{"id":"766afce6-c830-4402-a578-1508cd5755ec","arxiv_id":"2412.11273","paper_version":2,"verdict":"CONDITIONAL","confidence":"MODERATE","novelty_score":6.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":6,"one_line_summary":"First NuSTAR hard X-ray study of EF Eri in its new high state yields a white dwarf mass of 0.55-0.63 solar masses, matching the optical value.","lead":"NuSTAR observed the magnetic white dwarf binary EF Eri right after it woke from a 26-year low state, and the authors used a new accretion column model to weigh the white dwarf at 0.55-0.63 solar masses. The measurement agrees with an earlier optical estimate, suggesting the X-ray method can be used on other similar binaries.","discovery_kind":"new_application","skeptic_critique":{"model":"deepseek-v4-flash","headline":"The WD mass is inferred with a one-temperature shock model; if electron-ion coupling is incomplete at mdot ~ 0.84 g cm^-2 s^-1, the model can bias M low and the quoted range would not be accurate.","rationale":"The reader's weakest assumption already identified MCVSPEC's one-temperature, free-fall column physics as the lynchpin of the mass result, so my concern is not a new area of vulnerability but a sharper statement of the same one. I judge it to be the single most load-bearing issue because the quoted mass range is not an empirical measurement of an observable; it is the output of a spectral model whose key microphysical assumption determines the mapping between photon temperature and WD mass. If complete electron-ion coupling fails at the low-mdot boundary of the allowed range, the bias enters at the level of the basic kTs-M relation, not merely in the secondary caps on mdot. I do not claim this failure is proven; the paper simply contains no check of it. The other potential concerns (unpublished MCVSPEC validation, reliance on the 1993 EUVE blackbody and NICER soft-X-ray upper limit to set f) are real but secondary: the f/L caps mainly set the width of the allowed mdot range, and even a mis-estimated fmax would shift the mass range within a few hundredths of a solar mass, whereas a two-temperature spectrum can move the central mass substantially. The external agreement with the optical mass (0.55-0.65 Msun) is encouraging, but it does not validate the 1-T assumption, and the paper's stated goal of using MCVSPEC on other polars makes the unverified assumption more consequential. The conditional verdict is therefore appropriate: the result is plausible and well-presented, but should not be accepted as a definitive method demonstration until the one-temperature assumption is either verified for this accretion-rate regime or the mass is re-derived with a two-temperature code.","tokens_in":22776,"tokens_out":11102,"duration_ms":111746,"concrete_test":"Run a steady-state two-temperature electron-ion post-shock flow calculation for M = 0.6 Msun, B = 13 MG, and mdot = 0.84 g cm^-2 s^-1, generate the synthetic 3-50 keV spectrum, and fit that spectrum with the one-temperature MCVSPEC model. If the recovered M differs from the input 0.6 Msun by more than about 0.03 Msun (the claimed systematic range), then the one-temperature assumption is load-bearing and the EF Eri mass range must be re-derived with a two-temperature model.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central mass claim inherits MCVSPEC's one-temperature accretion-column assumption. In Section 5.1 the shock temperature is written as kTs = 3/8 GM mu mH/(R+hs), which is the ion temperature immediately behind the shock. The NuSTAR spectrum, however, is emitted by electrons. The polar version of MCVSPEC solves a single-temperature cooling flow, implicitly assuming full electron-ion thermal coupling before the plasma cools radiatively. At the lower-bound specific accretion rate mdot ~ 0.84 g cm^-2 s^-1 derived in Section 5.2.4, the post-shock density is n ~ few x 10^15 cm^-3, and the Coulomb equilibration time is comparable to or longer than the bremsstrahlung cooling time. In that regime the X-ray-emitting electrons can be substantially cooler than the ions, so a given observed spectrum would require a higher ion shock temperature and hence a higher WD mass than the one-temperature MCVSPEC fit returns. If this occurs, the quoted M = (0.55-0.63) Msun range is biased low, and the self-consistency iteration in Section 5.2.4 is testing an incorrect model. The only external validation is a citation to Bridges et al. (in prep.), which is not publicly available; no two-temperature calculation or Coulomb-coupling check is presented in the paper.","agreement_with_reader":"agree"},"referee_report":{"model":"deepseek-v4-flash","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.","tokens_in":23142,"tokens_out":10780,"duration_ms":99230,"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":[{"comment":"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.","section":"§5.1, §5.2.4"},{"comment":"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.","section":"§5.1, §5.2.4"},{"comment":"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.","section":"§5.2.4"},{"comment":"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.","section":"§5.2.1, §5.2.2"}],"minor_comments":[{"comment":"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.","section":"Abstract; §3.3"},{"comment":"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.","section":"Abstract; §3.1; §6.1"},{"comment":"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.","section":"Table 3"},{"comment":"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.","section":"§5.2.3"},{"comment":"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.","section":"§3.3"},{"comment":"The reference list contains duplicate entries for Beardmore & Osborne (1997), with slightly different volume/page formatting. Please consolidate.","section":"References"}],"recommendation":"major_revision","confidential_remarks":"The main concern is that the central mass measurement relies on a model whose verification is unpublished and whose one-temperature assumption is not validated at the relevant parameter boundary. This is a correctness-risk that can be addressed with additional analysis. The paper is otherwise suitable for the journal if the authors provide the requested model details and sensitivity checks. The abstract's inconsistent numbers (pulsed fraction and QPO amplitude) are easily fixed but should be caught before publication."},"author_rebuttal":null,"desk_editor":{"model":"deepseek-v4-flash","letter":"First NuSTAR broadband X-ray observation of EF Eri after its 26-year low state, and the first time the MCVSPEC accretion-column model has been applied to a polar. The central result, M = (0.55–0.63) Msun from fitting the 3–50 keV NuSTAR spectrum, is independently supported by the optical measurement of (0.55–0.65) Msun, and that is the strongest thing in the paper.\n\nThe timing analysis is solid: deadtime-corrected power spectra, sensible simulation-based QPO limits, and a colatitude estimate from the folded light curve. The paper is also honest about the M–mdot degeneracy and lays out the iterative procedure clearly, which is more than many spectral-model papers do.\n\nSoft spots, in rough order of importance.\n\nFirst, there are internal numerical inconsistencies. The abstract quotes ~65% spin modulation, while Section 3.3 computes 50.4 ± 0.8%. The abstract and discussion quote a <5% QPO amplitude limit at 0.5 Hz, while Section 3.1 reports A < 7% at that frequency. These need to be reconciled before submission.\n\nSecond, the WD mass rests on MCVSPEC, whose polar version is only “verified against a handful of mCVs” in Bridges et al. (in preparation). That is not checkable. The self-consistency loop over mdot is a reasonable response to the mass–accretion-rate degeneracy, but it only validates the model against itself. The optical mass is the real anchor; absent that agreement, the result would be much less convincing.\n\nThird, the bolometric luminosity and fractional accretion area are built from a 1993 EUVE blackbody and an extrapolated cyclotron flux. The NICER soft-X-ray cap is a good piece of reasoning, but the systematic budget still omits the EUVE-era blackbody temperature choice and the uncertainty in converting fluxes to luminosities with the Gaia distance.\n\nFourth, the two-temperature concern is worth taking seriously. At the lower-bound mdot ~ 0.84 g/cm2/s, the post-shock density is high enough that Coulomb equilibration may not be complete before bremsstrahlung cooling, so a one-temperature cooling flow could bias the inferred ion shock temperature and hence the mass low. The paper does not address this. Given the optical agreement, the bias is probably modest, but it should be stated as a caveat, or better, quantified with a two-temperature check.\n\nWho is this for: CV/polar observers and anyone using broadband X-ray spectra to measure WD masses. It deserves a serious referee. I would send it out with a request to fix the numerical discrepancies, make the MCVSPEC verification material available or cite a published version, and add a paragraph on electron–ion coupling. The observation and the optical cross-check make the paper well worth engaging.","headline":"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.","tokens_in":23667,"tokens_out":4180,"would_cite":true,"duration_ms":39043,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"deepseek-v4-flash","headline":"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…","keywords":["polars","magnetic cataclysmic variables","white dwarf masses","accretion column","X-ray spectroscopy","NuSTAR","EF Eri","accretion shock"],"falsifier":"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.","tokens_in":22619,"feed_emoji":"🔭","tokens_out":11392,"duration_ms":93760,"temperature":0.7,"pith_summary":"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.","feed_headline":"X-rays weigh a reawakened polar's white dwarf at 0.55-0.63 suns","feed_subtitle":"After a 26-year quiet spell, hard X-rays from EF Eri confirm an optical mass estimate.","key_machinery":"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.","core_discovery":"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.","pith_inferences":["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."],"forward_implications":["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."],"supporting_citations":[{"why":"The MCVSPEC model is verified against magnetic cataclysmic variables with independent white dwarf mass measurements; this verification is the stated basis for trusting the model on EF Eri.","marker":"Bridges et al. (in preparation)"},{"why":"Supplies the independent optical mass range (0.55-0.65) solar masses and the orbital ephemeris used to fold the X-ray light curves.","marker":"Schwope & Christensen (2010)"},{"why":"EUVE blackbody temperature and normalization from 1993 are used to cap the fractional accretion area, which bounds the specific accretion rate.","marker":"Mauche (1999)"},{"why":"Fixes the magnetic field at 13 MG and provides orbital inclination and magnetic colatitude used as MCVSPEC inputs.","marker":"Campbell et al. (2008b)"},{"why":"Makes the case that hard X-ray spectra above 10 keV constrain the shock temperature and hence the white dwarf mass.","marker":"Suleimanov et al. (2019)"},{"why":"Supplies the white dwarf mass-radius relation that converts an assumed mass to radius inside MCVSPEC.","marker":"Nauenberg (1972)"},{"why":"The reflect model for radiation reprocessed off the white dwarf surface is implemented inside MCVSPEC.","marker":"Magdziarz & Zdziarski (1995)"},{"why":"Gives the reflection scaling factor r_ref = 1 - sqrt(1 - 1/(1+h_s/R)^2) that ties the reflection hump to the shock height.","marker":"Tsujimoto et al. (2018)"},{"why":"Provides the method for bounding a possible blackbody component in soft X-ray data, used to derive the maximum accretion area for EF Eri.","marker":"Wörpel & Schwope (2017)"}],"fun_headline_variants":["NuSTAR weighs reawakened EF Eri's white dwarf at 0.55-0.63 suns","26-year quiet spell ends: X-rays pin EF Eri's white dwarf mass","Hard X-rays from EF Eri confirm its white dwarf weight","X-ray spectrum confirms EF Eri's white dwarf mass from optical"],"cache_read_input_tokens":3200,"weakest_assumption_plain":"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.","fun_headline_variants_meta":{"raw":{"variants":["NuSTAR weighs reawakened EF Eri's white dwarf at 0.55-0.63 suns","26-year quiet spell ends: X-rays pin EF Eri's white dwarf mass","Hard X-rays from EF Eri confirm its white dwarf weight","X-ray spectrum confirms EF Eri's white dwarf mass from optical"]},"model":"deepseek-v4-flash","effort":"low","cost_usd":0.000616,"raw_usage":{"total_tokens":2996,"prompt_tokens":1215,"completion_tokens":1781,"prompt_tokens_details":{"cached_tokens":384},"prompt_cache_hit_tokens":384,"prompt_cache_miss_tokens":831,"completion_tokens_details":{"reasoning_tokens":1692}},"tokens_in":831,"tokens_out":1781,"duration_ms":12238,"temperature":1.0,"reasoning_tokens":1692,"cache_read_input_tokens":384,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-08-11T15:07:10.051129+00:00","model_set":{"reader":"deepseek-v4-flash"},"falsifier":"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.","supporting_citations":[{"cited_title":"2010, Astronomy & Astrophysics, 514, A89","cited_arxiv_id":null,"evidence_quote":"Supplies the independent optical mass range (0.55-0.65) solar masses and the orbital ephemeris used to fold the X-ray light curves."},{"cited_title":"EUVE Spectroscopy of Polars","cited_arxiv_id":"astro-ph/9810116","evidence_quote":"EUVE blackbody temperature and normalization from 1993 are used to cap the fractional accretion area, which bounds the specific accretion rate."},{"cited_title":"1972, Astrophysical Journal, vol","cited_arxiv_id":null,"evidence_quote":"Supplies the white dwarf mass-radius relation that converts an assumed mass to radius inside MCVSPEC."},{"cited_title":null,"cited_arxiv_id":null,"evidence_quote":"The reflect model for radiation reprocessed off the white dwarf surface is implemented inside MCVSPEC."},{"cited_title":"2018, Publications of the Astronomical Society of Japan, 70, 109 Van Box Som, L., Falize, E., Bonnet-Bidaud, J","cited_arxiv_id":null,"evidence_quote":"Gives the reflection scaling factor r_ref = 1 - sqrt(1 - 1/(1+h_s/R)^2) that ties the reflection hump to the shock height."}],"review_version":1}