Pith. sign in

REVIEW 3 major objections 3 minor 210 references

Using the donor's surface C/N ratio as a depth gauge, the paper identifies Z Vul as a nearly conservative Case A system where mass transfer stripped only the outer envelope, not the CNO core.

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 →

Z Vul's donor star shows a C/N ratio of 2.14, lacking the deep carbon depletion expected after mass stripping, and the fitted models favor nearly conservative Case A mass transfer.

T0 review reviewed 2026-08-05 challenge →

load-bearing objection The observational core is first-rate, but the abundance-based evolutionary claim doesn't hold up against the paper's own grid. the 3 major comments →

arxiv 2608.03348 v1 pith:LRUWK4HQ submitted 2026-08-04 astro-ph.SR

Unravelling Mass Transfer in Algols from Surface Abundances. I. Z Vulpeculae

classification astro-ph.SR
keywords binaries: eclipsingbinaries: fundamental parametersstars: abundancesstars: evolutionstars: early-typestars: individual: Z VulAlgol binariesmass transfer
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

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

The reading

The paper reports new high-resolution spectra of Z Vul, an Algol-type binary—a close pair in which the originally more massive star now fills its Roche lobe and transfers mass to its companion. From disentangled component spectra it derives photospheric C, N, O, and He abundances: the mass-gaining star is mildly nitrogen-enriched, as expected after accreting CNO-processed material, but the mass-losing donor shows $C/N \approx 2.14$, far above the deeply processed values expected for a core-stripped donor. Matching these abundances against a grid of over three million binary evolution models, the paper argues that Z Vul underwent nearly conservative ($\beta \approx 0.04$–$0.07$) Case A mass transfer (transfer while the original primary is still on the main sequence), with the donor's surface exposing partially processed outer layers rather than the CNO core. The result matters because it shows that surface abundances, read against interior chemical profiles, can distinguish shallow from deep stripping in Algols and constrain the efficiency of mass transfer.

Core claim

The paper establishes that Z Vul's donor, at $2.44\,M_\odot$, has surface $C/N = 2.14^{+0.55}_{-0.44}$, contradicting the classic deep-inversion expectation for stripped Algol donors. STARS evolutionary models fit to the observed masses, radii, and temperatures favor nearly conservative ($\beta \approx 0.04$–$0.07$) Case A transfer, with initial masses $\approx 5.13$ and $\approx 3.73\,M_\odot$ and $P_i \approx 1.37$ d. The models put the donor surface in an intermediate layer of incomplete CNO processing: predicted $C/N \approx 0.39$, and a $0.2\,M_\odot$ shallower strip would yield the observed value near 2. Helium-to-hydrogen stays at $0.408$, its unprocessed value, which the paper reads

What carries the argument

The central object is the $C/N$ ratio at the donor's surface, used as a depth gauge along the stellar interior abundance profile. The paper couples it with the interior $C/N$ and He/H mass-coordinate profiles computed by the STARS binary evolution code, so the measured ratio maps onto a specific stripped mass coordinate. On the gainer, the same framework invokes thermohaline mixing (Kippenhahn et al. 1980) to dilute the accreted CNO-processed material and explain the observed mild nitrogen enrichment.

Load-bearing premise

The conclusion rests on the STARS model's $C/N$ abundance profile being accurate enough that a $0.2\,M_\odot$ shift in the stripped mass—from the measured donor mass $2.44\,M_\odot$ to a slightly larger value—reconciles the predicted donor $C/N$ of $0.39$ with the observed $2.14$; none of the reported grid models at the measured mass reaches $C/N$ above $0.79$.

What would settle it

Compute the STARS grid at the measured donor mass ($2.44\pm0.03\,M_\odot$) with the same physics; if no model in the allowed stripping-depth range of about $0.2\,M_\odot$ produces a surface $C/N$ above $\sim0.8$, the claim of a partially stripped envelope fails. Equivalently, an independent determination of the donor's $C/N$ from ultraviolet lines that yields a ratio below $\sim1.5$ at the same atmospheric parameters would contradict the spectroscopy.

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

If this is right

  • Z Vul is identified as a nearly conservative Case A system, $\beta \approx 0.04$–$0.07$, implying most donor mass remained in the binary.
  • The donor's $C/N \approx 2.14$ pinpoints its stripped surface in the incomplete-CNO zone, so the depth of stripping—not just its existence—is now observable in Algols.
  • The gainer's $C/N \approx 1.70$ after thermohaline mixing shows that accreted abundances are diluted; gainer abundances must be read through a mixing model before use as tracers.
  • An unaltered He/H ratio ($0.408$) on the donor provides a clean diagnostic separating envelope-stripped from core-exposed donors.
  • The method—abundance determination from disentangled spectra plus an evolutionary grid—is transferable to the planned series on other Algols, giving a population-level handle on mass-transfer efficiency.

Where Pith is reading between the lines

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

  • If partial stripping is common among Algol donors, single-star surveys that see nitrogen enhancement with normal helium may be misreading past mass transfer as intrinsic chemical peculiarity; Z Vul provides a donor caught in that intermediate state.
  • The inferred $\beta \approx 0.04$–$0.07$ is tied to the adopted CNO profile; a revised $^{12}\mathrm{C}(p,\gamma)^{14}\mathrm{N}$ rate or additional mixing in the donor would change the stripping-depth calibration and shift the derived efficiency.
  • The same $C/N$-versus-depth mapping could constrain Case A transfer in massive binaries that later merge as black holes, where the final donor's surface abundances are inaccessible but the gainer's pollution pattern after thermohaline mixing may encode the transfer history.
Share X Bluesky LinkedIn Reddit HN

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 / 3 minor

Summary. The paper presents a comprehensive multi-wavelength analysis of the Algol-type binary Z Vul: TESS and ground-based photometry, new high-resolution HERMES spectroscopy, light-curve modelling with spot/attenuation prescriptions, spectral disentangling, iterative atmospheric-parameter and NLTE abundance determinations, and a large grid of Cambridge STARS binary evolutionary models under two angular-momentum-loss regimes (AM1 Fast Case, AM2 Isotropic Re-emission). The authors derive absolute parameters (M1=6.26±0.08 Msun, M2=2.44±0.03 Msun) and abundances for both components, finding a donor C/N abundance ratio of about 2.14 and a gainer ratio of about 1.70. The central interpretive claim is that the absence of a deep C/N inversion in the donor, together with the He/H ratio, indicates nearly conservative (β≈0.04–0.07) Case A mass transfer that stripped the donor only to intermediate layers, not reaching the fully CNO-processed core.

Significance. If the evolutionary interpretation were quantitatively supported, the paper would be an important demonstration that surface C/N ratios in Algol donors can trace partial stripping and constrain the efficiency of mass transfer. The observational component is strong: the light-curve analysis, spectral disentangling, and detailed NLTE abundance work are carried out carefully and produce valuable absolute parameters and abundances for a relatively little-studied Algol. However, the central conclusion is not supported by the model grid. All surviving STARS models in Table E1 predict donor C/N below about 0.8, while the observed value is 2.14+0.55/−0.44, a discrepancy of roughly 0.7 dex and several sigma. The only proposed reconciliation—a 0.2 Msun shallower stripping depth—is ad hoc and directly conflicts with the measured donor mass. The abundance test therefore fails, and the paper's headline claim that CNO abundances confirm near-conservative Case A mass transfer is not established.

major comments (3)
  1. [Section 5, Fig. 8 and Table E1] The grid's best-fit and all surviving models predict donor C/N values far below the observed value. For AM1 the best-fit gives [C/N]d = 0.39±0.12, and for AM2 [C/N]d = 0.38±0.19; the maximum among all listed surviving models in Table E1 is [C/N]d = 0.79. The observed donor C/N is 2.14+0.55/−0.44, which is about 0.7 dex higher. This is a multi-sigma discrepancy and directly contradicts the abstract's statement that 'Constraints from the He and CNO abundances indicate that Z Vul underwent an episode of nearly conservative mass transfer.' The abundances do not provide a constraint in the direction claimed.
  2. [Section 6, final paragraph] The only bridge between the predicted and observed donor C/N is the statement that 'if the donor had been stripped of just 0.2 Msun less mass, the expected surface C/N would perfectly match our spectroscopic value of 2.' This reconciliation is not part of the computed grid and is quantitatively inconsistent with the measured donor mass. A donor stripped by 0.2 Msun less would have a final mass of about 2.64 Msun, compared with the measured M2=2.44±0.03 Msun, a discrepancy of roughly 7σ. The required C/N gradient—a change by a factor of about 5.5 over 0.2 Msun—is not demonstrated from the STARS profiles, and no such model appears in Table E1. The proposed offset is therefore an unsupported, post-hoc adjustment.
  3. [Section 5, Eq. (5)] The χ2 statistic used to identify the best-fitting and surviving models is defined only on masses, radii, and effective temperatures. The C/N and He/H abundances are not included in the fit; they are used as an independent post-hoc test. That is a reasonable procedure, but the test fails for the donor: the predicted and observed C/N values are irreconcilable within the grid and the adopted parameters. The paper should either explicitly acknowledge that the abundance test is not reproduced, or refit the evolution including C/N (and He/H) in the χ2 to demonstrate that any part of the parameter space can simultaneously match all constraints.
minor comments (3)
  1. [Sections 5 and 6] The notation [C/N] is used inconsistently. In the text and figures, values such as [C/N]d = 0.39 and observed C/N = 2.14 are both referred to as 'C/N ratio (by mass fraction)', but the bracket notation usually denotes a logarithmic abundance ratio relative to a standard. Please define the notation explicitly and use it consistently; otherwise the numbers can be misread as dex values.
  2. [Figure 10 caption] The caption states 'current observed state of the Z Vul secondary (M2≈2.48 M⊙ at log t≈7)', while Table 2 gives M2=2.44±0.03 M⊙. Please harmonize the value used for the observed donor mass.
  3. [Section 5] Two consecutive paragraphs discuss thermohaline mixing and the gainer C/N prediction with nearly identical wording ('This process occurs when nucleosynthetically altered material...' and 'The calculated surface yields without thermohaline mixing...'). The duplication should be removed and the discussion consolidated.

Circularity Check

0 steps flagged

No significant circularity: the near-conservative beta is chi2-fitted to observed M, R, Teff; the C/N ratio is used as an independent (though discrepant) check, and the self-citations are methodological and corroborated by an independent AM-loss prescription.

full rationale

The central claim that Z Vul underwent a nearly conservative Case A mass transfer is derived from a chi-squared fit of a STARS evolutionary grid to the observed masses, radii, and effective temperatures (Eq. 5), with initial mass ratio and mass-transfer efficiency as free parameters. The C/N abundance ratio is not used in this fit; it is presented as an independent test. Equations (2)-(4) for the initial total mass and period are algebraic consequences of the definitions of beta and of the chosen specific angular-momentum-loss modes, not self-referential reductions. The paper does rely on its own previous formalism (Dervisoglu et al. 2018) for one AM-loss prescription, but the same conclusion is reproduced with the independent AM2 prescription from de Mink et al. (2007), so the self-citation is not load-bearing. The discrepancy between the grid-predicted donor C/N (~0.39) and the observed value (~2.14) is addressed by an ad hoc hypothesis in Section 6 that 0.2 solar masses less stripping would match the observation. This is a post-hoc adjustment and a correctness/robustness concern rather than a circular step, because the observed abundances were not used to define or select the best-fitting model. No step in the derivation reduces by construction to its own inputs or to an unverified self-citation chain.

Axiom & Free-Parameter Ledger

6 free parameters · 6 axioms · 1 invented entities

The central inference rests on the grid fit of qi and beta to the measured absolute parameters, plus a set of spectral and modeling assumptions about the faint secondary and the STARS CNO profiles. The ad hoc 0.2 Msun stripping offset is the most fragile ingredient.

free parameters (6)
  • mass transfer efficiency beta = 0.07±0.06 (AM1), 0.04±0.04 (AM2)
    Grid free parameter in qi-beta space; best-fit value is near conservative.
  • initial mass ratio qi = 1.37±0.07 (AM1), 1.41±0.10 (AM2)
    Grid free parameter; best-fit progenitor mass ratio.
  • spot parameters (8 values) = e.g., fT,p=0.85±0.05, fT,s=0.86±0.05; spot radii about 30 and 65 degrees
    MCMC fit to light curves to mimic localized circumstellar obscuration; adopted solution enters absolute parameters.
  • light-fraction linear coefficients lf_pa, lf_pb, lf_sa, lf_sb = Table 3, Run 4
    Fitted in iSpecMCMC renormalization of disentangled spectra; directly affects derived abundances.
  • atmospheric parameters of both components = Teff1=16760 K, Teff2=9690 K; logg1=3.88, logg2=3.45; [M/H]=0.00; vsini 111/95 km/s
    Fitted via MCMC to disentangled spectra; these enter the abundance analysis and absolute parameter set.
  • ad hoc stripping-depth offset = 0.2 Msun
    Introduced in Section 6 to reconcile predicted donor C/N (0.39) with observed C/N (2.14); not fitted, not present in the surviving grid, and inconsistent with the measured donor mass.
axioms (6)
  • standard math Orbital AM-loss formulas (Eqs. 2-4) from Giuricin & Mardirossian (1981) and Bhattacharya & van den Heuvel (1991) correctly describe non-conservative mass transfer.
    Used to map (qi, beta) to initial masses and periods; treated as established in the binary evolution literature.
  • domain assumption Fast and Isotropic Re-emission AM-loss modes bracket the unobserved rapid mass-transfer phase.
    The rapid mass-transfer phase is not observed; the authors explicitly rely on these a priori prescriptions.
  • domain assumption STARS code's CNO abundance profile, semiconvection, and diffusion at the exposed layers are accurate enough for 0.2 Msun-level strip-depth comparisons.
    Central to reconciling the donor C/N mismatch; no independent verification is provided.
  • domain assumption The fainter secondary's LTE abundance analysis yields a C/N ratio unaffected by renormalization and systematic errors.
    The authors note absolute secondary abundances are the most susceptible to systematics; they rely on ratio cancellation.
  • domain assumption Z Vul's initial composition is represented by the Nieva & Przybilla (2012) cosmic abundance standard.
    Used as the baseline for C/N and to rule out supersolar initial metallicity.
  • standard math Spectral line profiles do not vary except by dilution during out-of-eclipse phases.
    Required by the spectral disentangling method; the authors exclude eclipse spectra where the assumption is violated.
invented entities (1)
  • cool photospheric spots on both components no independent evidence
    purpose: Pragmatic stand-in for localized flux deficits from the intervening accretion structure; not actual magnetic spots.
    No magnetic activity is expected in these stars; the spots are an ad hoc parametrization, cross-checked only against another model with attenuation regions.

reviewed 2026-08-05 · how reviews work

0 comments
Cite this review

Pith. "Pith review of Unravelling Mass Transfer in Algols from Surface Abundances. I. Z Vulpeculae." pith.science (2026). https://pith.science/paper/LRUWK4HQ

@misc{pith2026260803348,
  author       = {Pith},
  title        = {Pith review of: Unravelling Mass Transfer in Algols from Surface Abundances. I. Z Vulpeculae},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/LRUWK4HQ}},
  note         = {Machine review of arXiv:2608.03348}
}
Share X Bluesky LinkedIn Reddit HN
read the original abstract

The photospheric abundance pattern of the components is a sensitive probe of mass and angular momentum transfer in Algols. With the aim to trace the evolutionary history and disclosed efficiency of mass transfer in Algols we collected new high-resolution spectra for about a dozen Algols with the {\sc hermes} spectrograph at the Mercator Telescope on La Palma, Canary Islands. In the present paper, which is the first in the series, we present the results of a comprehensive analysis of Z Vul, a hot Algol-type system. We derived the absolute stellar quantities and elemental abundances for the components. The carbon-to-nitrogen (C/N) ratio is the most sensitive tracer of thermonuclear processing and mass transfer. It is found to be within expected value for gainer but donor lacks the severe C/N inversion traditionally expected for a deeply stripped star. An extensive grid of over three million evolutionary models was calculated with the Cambridge \texttt{STARS} code which allows determination of the best-fitting and all surviving models. Constraints from the He and CNO abundances indicate that Z Vul underwent an episode of nearly conservative mass transfer during the Main Sequence life-time of the originally more massive component (Case A). Our detailed chemical tagging confirms that the surface abundances of the mass-losing component represent the delicately stripped outer layers still not reaching the CNO-rich core. This underscores the need of coupling high-resolution spectroscopic abundances with interior stellar profiles to accurately reconstruct the evolutionary history of interacting binaries.

Figures

Figures reproduced from arXiv: 2608.03348 by Ahmet Dervi\c{s}o\u{g}lu, Bar{\i}\c{s} Hoyman, David Mkrtichian, Ferhat G\"uney, Kresimir Pavlovski, \"Om\"ur \c{C}ak{\i}rl{\i}, Patricia Lampens, Peter De Cat, Simge Adalal{\i}, Timur \c{S}ahin.

Figure 1
Figure 1. Figure 1: Observed multi-wavelength light curves of Z Vul represented by blue and red symbols for the respective datasets, overlaid with the best-fit synthetic models (solid lines), along with the corresponding solution residuals (O − C) displayed in the bottom panels. The data suite used in the modeling consists of ground-based optical Johnson UBV photoelectric measurements from Broglia (1964), ground-based near-in… view at source ↗
Figure 3
Figure 3. Figure 3: Fractional light contribution of the primary component in Z Vul derived from the multi-wavelength light curve analysis. The entire ensemble of data points (combined red and black symbols) represents the full suite of photometric light curves modelled in this study, which includes Johnson UBV (Broglia 1964), TESS (four sectors), and Johnson NIR JHK (Lazaro et al. 2009). Black symbols specifically denote the… view at source ↗
Figure 4
Figure 4. Figure 4: Comparison of the best-fitting model and the renormalised observed disentangled spectra of the primary (left) and secondary (right) components, centred around Balmer lines Hα, Hβ and Hγ. The residuals are shown in the bottom panel. the yellow circles. Fixing the surface gravity of the components lifts the degeneracy with Teff present in hot stars. Run 3: in addition to the constraints on log g, the fractio… view at source ↗
Figure 5
Figure 5. Figure 5: Chemical abundance patterns of the Z Vul system. The primary and secondary components are shown with blue and red squares, respectively. Error bars indicate the derived uncertainties. Grey bands mark the present-day cosmic abundance standard of Nieva & Przybilla (2012). minations of the effective temperature of the primary component are within 2 − σ of the effective temperatures calculated in this study. I… view at source ↗
Figure 6
Figure 6. Figure 6: χ 2 topology maps within the initial mass ratio versus mass-transfer efficiency (q i–β) parameter space for the evolutionary grid of Z Vul. The left panel displays the Fast Case (AM1), and the right panel illustrates the Isotropic Re-emission Case (AM2). In both panels, the global χ 2 minimum (best-fit model) and the statistical confidence intervals (e.g., 1σ) utilized to isolate the surviving progenitor m… view at source ↗
Figure 7
Figure 7. Figure 7: Evolutionary diagnostic diagrams for Z Vul: the Kiel diagram (log g vs. log Teff; left panel) and the mass–radius diagram (right panel). In both panels, solid lines represent the best-fitting models, while dashed lines denote the surviving models within the confidence limits. The color-coding uniformly distinguishes the stellar components across the two AM loss regimes: blue and red lines represent the gai… view at source ↗
Figure 8
Figure 8. Figure 8: Expected surface carbon-to-nitrogen (C/N) ratio (by mass fraction) as a function of evolutionary path for the mass donor (left panel) and mass gainer (right panel) components of Z Vul, modeled under the Fast Case (AM1) scenario without the effects of thermohaline mixing. The tracks illustrate the depletion of the donor’s surface abundance as MT strips away the outer envelope, exposing deep, CNO-processed l… view at source ↗
Figure 9
Figure 9. Figure 9: Expected surface helium-to-hydrogen (He/H) ratio (by mass fraction) as a function of evolutionary path for the mass donor (left panel) and mass gainer (right panel) components of Z Vul, modeled without the effects of thermohaline mixing. The envelope stripping does not penetrate deeply into the advanced H-burning zones where extensive helium enrichment occurs. The right panel reflects the corresponding che… view at source ↗
Figure 10
Figure 10. Figure 10: ), the mass-loss process has stripped the secondary down only to the boundary where the C/N ratio begins to deviate from the solar value. It has not reached the deeply processed stellar core. This is definitively corroborated by the He/H profile, which shows the expected surface He/H ratio of the donor to be 0.408, exactly matching the 0.28/0.70 mass fraction ratio of unprocessed solar sur￾face material. … 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

210 extracted references · 49 canonical work pages · 17 internal anchors

  1. [1]

    Helium enrichment in O-type stars as a tracer of past binary interaction

    The IACOB project: XIII. Helium enrichment in O-type stars as a tracer of past binary interaction. , keywords =. doi:10.1051/0004-6361/202452622 , archivePrefix =. 2412.14107 , primaryClass =

  2. [2]

    Nitrogen abundances in Galactic O-type stars: further hints for separating binary-interaction products from effectively single stars

    The IACOB project: XVII. Nitrogen abundances in Galactic O-type stars: further hints for separating binary-interaction products from effectively single stars. arXiv e-prints , keywords =. doi:10.48550/arXiv.2604.26606 , archivePrefix =. 2604.26606 , primaryClass =

  3. [3]

    Surface helium abundances in Galactic O-type stars: indications for identifying binary interaction products

    The IACOB project: XVI. Surface helium abundances in Galactic O-type stars: indications for identifying binary interaction products. arXiv e-prints , keywords =. doi:10.48550/arXiv.2601.20698 , archivePrefix =. 2601.20698 , primaryClass =

  4. [4]

    5-m Kazan University Telescope at the Turkish National Observatory

    High-Resolution Coud \'e -Echelle Spectrometer for the 1. 5-m Kazan University Telescope at the Turkish National Observatory. The Carbon Star Phenomenon , year = 2000, editor =

  5. [5]

    Spin-orbit alignment for the circumbinary planet host EBLM J0608-59 A/TOI-1338 A

    The EBLM project - VII. Spin-orbit alignment for the circumbinary planet host EBLM J0608-59 A/TOI-1338 A. , keywords =. doi:10.1093/mnras/staa2071 , archivePrefix =. 2007.05514 , primaryClass =

  6. [6]

    , keywords =

    The Rossiter-McLaughlin effect reloaded: Probing the 3D spin-orbit geometry, differential stellar rotation, and the spatially-resolved stellar spectrum of star-planet systems. , keywords =. doi:10.1051/0004-6361/201527794 , archivePrefix =. 1602.00322 , primaryClass =

  7. [7]

    arXiv e-prints , keywords =

    Stable mass transfer in massive binaries leading to merging black holes. arXiv e-prints , keywords =. doi:10.48550/arXiv.2512.20054 , archivePrefix =. 2512.20054 , primaryClass =

  8. [8]

    , keywords =

    Comfort zones of stars: A limit on orbital tightening via stable mass transfer shapes the properties of binary black hole mergers. , keywords =. doi:10.1051/0004-6361/202555500 , archivePrefix =. 2505.08860 , primaryClass =

  9. [9]

    Non-conservative Mass Transfer as a Formation Channel for Gaia Black Hole System

    Non-conservative Mass Transfer as a Formation Channel for Gaia Black Hole System. arXiv e-prints , keywords =. doi:10.48550/arXiv.2511.10728 , archivePrefix =. 2511.10728 , primaryClass =

  10. [10]

    , keywords =

    Interacting Binaries on the Main Sequence as In Situ Tracers of Mass-transfer Efficiency and Stability. , keywords =. doi:10.3847/1538-4357/ae40fc , archivePrefix =. 2511.15347 , primaryClass =

  11. [11]

    , keywords =

    Detailed models of interacting short-period massive binary stars. , keywords =. doi:10.1051/0004-6361/202142574 , archivePrefix =. 2111.03329 , primaryClass =

  12. [12]

    , keywords =

    Spectral Disentangling Reveals Deep CNO-cycle Exposure in ET Cru. , keywords =. doi:10.3847/1538-3881/ae6cfb , archivePrefix =. 2605.14018 , primaryClass =

  13. [13]

    , keywords =

    Some aspects of mass loss and mass transfer in Algol variables. , keywords =. doi:10.1086/190732 , adsurl =

  14. [14]

    , year = 1955, month = jan, volume =

    On the Subgiant Components of Eclipsing Binary Systems. , year = 1955, month = jan, volume =

  15. [15]

    Annales d'Astrophysique , year = 1948, month = jan, volume =

    The masses and mass-ratios of close binary systems. Annales d'Astrophysique , year = 1948, month = jan, volume =

  16. [16]

    Beta Lyrae-nucleosynthesis revealed

    The chemical compositions of algol systems - III. Beta Lyrae-nucleosynthesis revealed. , keywords =. doi:10.1093/mnras/219.3.479 , adsurl =

  17. [17]

    , keywords =

    High signal-to-noise ratio The spectroscopic key to Algol systems. , keywords =. doi:10.1007/BF00215934 , adsurl =

  18. [18]

    Confirmation of carbon deficiencies in the primaries of eight systems

    The chemical compositions of Algol systems - V. Confirmation of carbon deficiencies in the primaries of eight systems. , keywords =. doi:10.1093/mnras/265.3.581 , adsurl =

  19. [19]

    The carbon and nitrogen abundances of the secondaries of U CEP and U Sge

    The chemical composition of Algol systems- II. The carbon and nitrogen abundances of the secondaries of U CEP and U Sge. , keywords =. doi:10.1093/mnras/203.4.1063 , adsurl =

  20. [20]

    , keywords =

    Energy distribution in the strongly interacting binary system SX Cas. , keywords =. doi:10.1086/159897 , adsurl =

  21. [21]

    , keywords =

    Far-ultraviolet emission lines in U Cephei : evidence for a hot, turbulent circumstellar envelope. , keywords =. doi:10.1086/161530 , adsurl =

  22. [22]

    , keywords =

    IUE and optical spectral scans of U Sagittae : an analysis and comparison with U Cephei. , keywords =. doi:10.1086/131509 , adsurl =

  23. [23]

    , keywords =

    Carbon abundance in beta Persei and lambda Tauri. , keywords =

  24. [24]

    , keywords =

    Carbon abundance in the primaries of six Algol-type stars. , keywords =

  25. [25]

    , year = 1996, month = mar, volume =

    Chemical Evolution of Algols. , year = 1996, month = mar, volume =

  26. [27]

    , keywords =

    Spin angular momentum evolution of the long-period Algols. , keywords =. doi:10.1111/j.1365-2966.2010.16732.x , archivePrefix =. 1003.4392 , primaryClass =

  27. [28]

    Tenth Pacific Rim Conference on Stellar Astrophysics , year = 2014, editor =

    Algol Evolution with Spin-down Mechanisms and Systemic Mass Loss. Tenth Pacific Rim Conference on Stellar Astrophysics , year = 2014, editor =

  28. [29]

    , keywords =

    Non-conservative evolution in Algols: where is the matter?. , keywords =. doi:10.1051/0004-6361/201424772 , archivePrefix =. 1502.04957 , primaryClass =

  29. [30]

    , keywords =

    The eclipsing binary V578 Mon in the Rosette nebula: age and distance to NGC 2244 using Fourier disentangled component spectra. , keywords =

  30. [31]

    , keywords =

    Abundances from disentangled component spectra: theeclipsing binary V578 Mon. , keywords =. doi:10.1051/0004-6361:20052804 , archivePrefix =. astro-ph/0504433 , primaryClass =

  31. [32]

    , keywords =

    Detection of the secondary of Algol. , keywords =. doi:10.1086/182705 , adsurl =

  32. [33]

    , keywords =

    Tracing CNO exposed layers in the Algol-type binary system u Her. , keywords =. doi:10.1093/mnras/stu1652 , archivePrefix =. 1408.2681 , primaryClass =

  33. [34]

    , keywords =

    Spectroscopically resolving the Algol triple system. , keywords =. doi:10.1093/mnras/stv1261 , archivePrefix =. 1506.01254 , primaryClass =

  34. [35]

    , keywords =

    Dynamical parallax, physical parameters, and evolutionary status of the components of the bright eclipsing binary Draconis. , keywords =. doi:10.1051/0004-6361/202142292 , archivePrefix =. 2111.03887 , primaryClass =

  35. [38]

    , keywords =

    Spectroscopic Modeling of the Algol-type Star TW Draconis. , keywords =. doi:10.1088/0004-6256/139/4/1327 , adsurl =

  36. [39]

    Spectroscopic modeling of oscillating Algol-type stars. I. RZ Cassiopeia. , keywords =. doi:10.1051/0004-6361/200911949 , adsurl =

  37. [40]

    , keywords =

    TX UMa: new orbit, spin rotation and chemical composition of components. , keywords =. doi:10.1111/j.1365-2966.2011.18854.x , adsurl =

  38. [41]

    , keywords =

    Properties of six short-period massive binaries: A study of the effects of binarity on surface chemical abundances. , keywords =. doi:10.1051/0004-6361/201731593 , archivePrefix =. 1709.00937 , primaryClass =

  39. [42]

    , keywords =

    A Catalog of Visual Double and Multiple Stars With Eclipsing Components. , keywords =. doi:10.1088/0004-6256/138/2/664 , archivePrefix =. 0907.5172 , primaryClass =

  40. [43]

    Publications of the Dominion Astrophysical Observatory Victoria , year = 1920, month = jan, volume =

    The spectroscopic orbit and dimensions of ZET Vul. Publications of the Dominion Astrophysical Observatory Victoria , year = 1920, month = jan, volume =

  41. [44]

    Rediscussion of Eclipsing Binaries. III. Z Vulpeculae. , year = 1957, month = jul, volume =. doi:10.1086/146371 , adsurl =

  42. [45]

    Journal des Observateurs , year = 1964, month = jan, volume =

    Observations photo \'e lectriques de la variable \`a \'e clipse Z Vulpeculae. Journal des Observateurs , year = 1964, month = jan, volume =

  43. [46]

    , keywords =

    Revised photometric elements of 12 semi-detached systems. , keywords =

  44. [47]

    Information Bulletin on Variable Stars , year = 1972, month = may, volume =

    Photoelectric Observations of the Eclipsing Variable Z Vulpeculae. Information Bulletin on Variable Stars , year = 1972, month = may, volume =

  45. [48]

    , year = 1975, month = jan, volume =

    Rotational velocities and spectral types for a sample of binary systems. , year = 1975, month = jan, volume =

  46. [49]

    , keywords =

    A search for rotational velocity changes among eclipsing binary stars. , keywords =. doi:10.1086/131349 , adsurl =

  47. [50]

    , keywords =

    On the linear polarization of close binaries. , keywords =. doi:10.1086/130092 , adsurl =

  48. [51]

    , keywords =

    Reanalysis of two eclipsing binaries: EE Aqr and Z Vul. , keywords =. doi:10.1007/s10509-008-9774-y , archivePrefix =. 0805.0489 , primaryClass =

  49. [52]

    , keywords =

    On OB-type close binary stars. , keywords =. doi:10.1093/mnras/229.4.529 , adsurl =

  50. [53]

    , keywords =

    Variations of the orbital periods in semi-detached binary stars with radiative outer layers. , keywords =. doi:10.1051/aas:1999122 , adsurl =

  51. [54]

    , keywords =

    Absolute parameters of the Algol binary Z Vul. , keywords =. doi:10.1016/j.newast.2009.01.010 , adsurl =

  52. [55]

    , keywords =

    A comparison between observed Algol-type double stars in the solar neighborhood and evolutionary computations of galactic case A binaries with a B-type primary at birth. , keywords =. doi:10.1051/0004-6361/201630131 , archivePrefix =. 1611.08398 , primaryClass =

  53. [56]

    , keywords =

    Magnetic braking at work in binaries. , keywords =. doi:10.1051/0004-6361/202038026 , archivePrefix =. 2003.11387 , primaryClass =

  54. [57]

    , keywords =

    Semidetached double-lined eclipsing binaries: Stellar parameters and rare classes. , keywords =. doi:10.1093/mnras/stz3363 , adsurl =

  55. [58]

    , keywords =

    Disentangling of composite spectra. , keywords =

  56. [59]

    , keywords =

    Orbital elements of multiple spectroscopic stars. , keywords =

  57. [60]

    From Interacting Binaries to Exoplanets: Essential Modeling Tools , year = 2012, editor =

    The Disentangling of Stellar Spectra. From Interacting Binaries to Exoplanets: Essential Modeling Tools , year = 2012, editor =. doi:10.1017/S1743921311027827 , adsurl =

  58. [61]

    , keywords =

    Determining stellar atmospheric parameters and chemical abundances of FGK stars with iSpec. , keywords =. doi:10.1051/0004-6361/201423945 , archivePrefix =. 1407.2608 , primaryClass =

  59. [62]

    , keywords =

    Modern stellar spectroscopy caveats. , keywords =. doi:10.1093/mnras/stz549 , archivePrefix =. 1902.09558 , primaryClass =

  60. [63]

    , keywords =

    emcee: The MCMC Hammer. , keywords =. doi:10.1086/670067 , archivePrefix =. 1202.3665 , primaryClass =

  61. [64]

    American Astronomical Society Meeting Abstracts \#215 , year = 2010, series =

    Kepler Planet Detection Mission: Introduction and First Results. American Astronomical Society Meeting Abstracts \#215 , year = 2010, series =

  62. [65]

    American Astronomical Society Meeting Abstracts \#224 , year = 2014, series =

    The Transiting Exoplanet Survey Satellite Mission. American Astronomical Society Meeting Abstracts \#224 , year = 2014, series =

  63. [66]

    Astrometric and photometric star catalogues derived from the ESA HIPPARCOS Space Astrometry Mission

    The HIPPARCOS and TYCHO catalogues. Astrometric and photometric star catalogues derived from the ESA HIPPARCOS Space Astrometry Mission. ESA Special Publication , year = 1997, editor =

  64. [67]

    Journal of Space Science Informatics Japan , volume=

    Automated wide-field survey for transient objects with a small telescope , author=. Journal of Space Science Informatics Japan , volume=

  65. [68]

    American Astronomical Society Meeting Abstracts \#223 , year = 2014, series =

    All Sky Automated Survey for SuperNovae (ASAS-SN or ``Assassin''). American Astronomical Society Meeting Abstracts \#223 , year = 2014, series =

  66. [69]

    , keywords =

    The All-Sky Automated Survey for Supernovae (ASAS-SN) Light Curve Server v1.0. , keywords =. doi:10.1088/1538-3873/aa80d9 , archivePrefix =. 1706.07060 , primaryClass =

  67. [70]

    Lightkurve: Kepler and TESS time series analysis in Python

  68. [71]

    , keywords =

    PolarBase: A Database of High-Resolution Spectropolarimetric Stellar Observations. , keywords =. doi:10.1086/676976 , archivePrefix =. 1401.1082 , primaryClass =

  69. [72]

    , keywords =

    Spectropolarimetric observations of active stars. , keywords =. doi:10.1093/mnras/291.4.658 , adsurl =

  70. [73]

    , year = 1971, month = jun, volume =

    Realization of Accurate Close-Binary Light Curves: Application to MR Cygni. , year = 1971, month = jun, volume =. doi:10.1086/150986 , adsurl =

  71. [74]

    , keywords =

    Unification of Binary Star Ephemeris Solutions. , keywords =. doi:10.1088/0004-637X/780/2/151 , adsurl =

  72. [75]

    Contributions of the Astronomical Observatory Skalnate Pleso , keywords =

    PyWD2015 - A new GUI for the Wilson-Devinney code. Contributions of the Astronomical Observatory Skalnate Pleso , keywords =. doi:10.31577/caosp.2020.50.2.535 , adsurl =

  73. [76]

    IAU Commission on Close Binary Stars , year = 1993, month = jan, volume =

    The new Wilson reflection treatment and the nature of BF Aurigae. IAU Commission on Close Binary Stars , year = 1993, month = jan, volume =

  74. [77]

    Evidence for conservative mass transfer in the classical Algol system $\delta$ Librae from its surface carbon-to-nitrogen abundance ratio

    Evidence for conservative mass transfer in the classical Algol system Librae from its surface carbon-to-nitrogen abundance ratio. , keywords =. doi:10.1093/mnras/sty2684 , archivePrefix =. 1810.01465 , primaryClass =

  75. [78]

    Spectroscopic long-term monitoring of RZ Cas. I. Basic stellar and system parameters. , keywords =. doi:10.1051/0004-6361/202039355 , archivePrefix =. 2011.07903 , primaryClass =

  76. [79]

    , keywords =

    A Possible Explanation of the O'Connell Effect in Close Binary Stars. , keywords =. doi:10.1088/1009-9271/3/2/142 , adsurl =

  77. [80]

    , keywords =

    V455 Car: An oscillating eclipsing Algol-type binary in triple star system. , keywords =. doi:10.1016/j.newast.2025.102412 , archivePrefix =. 2506.10124 , primaryClass =

  78. [81]

    , keywords =

    Mass and p-factor of the Type II Cepheid OGLE-LMC-T2CEP-098 in a Binary System. , keywords =. doi:10.3847/1538-4357/aa6ff7 , archivePrefix =. 1704.07782 , primaryClass =

  79. [82]

    Modern Analysis Techniques for Spectroscopic Binaries

    Modern Analysis Techniques for Spectroscopic Binaries. Binary Stars as Critical Tools & Tests in Contemporary Astrophysics , year = 2007, editor =. doi:10.1017/S1743921307003948 , archivePrefix =. astro-ph/0611422 , primaryClass =

  80. [83]

    Spectroscopically and Spatially Resolving the Components of the Close Binary Stars , year = 2004, editor =

    Obtaining normalised component spectra with FDBinary. Spectroscopically and Spatially Resolving the Components of the Close Binary Stars , year = 2004, editor =

Showing first 80 references.

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