature is set by the white dwarf's mass-to-radius ratio. MCVSPEC then solves for the temperature and density structure of the cooling column, includes cyclotron and thermal bremsstrahlung radiation, and self-consistently models X-ray reflection off the white dwarf surface, with the reflection fraction depending on the shock height $h_s$. The fractional accretion area $f$ is capped using the 1993 EUVE blackbody component and a soft X-ray upper limit from the simultaneous NICER observation, which bounds the specific accretion rate $\dot{m}$. The authors argue that in the high accretion state EF Eri sits in a regime where the derived mass is nearly independent of $\dot{m}$, and the resulting mass agrees with the optical radial-velocity result of $(0.55{-}0.65)\,M_\odot$. This is presented as the first MCVSPEC-based white dwarf mass measurement for a polar and as validation of the broadband X-ray approach.

Load-bearing premise

The load-bearing premise is that MCVSPEC's one-temperature, free-fall accretion-column model, together with the specific-accretion-rate bounds imposed by the 1993 EUVE blackbody cap and the NICER soft X-ray upper limit, correctly describes EF Eri's X-ray emission; if the model or either cap is wrong, the derived mass range shifts.

Editorial extensions

If this is right

  • If the method works for EF Eri, NuSTAR broadband spectra of polars in high accretion states can yield white dwarf masses at roughly $0.1\,M_\odot$ precision without requiring optical radial-velocity campaigns.
  • The same MCVSPEC fitting, applied to the ongoing NuSTAR campaign of about 40 polars, could produce a statistically meaningful mass distribution of magnetic white dwarfs in accreting binaries and allow comparison with isolated white dwarfs.
  • Observing polars during high states reduces both statistical error (more hard X-ray photons) and systematic error (the mass enters a saturation regime where it is nearly independent of the specific accretion rate), making high-state observations the preferred target for mass measurements.
  • The null X-ray QPO search, with a 90% upper limit below 5% amplitude at 0.5 Hz, tightens the constraint on accretion-column instability models and on MHD predictions of shock oscillations in low-field polars.
  • EF Eri's derived mass near $0.6\,M_\odot$ places it on the low end of the magnetic cataclysmic variable mass distribution, which bears on how these binaries form and evolve.

Reading between the lines

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

  • The paper freezes the magnetic field at the optical value of 13 MG; a natural extension would leave $B$ free in the fit, using the broadband spectrum to test whether the X-ray emitting region's field differs from the photometric value.
  • The MCVSPEC verification is cited as in preparation; if that verification shows the model is not accurate across a range of independent masses, the EF Eri mass range would need to be re-derived rather than treated as validated.
  • The one-temperature column description is a deliberate simplification; a two-temperature or explicitly multi-fluid treatment might shift masses systematically, especially at low specific accretion rates where the paper itself notes the derived mass is most sensitive to $\dot{m}$.
  • A testable prediction is that other polars caught by ToO triggers shortly after entering high states should show similar hard spectra and mass-saturation behavior, so the method can be checked before more expensive optical mass measurements are made.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 6 minor

Summary. The paper reports the first NuSTAR observation of the polar EF Eri during its 2023 high accretion state, together with simultaneous NICER data. The authors find hard X-ray emission up to 50 keV, a single-peaked folded lightcurve with a reported pulsed fraction, and no X-ray QPOs in the 0.1–100 Hz band, with an upper limit at the historically observed optical QPO frequency. The central result is a white dwarf mass measurement M = (0.55–0.63) solar masses obtained by fitting the NuSTAR 3–50 keV spectrum with the 1-D accretion-column model MCVSPEC, which is presented as the first application of this model to a polar. The derived mass range agrees with an earlier optical measurement of (0.55–0.65) solar masses, and the authors argue that this demonstrates a promising broadband X-ray method for measuring white dwarf masses in polars.

Significance. If the mass measurement is reliable, this paper provides an important proof-of-concept for determining white dwarf masses in magnetic cataclysmic variables from hard X-ray spectra, which would be valuable for the authors' ongoing NuSTAR survey of polars. The observational dataset is unique: a bright high-state observation of a historically important polar after a 26-year low state, with good photon statistics up to 50 keV and a concurrent soft X-ray observation that helps bound the accretion area. The paper includes a transparent self-consistency loop, standard QPO upper-limit simulations, and an explicit cross-check against an independent optical mass measurement. These strengths are accompanied by significant caveats: the central model MCVSPEC is only cited as being verified in an unpublished work, the one-temperature assumption is not checked at the relevant accretion-rate boundary, and some reported numbers are internally inconsistent. The significance of the method therefore remains conditional on resolving these issues.

major comments (4)
  1. [§5.1, §5.2.4] The mass measurement rests entirely on the MCVSPEC model, but its description is abbreviated and its verification is only cited as 'Bridges et al., in preparation.' A referee cannot assess whether the model's cooling physics, reflection treatment, or numerical implementation are correct, nor whether the claimed validation against independent white dwarf masses actually supports the accuracy of the mass inference. Please provide a full model description or an appendix with the governing equations and key assumptions, and either make the verification results available (e.g., a submitted paper, a detailed table of comparison systems) or describe them explicitly. Without this, the central claim is not reproducible.
  2. [§5.1, §5.2.4] MCVSPEC is described as solving a one-temperature formulation, and the shock temperature formula kTs = 3/8 GM mu mH/(R+hs) gives the ion temperature immediately behind the shock, while the observed X-rays are emitted by electrons. At the lower-bound specific accretion rate mdot = 0.84 g cm^-2 s^-1, the paper itself reports hs/R = 6.9%, a regime away from the saturation limit. At the implied post-shock densities (n ~ 10^15 cm^-3), the electron-ion Coulomb equilibration time can be comparable to or longer than the bremsstrahlung cooling time (the latter is quoted as ~3 s in §6.1 for these conditions). If the electrons remain cooler than the ions, the observed NuSTAR spectrum would require a higher ion shock temperature and hence a higher white dwarf mass than the one-temperature fit returns. Please estimate the ratio of equilibration time to cooling time at the derived post-shock conditions, or run a two-temperature version of the model, or otherwise quantify the systematic bias on M from incomplete electron-ion coupling.
  3. [§5.2.4] The final quoted mass range M = (0.55–0.63) solar masses is the set of initial mass values Mi that are self-consistent under the iterative grid search (Mi ≈ Mf within errors), rather than a conventional confidence interval from the spectral fits. The statistical errors in Table 3 are only ±0.01 solar masses, so the breadth of the range appears to come from the spread of best-fit masses across the allowed mdot range. Please clarify how the reported interval is constructed (e.g., as the union of self-consistent Mi values with their individual statistical errors) and, if possible, present a more standard analysis such as a joint confidence region in the M–mdot plane that would allow the reader to interpret the quoted range as a confidence interval.
  4. [§5.2.1, §5.2.2] The cap on the fractional accretion area f is derived from the assumption that the 1993 EUVE blackbody (kTBB = 19.4 eV) and its luminosity LBB are representative of the 2023 high state. If the current-epoch soft X-ray blackbody were cooler, weaker, or absent, the maximum allowed normalization K and hence fmax would change, which in turn would alter the lower bound on mdot and shift the upper end of the mass range (the mdot = 0.84 g cm^-2 s^-1 case gives Mf = 0.62 solar masses). Please quantify how sensitive the final mass range is to the assumed kTBB and LBB, or show that the NICER data alone place a comparable constraint on the blackbody normalization without relying on the 1993 measurement.
minor comments (6)
  1. [Abstract; §3.3] The abstract states a '~65% spin modulation' for the folded 3–50 keV lightcurve, but §3.3 reports a pulsed fraction of 50.4 ± 0.8% computed from the same data. These numbers should be reconciled, or the definition of the modulated fraction should be stated explicitly in both places.
  2. [Abstract; §3.1; §6.1] The QPO amplitude upper limit is quoted as '<5%' in the abstract and §6.1 for nu = 0.5 Hz, but §3.1 reports 'A < 7%' for the same frequency from the simulation. Similarly, §3.1 gives A < 80% at 10 Hz while §6.1 gives A < 140%. Please correct these inconsistencies and state the simulation parameters (including the quality factor Q range) used for each limit.
  3. [Table 3] Table 3's caption says the fits assume Mi = 0.57 solar masses, while the text and Figure 9 describe Mi = 0.62 solar masses; this should be corrected. In addition, the row labeled 'f [g cm^-2 s^-1]' lists values of 4.6e-4 and 3.1e-6, which are inappropriate units for the fractional accretion area f (a dimensionless quantity); the specific accretion rate mdot is already listed in its own row in g cm^-2 s^-1.
  4. [§5.2.3] The text states that the shaded region corresponds to mdot >= 0.2 g cm^-2 s^-1, but the minimum specific accretion rate was calculated earlier in the same section as mdot = 0.18 g cm^-2 s^-1. Please make these values consistent or explain the difference.
  5. [§3.3] The paper notes that the asymmetry of the pulse profile cannot be explained by visibility changes, yet it proceeds to fit a visibility-only model to derive the magnetic colatitude (17.5°). This is at least confusing and should be clarified, for example by stating that the visibility model is used only to match the overall pulsed fraction while the asymmetry is attributed to an additional, unspecified effect.
  6. [References] The reference list contains duplicate entries for Beardmore & Osborne (1997), with slightly different volume/page formatting. Please consolidate.

Circularity Check

1 steps flagged · score 4.0 of 10

MCVSPEC mass is a fit with an independent optical cross-check; the main circularity flag is the unpublished same-group verification of MCVSPEC.

  1. self citation load bearing [Section 5.1 (X-ray spectral model description)]
    "The MCVSPEC model is fully implemented in XSPEC and verified against a handful of mCVs with independent WD mass measurements (Bridges et al. in preparation). Hence, our baseline spectral model for polars is tbabs*(MCVSPEC+gauss), which takes into account both the primary accretion column and secondary X-ray reflection emission self-consistently."

    The paper derives the WD mass by fitting the MCVSPEC model to NuSTAR data, so the model's accuracy is the load-bearing premise of the mass measurement. The only validation offered for that premise is a citation to 'Bridges et al. in preparation', a manuscript by coauthor Gabriel Bridges and collaborators that is not publicly available for inspection. The model's one-temperature accretion-column physics is therefore accepted on the authority of the same group's unpublished work rather than on an independently checkable result. This is a self-citation chain supporting the central measurement tool. The paper is not fully circular because the fitted mass is subsequently compared with the independent optical mass from Schwope & Christensen (2010), which provides external post-hoc support.

full rationale

The central WD mass is obtained by fitting MCVSPEC to the NuSTAR spectrum, so it is a measured/fitted parameter rather than a prediction from first principles; calling it a 'measurement' is appropriate and does not constitute a fitted-input-called-prediction circularity. The self-consistency iteration in Section 5.2.4 is a fixed-point condition on the initial mass Mi and the fitted mass Mf, not a circular reduction, because Mf is freely fitted at each step. The one-temperature shock model and the electron-ion coupling assumption are potential sources of systematic bias, but they are model limitations rather than instances of derivation-by-definition. The only concrete circularity concern is the reliance on 'Bridges et al. in preparation' for validation of MCVSPEC, which is a same-group, unpublished citation that is load-bearing for the credibility of the mass-measurement method. Because the final result is also checked against an independent optical mass measurement and the spectral fit itself has external content, the paper is only partially dependent on that self-citation chain.

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

The mass measurement rests on six effective free parameters and six axioms, mostly standard CV accretion physics plus two ad hoc carryovers from 1993 data and one unpublished model verification.

free parameters (6)
  • WD mass M = 0.55-0.63 M_sun
    Principal fit parameter in MCVSPEC; range from fitting two extreme mdot values (0.84 and 120 g cm^-2 s^-1).
  • Fractional accretion area f = 4.6e-4 (Mi=0.62 case); 3.1e-6 (mdot_high case)
    Constrained from maximum blackbody normalization allowed by NICER, using kTBB=19.4 eV from EUVE; sets mdot lower bound.
  • Abundance Z = 0.21+0.03-0.04
    Fitted with linked APEC and reflect abundances in MCVSPEC.
  • Flux normalization = not stated
    Fitted normalization of MCVSPEC to NuSTAR count rate.
  • Specific accretion rate mdot = 0.84 and 120 g cm^-2 s^-1
    Systematic parameter; the two extreme values bracket the allowed range and define the reported mass interval.
  • Bolometric luminosity L = 3.26e32 erg/s
    Assembled from NuSTAR bremsstrahlung, g-band-derived cyclotron flux, and 1993 EUVE blackbody assumption; used to set Mdot via Mdot = L/(GM/R).
assumptions (6)
  • standard math Nauenberg (1972) WD mass-radius relation used to derive R from M.
    Invoked in Section 5.1 to convert M to R; standard but unproved in this paper.
  • domain assumption Free-fall from the secondary's Roche lobe to the stand-off shock: v_ff = sqrt(2GM/(R+hs)).
    Assumed in Section 5.1, valid for polars without accretion disks; Doppler tomography cited in support.
  • standard math Stand-off shock temperature kTs = 3/8 GM mu mH / (R+hs) under one-temperature assumption.
    Standard Rankine-Hugoniot result used in Section 5.1.
  • domain assumption One-temperature radiative cooling by thermal bremsstrahlung and cyclotron emission with reflecting WD surface; reflection scaling r_ref = 1 - sqrt(1 - 1/(1+hs/R)^2).
    Core of MCVSPEC polar model described in Section 5.1; not independently validated here.
  • ad hoc to paper 1993 EUVE blackbody (kTBB=19.4 eV) still represents the 2023 high-state blackbody; LBB assumed unchanged.
    Used in Sections 5.2.1-5.2.2 to compute Lbol and cap f; unverified because NICER cannot see below 0.3 keV well.
  • domain assumption MCVSPEC is verified against independent WD masses as cited to Bridges et al. (in preparation).
    Stated in Section 5.1; the verification is unpublished and code unavailable, so the model's correctness is taken on trust.

how reviews work

0 comments
Cite this review

Pith. "Pith review of NuSTAR broadband X-ray observation of EF Eri following its reawakening into a high accretion state." pith.science (2026). https://pith.science/paper/7SWAZLND

@misc{pith2026241211273,
  author       = {Pith},
  title        = {Pith review of: NuSTAR broadband X-ray observation of EF Eri following its reawakening into a high accretion state},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/7SWAZLND}},
  note         = {Machine review of arXiv:2412.11273}
}
abstract

We present the first NuSTAR X-ray observation of EF Eri, a well-known polar system. The NuSTAR observation was conducted in conjunction with NICER, shortly after EF Eri entered a high accretion state following an unprecedented period of low activity lasting 26 years since 1997. NuSTAR detected hard X-ray emission up to 50 keV with an X-ray flux of $1.2\times10^{-10}$ ergs s$^{-1}$ cm$^{-2}$ ($3\rm{-}50$ keV). Folded X-ray lightcurves exhibit a single peak with $\sim65\%$ spin modulation throughout the $3\rm{-}50$ keV band. We found no evidence of QPO signals at $\nu = 0.1\rm{-}100$ Hz with an upper limit on the QPO amplitude below $5\%$ ($90\%$ CL) at $\nu \sim 0.5$ Hz where the optical QPO was previously detected. Our 1-D accretion column model, called $\texttt{MCVSPEC}$, was fitted to the NuSTAR spectral data, yielding an accurate WD mass measurement of $M = (0.55\rm{-}0.63) M_\odot$. ${\tt MCVSPEC}$ accounts for radiative cooling by thermal bremsstrahlung and cyclotron emission, X-ray reflection off the WD surface, and a previously constrained range of the accretion column area. The derived WD mass range is in excellent agreement with the previous measurement of $M = (0.55\rm{-}0.65) M_\odot$ in the optical band. This demonstrates a combination of broadband X-ray spectral analysis and the ${\tt MCVSPEC}$ model that can be employed in our ongoing NuSTAR observation campaign of other polars to determine their WD masses accurately.

Figures

Figures reproduced from arXiv: 2412.11273 by the authors.

Figure 1
Figure 1. EF Eri’s g-band lightcurve from 11/2022 to 02/2023. EF Eri displayed an optical brightening of several magnitudes, corresponding to increased accretion of material onto the WD surface. This lightcurve was created using the ASASSN Sky Patrol Photometry Database (Kochanek et al. 2017; Shappee et al. 2014) [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Deadtime-corrected power density spectra for FPMA (pink) and FPMB (purple). The PDS are averaged from 221 lightcurve segments with a length of 104 s each. The horizontal dashed lines indicate the 3σ detection threshold [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗
Figure 3
Figure 3. Left: NuSTAR FPMA (pink) and FPMB (purple) 3–50 KeV light-curves. A sine wave is overlaid with the ephemeris taken from Schwope & Christensen (2010). Right: Lomb-Scargle periodograms for FPMA and FPMB for 0.23–0.388 mHz. Dashed vertical lines indicate the 81.02 min spin period of EF Eri and the adjacent aliases with the NuSTAR 96 min orbital period. The Horizontal dashed line indicates the 5σ detection threshold. To… view at source ↗
Figures from the paper (7 more)
Figure 4
Figure 4. Figure 4: NuSTAR FPMA (pink) and FPMB (purple) 3–10 and 10–50 keV folded light-curves. Lightcurves are folded on the EF Eri orbital period from Bailey et al. (1982) and phased from the ephemeris in Schwope & Christensen (2010). The folded lightcurves are overlayed with the best-…
Figure 5
Figure 5. Figure 5: Left: NuSTAR spectra and residuals of EF Eri fit with a tbabs*cflux*(APEC) model, yielding a χ 2 statistic of 1.02 with 897 degrees of freedom. Right: NuSTAR spectra and residuals fit with a tbabs*cflux*(APEC+gauss) model, yielding a χ 2 statistic of 0.96 with 896 degr…
Figure 6
Figure 6. Figure 6: Left: X-ray flux in the 3.0–50 keV energy range, separated across 10 phase bins spanning EF Eri’s orbital period of 81 minutes. A significant increase in flux and photon counts is observed between phase bins 0.8−0.2. Right: Comparison of temperature across all phases o…
Figure 7
Figure 7. Figure 7: A flow chart of our iterative procedures of finding a self-consistent solution and deriving the WD mass of EF Eri. The process begins with inputting the bolometric luminosity, independently measured B-field strength and cosine inclination (purple). The main sequence of…
Figure 8
Figure 8. Figure 8: Left: Joint NuSTAR and NICER spectra and residuals of EF Eri fit with a tbabs*(APEC+bbodyrad+gauss+gauss) model, yielding a χ 2 statistic of 0.99 (1054 d.o.f.). Right: Joint NuSTAR and NICER spectra and residuals of EF Eri fit with a tbabs*(APEC+bbodyrad+gauss+gauss) m…
Figure 9
Figure 9. Figure 9: m˙ vs. the best-fit WD mass (Mf ) plots for Mi = 1.2M⊙ (left) and 0.62M⊙ (right) derived from fitting NuSTAR spectra of EF Eri. The red shaded area corresponds to the best-fit mass range, through fitting the MCVSPEC model to the NuSTAR spectra, within the valid ˙m rang…
Figure 10
Figure 10. Figure 10: The NuSTAR spectra and residuals fit with the MCVSPEC model with Mi = 0.62M⊙ and ˙m= 0.84 g cm−2 s −1 (corresponding to f = 4.6 × 10−4 ). The best-fit WD mass is Mf = 0.62 ± 0.01M⊙, making the fit self-consistent as Mf ≈ Mi. The other fit parameters are listed in [PI…

Discussion (0). Continue with ORCID to comment.

Forward citations

Cited by 2 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. X-ray spectroscopy method of white dwarf mass determination in intermediate polars. External systematic uncertainties

    astro-ph.SR 2025-06 conditional novelty 5.0 of 10

    Using heated-envelope white dwarf models in X-ray spectral fitting raises the average intermediate polar white dwarf mass to 0.82 solar masses, matching optical CV values.

  2. The incidence of magnetic cataclysmic variables can be explained by the late appearance of white dwarf magnetic fields

    astro-ph.SR 2025-05 conditional novelty 5.0 of 10

    Assuming white dwarf magnetic fields appear when the white dwarf is 2 to 3 billion years old can reproduce the observed incidence of magnetic cataclysmic variables and predicts that many systems detach near the period...

Reference graph

Works this paper leans on

72 extracted references · 48 canonical work pages · cited by 2 Pith papers

  1. [1]

    1996, in Astronomical Data Analysis Software and Systems V, ASP Conference Series, Vol

    Arnaud, K. 1996, in Astronomical Data Analysis Software and Systems V, ASP Conference Series, Vol. 101, 1996, George H. Jacoby and Jeannette Barnes, eds., p. 17., Vol. 101, 17 Astropy Collaboration, Price-Whelan, A. M., Lim, P. L., et al. 2022, ApJ, 935, 167, doi: 10.3847/1538-4357/ac7c74

    doi:10.3847/1538-4357/ac7c74 1996

  2. [2]

    2015, MaLTPyNT: Quick look timing analysis for NuSTAR data, Astrophysics Source Code Library, record ascl:1502.021

    Bachetti, M. 2015, MaLTPyNT: Quick look timing analysis for NuSTAR data, Astrophysics Source Code Library, record ascl:1502.021

    work page 2015

  3. [3]

    2018, The Astrophysical Journal Letters, 853, L21

    Bachetti, M., & Huppenkothen, D. 2018, The Astrophysical Journal Letters, 853, L21

    work page 2018

  4. [4]

    A., Cook, R., et al

    Bachetti, M., Harrison, F. A., Cook, R., et al. 2015, The Astrophysical Journal, 800, 109 17

    work page 2015

  5. [5]

    2022, StingraySoftware/stingray: Version 1.0, v1.0, Zenodo, doi: 10.5281/zenodo.6394742

    Bachetti, M., Huppenkothen, D., Khan, U., et al. 2022, StingraySoftware/stingray: Version 1.0, v1.0, Zenodo, doi: 10.5281/zenodo.6394742

    work page doi:10.5281/zenodo.6394742 2022

  6. [6]

    J., et al

    Bailey, J., Hough, J., Axon, D. J., et al. 1982, Monthly Notices of the Royal Astronomical Society, 199, 801

    work page 1982

  7. [8]

    P., & Osborne, J

    Beardmore, A. P., & Osborne, J. P. 1997, MNRAS, 286, 77, doi: 10.1093/mnras/286.1.77

    work page doi:10.1093/mnras/286.1.77 1997

  8. [9]

    2018, MNRAS, 474, 1629, doi: 10.1093/mnras/stx2720

    Bera, P., & Bhattacharya, D. 2018, MNRAS, 474, 1629, doi: 10.1093/mnras/stx2720

    doi:10.1093/mnras/stx2720 2018

Show all 72 references
  1. [10]

    2007, Astronomy & Astrophysics, 463, 647

    Beuermann, K., Euchner, F., Reinsch, K., Jordan, S., & G¨ ansicke, B. 2007, Astronomy & Astrophysics, 463, 647

    2007

  2. [11]

    1987, Astrophysical Journal, Part 1 (ISSN 0004-637X), vol

    Beuermann, K., Stella, L., & Patterson, J. 1987, Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 316, May 1, 1987, p. 360-376., 316, 360

    1987

  3. [12]

    1991, Astronomy and Astrophysics (ISSN 0004-6361), vol

    Beuermann, K., Thomas, H.-C., & Pietsch, W. 1991, Astronomy and Astrophysics (ISSN 0004-6361), vol. 246, no. 1, June 1991, p. L36-L39., 246, L36

    1991

  4. [13]

    M., Mouchet, M., Busschaert, C., Falize, E., & Michaut, C

    Bonnet-Bidaud, J. M., Mouchet, M., Busschaert, C., Falize, E., & Michaut, C. 2015, A&A, 579, A24, doi: 10.1051/0004-6361/201425482

    2015 doi

  5. [14]

    K., Harrison, T

    Campbell, R. K., Harrison, T. E., & Kafka, S. 2008a, ApJ, 683, 409, doi: 10.1086/589179

    doi

  6. [15]

    Howell, S. B. 2008b, ApJ, 672, 531, doi: 10.1086/523632

    doi

  7. [16]

    1978, Monthly Notices of the Royal Astronomical Society, vol

    Cooke, B., Ricketts, M., Maccacaro, T., et al. 1978, Monthly Notices of the Royal Astronomical Society, vol. 182, Feb. 1978, p. 489-515. Research supported by the Science Research Council., 182, 489

    1978

  8. [17]

    1990, Space Science Reviews, 54, 195

    Cropper, M. 1990, Space Science Reviews, 54, 195

    1990

  9. [18]

    1999, Monthly Notices of the Royal Astronomical Society, 306, 684 de Martino, D., Bernardini, F., Mukai, K., Falanga, M., &

    Cropper, M., Wu, K., Ramsay, G., & Kocabiyik, A. 1999, Monthly Notices of the Royal Astronomical Society, 306, 684 de Martino, D., Bernardini, F., Mukai, K., Falanga, M., &

    1999

  10. [19]

    2020, Advances in Space Research, 66, 1209

    Masetti, N. 2020, Advances in Space Research, 66, 1209

    2020

  11. [20]

    P., & Beardmore, A

    Done, C., Osborne, J. P., & Beardmore, A. P. 1995, Monthly Notices of the Royal Astronomical Society, 276, 483, doi: 10.1093/mnras/276.2.483

    1995 doi

  12. [21]

    J., Ratzlaff, P

    Drake, J. J., Ratzlaff, P. W., Laming, J. M., & Raymond, J. 2009, ApJ, 703, 1224, doi: 10.1088/0004-637X/703/2/1224

    2009 doi

  13. [22]

    Ferrario, L., de Martino, D., & G¨ ansicke, B. T. 2015, SSRv, 191, 111, doi: 10.1007/s11214-015-0152-0

    2015 doi

  14. [23]

    2024, nifty-ls: Fast and Accurate Lomb-Scargle Periodograms Using a Non-Uniform FFT

    Barnett, A. 2024, nifty-ls: Fast and Accurate Lomb-Scargle Periodograms Using a Non-Uniform FFT. https://arxiv.org/abs/2409.08090

    2024 arXiv

  15. [24]

    J., Mori, K., Perez, K., Canipe, A

    Hailey, C. J., Mori, K., Perez, K., Canipe, A. M., & Hong et al., J. 2016, ApJ, 826, 160, doi: 10.3847/0004-637X/826/2/160

    2016 doi

  16. [25]

    E., Howell, S

    Harrison, T. E., Howell, S. B., Huber, M. E., et al. 2003, The Astronomical Journal, 125, 2609

    2003

  17. [26]

    2014, MNRAS, 438, 2267, doi: 10.1093/mnras/stt2342

    Hayashi, T., & Ishida, M. 2014, MNRAS, 438, 2267, doi: 10.1093/mnras/stt2342

    2014 doi

  18. [27]

    2018, Monthly Notices of the Royal Astronomical Society, 474, 1810 HEASARC

    Hayashi, T., Kitaguchi, T., & Ishida, M. 2018, Monthly Notices of the Royal Astronomical Society, 474, 1810 HEASARC. 2014, HEAsoft: Unified Release of FTOOLS and XANADU, Astrophysics Source Code Library, record ascl:1408.004. http://ascl.net/1408.004

    2018

  19. [28]

    1987, Astrophysical Journal, Part 1 (ISSN 0004-637X), vol

    Imamura, J., Durisen, R., Lamb, D., & Weast, G. 1987, Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 313, Feb. 1, 1987, p. 298-319., 313, 298

    1987

  20. [29]

    N., Steiman-Cameron, T

    Imamura, J. N., Steiman-Cameron, T. Y., & Wolff, M. T. 2000, Publications of the Astronomical Society of the Pacific, 112, 18

    2000

  21. [30]

    N., Wolff, M

    Imamura, J. N., Wolff, M. T., & Durisen, R. H. 1984, ApJ, 276, 667, doi: 10.1086/161654

    1984 doi

  22. [31]

    2020, ApJ, 898, 84, doi: 10.3847/1538-4357/ab9b8d

    Kilic, M., Bergeron, P., Kosakowski, A., et al. 2020, ApJ, 898, 84, doi: 10.3847/1538-4357/ab9b8d

    2020 doi

  23. [32]

    2017, Publications of the Astronomical Society of the Pacific, 129, 104502

    Kochanek, C., Shappee, B., Stanek, K., et al. 2017, Publications of the Astronomical Society of the Pacific, 129, 104502

    2017

  24. [33]

    1982, A&A, 114, L4

    Kuijpers, J., & Pringle, J. 1982, A&A, 114, L4

    1982

  25. [34]

    1979, Astrophysical Journal, Part 2-Letters to the Editor, vol

    Lamb, D., & Masters, A. 1979, Astrophysical Journal, Part 2-Letters to the Editor, vol. 234, Dec. 1, 1979, p. L117-L122., 234, L117

    1979

  26. [35]

    H., Chanmugam, C., & Shaviv, G

    Langer, S. H., Chanmugam, C., & Shaviv, G. 1982, Astrophysical Journal, Part 1, vol. 258, July 1, 1982, p. 289-305., 258, 289

    1982

  27. [36]

    H., Chanmugam, G., & Shaviv, G

    Langer, S. H., Chanmugam, G., & Shaviv, G. 1981, Astrophysical Journal, Part 2-Letters to the Editor, vol. 245, Apr. 1, 1981, p. L23-L26., 245, L23

    1981

  28. [37]

    1987, Astronomy and Astrophysics (ISSN 0004-6361), vol

    Larsson, S. 1987, Astronomy and Astrophysics (ISSN 0004-6361), vol. 181, no. 1, July 1987, p. L15-L17. Research supported by the Naturvetenskapliga Forskningsradet., 181, L15

    1987

  29. [38]

    A., Darbro, W., Elsner, R

    Leahy, D. A., Darbro, W., Elsner, R. F., et al. 1983, ApJ, 266, 160, doi: 10.1086/160766

    1983 doi

  30. [39]

    1990, Monthly Notices of the Royal Astronomical Society, Vol

    Litchfield, S., & King, A. 1990, Monthly Notices of the Royal Astronomical Society, Vol. 247, NO. 2/NOV15, P. 200, 1990, 247, 200

    1990

  31. [40]

    Lomb, N. R. 1976, Ap&SS, 39, 447, doi: 10.1007/BF00648343

    1976 doi

  32. [41]

    Magdziarz, P., & Zdziarski, A. A. 1995, Monthly Notices of the Royal Astronomical Society, 273, 837 18

    1995

  33. [42]

    Mauche, C. W. 1999, in Astronomical Society of the Pacific Conference Series, Vol. 157, Annapolis Workshop on Magnetic Cataclysmic Variables, ed. C. Hellier & K. Mukai, 157, doi: 10.48550/arXiv.astro-ph/9810116

    1999 doi arXiv

  34. [43]

    2022, A&A, 666, A150, doi: 10.1051/0004-6361/202244264

    Mondal, S., Ponti, G., Haberl, F., et al. 2022, A&A, 666, A150, doi: 10.1051/0004-6361/202244264

    2022 doi

  35. [44]

    2017, Publications of the Astronomical Society of the Pacific, 129, 062001, doi: 10.1088/1538-3873/aa6736

    Mukai, K. 2017, Publications of the Astronomical Society of the Pacific, 129, 062001, doi: 10.1088/1538-3873/aa6736

    2017 doi

  36. [45]

    2008, The Astronomer’s Telegram, 1562, 1

    Mukai, K., Walter, F., & Schwope, A. 2008, The Astronomer’s Telegram, 1562, 1

    2008

  37. [46]

    1972, Astrophysical Journal, vol

    Nauenberg, M. 1972, Astrophysical Journal, vol. 175, p. 417, 175, 417

    1972

  38. [47]

    2022, Monthly Notices of the Royal Astronomical Society, 510, 6110

    Pala, A., G¨ ansicke, B., Belloni, D., et al. 2022, Monthly Notices of the Royal Astronomical Society, 510, 6110

    2022

  39. [48]

    F., G¨ ansicke, B

    Pala, A. F., G¨ ansicke, B. T., Breedt, E., Knigge, C., & Hermes et al., J. J. 2020, MNRAS, 494, 3799, doi: 10.1093/mnras/staa764

    2020 doi

  40. [49]

    1981, Astrophysical Journal, Part 1, vol

    Patterson, J., Williams, G., & Hiltner, W. 1981, Astrophysical Journal, Part 1, vol. 245, Apr. 15, 1981, p. 618-623., 245, 618

    1981

  41. [50]

    2000, MNRAS, 314, 403, doi: 10.1046/j.1365-8711.2000.03239.x

    Ramsay, G. 2000, MNRAS, 314, 403, doi: 10.1046/j.1365-8711.2000.03239.x

    2000

  42. [51]

    2004, Monthly Notices of the Royal Astronomical Society, 347, 95

    Priedhorsky, W. 2004, Monthly Notices of the Royal Astronomical Society, 347, 95

    2004

  43. [52]

    2024, ApJ, 976, 115, doi: 10.3847/1538-4357/ad7feb

    Salcedo, C., Mori, K., Bridges, G., et al. 2024, ApJ, 976, 115, doi: 10.3847/1538-4357/ad7feb

    2024 doi

  44. [53]

    Scargle, J. D. 1982, ApJ, 263, 835, doi: 10.1086/160554

    1982 doi

  45. [54]

    2010, Astronomy & Astrophysics, 514, A89

    Schwope, A., & Christensen, L. 2010, Astronomy & Astrophysics, 514, A89

    2010

  46. [55]

    D., Mantel, K.-H., & Horne, K

    Schwope, A. D., Mantel, K.-H., & Horne, K. 1997, arXiv preprint astro-ph/9701094

    1997 arXiv

  47. [56]

    D., Staude, A., Koester, D., & Vogel, J

    Schwope, A. D., Staude, A., Koester, D., & Vogel, J. 2007, Astronomy & Astrophysics, 469, 1027

    2007

  48. [57]

    J., Prieto, J., Grupe, D., et al

    Shappee, B. J., Prieto, J., Grupe, D., et al. 2014, The Astrophysical Journal, 788, 48

    2014

  49. [58]

    W., Heinke, C

    Shaw, A. W., Heinke, C. O., Mukai, K., et al. 2020, MNRAS, 498, 3457, doi: 10.1093/mnras/staa2592

    2020 doi

  50. [59]

    2023, MNRAS, 524, 2431, doi: 10.1093/mnras/stad2043

    Sheng, X., Zhang, L., Blaes, O., & Jiang, Y.-F. 2023, MNRAS, 524, 2431, doi: 10.1093/mnras/stad2043

    2023 doi

  51. [60]

    V., & Werner, K

    Suleimanov, V., Doroshenko, V., Ducci, L., Zhukov, G. V., & Werner, K. 2016, A&A, 591, A35, doi: 10.1051/0004-6361/201628301

    2016 doi

  52. [61]

    F., Doroshenko, V., & Werner, K

    Suleimanov, V. F., Doroshenko, V., & Werner, K. 2019, MNRAS, 482, 3622, doi: 10.1093/mnras/sty2952

    2019 doi

  53. [62]

    E., Plotkin, R

    Szkody, P., Harrison, T. E., Plotkin, R. M., et al. 2006, The Astrophysical Journal, 646, L147

    2006

  54. [63]

    2018, Publications of the Astronomical Society of Japan, 70, 109 Van Box Som, L., Falize, E., Bonnet-Bidaud, J

    Tsujimoto, M., Morihana, K., Hayashi, T., & Kitaguchi, T. 2018, Publications of the Astronomical Society of Japan, 70, 109 Van Box Som, L., Falize, E., Bonnet-Bidaud, J. M., et al. 2018, Mon. Not. Roy. Astron. Soc., 473, 3158, doi: 10.1093/mnras/stx2557 Van Box Som, L., Falize...

    2018 doi

  55. [64]

    2023, The Astrophysical Journal, 954, 138

    Vermette, B., Salcedo, C., Mori, K., et al. 2023, The Astrophysical Journal, 954, 138

    2023

  56. [65]

    G., King, A

    Watson, M. G., King, A. R., & Williams, G. A. 1987, Monthly Notices of the Royal Astronomical Society, 226, 867, doi: 10.1093/mnras/226.4.867

    1987 doi

  57. [66]

    J., & Ramsay, G

    Wheatley, P. J., & Ramsay, G. 1998, in Wild Stars in the Old West, Vol. 137, 446

    1998

  58. [67]

    1980, Publications of the Astronomical Society of the Pacific, 92, 178

    Williams, G., & Hiltner, W. 1980, Publications of the Astronomical Society of the Pacific, 92, 178

    1980

  59. [68]

    1996, Astronomy and Astrophysics, v

    Woelk, U., & Beuermann, K. 1996, Astronomy and Astrophysics, v. 306, p. 232, 306, 232

    1996

  60. [69]

    T., Gardner, J

    Wolff, M. T., Gardner, J. H., & Wood, K. S. 1989, Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 346, Nov. 15, 1989, p. 833-843. Research supported by the US Navy., 346, 833

    1989

  61. [70]

    T., Wood, K

    Wolff, M. T., Wood, K. S., & Imamura, J. N. 1991, Astrophysical Journal, Part 2-Letters (ISSN 0004-637X), vol. 375, July 1, 1991, p. L31-L34. Research supported by

    1991

  62. [71]

    2017, The Golden Age of Cataclysmic Variables and Related Objects IV, 19

    NASA, US Navy, and American Society for Engineering Education., 375, L31 W¨ orpel, H., & Schwope, A. 2017, The Golden Age of Cataclysmic Variables and Related Objects IV, 19

    2017

  63. [72]

    2000, Space Science Reviews, 93, 611, doi: 10.1023/A:1026522914125

    Wu, K. 2000, Space Science Reviews, 93, 611, doi: 10.1023/A:1026522914125

    2000 doi

  64. [73]

    1995, Astrophysical Journal v

    Wu, K., Chanmugam, G., & Shaviv, G. 1995, Astrophysical Journal v. 455, p. 260, 455, 260

    1995

Pith tools

Reviewed August 11, 2026 · model on record in the stance chip above.