Evolution of Accretion Disk Structure of the Black Hole X-ray Binary MAXI J1820$+$070 during the Rebrightening Phase

Daisaku Nogami; Hiroyuki Maehara; Hitoshi Negoro; Ichiro Takahashi; Katsuhiro L. Murata; Keisuke Isogai; Mahito Sasada; Masafumi Niwano; Masaki Takayama; Megumi Shidatsu

REVIEW 4 major objections 5 minor 70 references

Evolution of Accretion Disk Structure of the Black Hole X-ray Binary MAXI J1820$+$070 during the Rebrightening Phase

T0 review · 4 major / 5 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 During the 2019 rebrightening of the black hole X-ray binary MAXI J1820+070, the optical/UV light was dominated by jet synchrotron radiation, and Balmer line profiles show the irradiated disk's inner edge moved inward from about 200,000…

desk verdict A careful multi-wavelength SED and optical spectroscopy study of MAXI J1820's rebrightening; the jet-dominated optical/UV interpretation is well supported, but the claimed Balmer-line inner-radius decrease rests on line widths near the instrumental resolution and should be treated as fragile. read the letter →

arxiv 2412.11445 v1 pith:GAGQ34K3 submitted 2024-12-16 astro-ph.HE

Tomohiro Yoshitake , Megumi Shidatsu , Yoshihiro Ueda , Daisaku Nogami , Katsuhiro L. Murata , Narikazu Higuchi , Keisuke Isogai , Hiroyuki Maehara

show 13 more authors

Shin Mineshige Hitoshi Negoro Nobuyuki Kawai Yoichi Yatsu Mahito Sasada Ichiro Takahashi Masafumi Niwano Tomoki Saito Masaki Takayama Yumiko Oasa Takuya Takarada Takumi Shigeyoshi OISTER Collaboration

This is my paper · ORCID

classification astro-ph.HE

keywords blackholeX-raybinaryMAXIJ1820+070rebrighteningaccretiondiskjetsynchrotronemissionlow/hardstateBalmerlineprofilesADAF

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

The paper tracks the black hole X-ray binary MAXI J1820+070 through its 2019–2020 rebrightenings, when the system stayed in the low/hard state at very low Eddington ratios. By assembling near-infrared, optical, UV, and X-ray spectral energy distributions at seven epochs, it argues that in the rising and decaying phases (Periods I and II) the optical/UV continuum was dominated not by an irradiated accretion disk but by synchrotron radiation from a jet, with a single power law smoothly connecting to same-day radio flux. The optical spectra show broad Balmer absorption with narrower emission, and fitting these with Keplerian disk profiles indicates the inner radius of the irradiated disk shrank from roughly $2\times10^5$ gravitational radii in Period I to about $1\times10^5$ in Period II, implying the hot-corona geometry changed. In the final dim phase (Period III), the SED is reproduced by an advection-dominated accretion flow plus jet emission, while double-peaked H$\alpha$ shows a cool disk persisted at large radii. If correct, the picture maps how the inner disk, corona, and jet rearrange as the accretion rate falls.

What carries the argument

The central machinery is the multi-band spectral decomposition: a broken power law with a high-energy cutoff standing in for the jet's optically thick-to-thin synchrotron spectrum, an irradiated multi-color disk model for the outer disk, a power law for coronal X-rays, and a blackbody for the companion star, with an ADAF-based cutoff-plus-power-law combination used in the dim phase. On the line side, a disk-line model that computes Keplerian Doppler profiles from an illuminated disk, plus a negative Gaussian for the broad absorption, converts measured line widths into radii through the Keplerian relation $R_{\rm in} \propto (HWZI/\lambda_{\rm rest})^{-2}$, assuming an inclination. This lets the authors translate a spectral shape and line widths into a physical geometry: a truncated standard disk, a hot inner flow, a jet, and an irradiated outer disk whose inner edge changes between periods.

What would settle it

A clear P Cygni profile or a blueshifted absorption component at velocities above roughly 1000 km/s in a higher-signal-to-noise spectrum taken in Period I or II would indicate a wind and break the Keplerian interpretation. Conversely, finding that the optical power law does not connect to simultaneous radio flux in additional epochs, or detecting a spectral break within the observed optical/UV band, would weaken the jet-synchrotron assignment.

Watch

Extended reading notes

Core claim

The paper's central discovery is that the rebrightening phase of MAXI J1820+070 is not a scaled-down version of the main outburst: in the low/hard state at Eddington ratios below about $10^{-3}$, the optical/near-infrared/UV continuum is traced by a power law best explained as jet synchrotron emission, with the irradiated disk contributing at most a partial component, while the X-rays come from a hot corona via Comptonization. The authors show the power-law index is consistent with an optically thick conical jet and that the extrapolated spectrum lands on simultaneous radio data. From the width of broad Balmer absorption assumed to arise in the disk, they derive that the inner radius of the irradiated, line-forming part of the disk decreased from $\sim 2\times10^5 r_{\rm g}$ in the rising period to $\sim 1\times10^5 r_{\rm g}$ in the decay period, which they interpret as an inward extension of the irradiated region and a change in hot-corona geometry during the rebrightening. In the dim phase the hot inner flow is replaced by an advection-dominated accretion flow, yet a cool disk remains beyond about $10^5 r_{\rm g}$.

Load-bearing premise

The derived disk radii rest on the assumption that the broad Balmer absorption and emission lines form in a Keplerian accretion disk rather than in a disk wind; the paper states this explicitly in Section 4.2, and a significant wind would invalidate the line-width-to-radius conversion. The absolute radii also depend on the adopted distance, black hole mass, and inclination.

Editorial extensions

If this is right

In low/hard-state rebrightenings, optical/UV SEDs fitted without a jet component will attribute jet flux to the irradiated disk and therefore misestimate disk radii and irradiation efficiencies.
The disk truncation radius appears to grow as the X-ray luminosity falls in the low/hard state, reaching roughly $2.5\times10^2 r_{\rm g}$ at the rebrightening peak and larger radii at lower flux.
The inner edge of the irradiated, line-forming disk moves inward from about $2\times10^5$ to about $1\times10^5 r_{\rm g}$ as the rebrightening decays, tying line-profile variability to corona geometry.
In the dim phase, the absence of broad absorption and the presence of a double-peaked H$\alpha$ line indicate that the hot-mode disk has disappeared while a cool disk survives at radii beyond about $10^5 r_{\rm g}$.

Reading between the lines

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

A natural next test: apply the same jet-plus-disk decomposition to other black hole X-ray binaries in rebrightening, predicting that optical/UV jet dominance should appear whenever the Eddington ratio is below roughly $10^{-3}$ and the X-ray spectrum is hard; simultaneous radio and optical monitoring would confirm or break this pattern.
The inferred inward motion of the irradiated disk edge may reflect a geometric response of the inner hot flow rather than a true change in the disk truncation radius; a direct test would be measuring the X-ray reflection or iron-line radius at the same epochs.
Because the rebrightening light curves of MAXI J1820+070 are similar across events, comparing Balmer line profiles at the same phase over multiple rebrightenings would show whether the disk geometry is reproducible.
A higher-resolution spectrum searching for P Cygni profiles or time-dependent absorption would settle whether any part of the broad Balmer absorption is wind-formed; as the paper notes, the current data cannot rule out weak high-velocity winds.

Share X Bluesky LinkedIn Reddit HN

Signed reviews

No signed human review yet.

Editorial analysis

A structured set of objections, weighed in public.

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

Desk Editor's Note

read the letter

Quick take: this is the first systematic SED analysis of an entire rebrightening phase of MAXI J1820, dividing it into three periods and arguing that the near-IR/optical/UV emission in the first two periods is jet-dominated synchrotron. That argument is reasonably well supported: the power-law slope is consistent with an optically thick jet, the one same-day VLA radio point connects smoothly to the extrapolated optical/UV component, and the Ljet-LX correlation is coherent. The diskir-versus-jet model comparison on Epoch (c) is fair, and the Period III ADAF result is a confirmation of Yoshitake et al. (2022), properly cited. The paper is honest about its caveats, which matters here because the main fragility is disclosed rather than hidden. The soft spot is Conclusion 2, the claimed decrease of the inner irradiated-disk radius from ~2e5 to ~1e5 gravitational radii. The reader's report flags the disk-wind assumption, and the authors do too. But the sharper problem is resolution. The two H-beta emission spectra were taken with different KOOLS-IFU response FWHMs, 12.61 A in Period I and 7.35 A in Period II. The intrinsic HWZI values are 11 A and 14 A, which after convolution give nearly identical observed widths. The Period I line is at or below the resolution limit, so the deconvolved width and the resulting inner radius are not secure. A modest uncertainty in the Gaussian response can erase the 3 A difference, and no systematic error from the response width is propagated into Rin. The mapping of 2020 spectra onto 2019 periods by g-band phase further weakens the temporal interpretation. So the inner-radius evolution should be downgraded to speculative. The rest of the paper, including the jet dominance and the three-period classification, does not depend on it. The data handling and fitting look solid: NH is fixed from a consistent X-ray fit, fit statistics are reported, and parameter uncertainties are quoted. The citation pattern is fine; the self-citation is for a previously published result being confirmed. Who should read this: people working on low-luminosity BHXB outbursts, jet-disk coupling, and irradiated disk modeling. It deserves serious peer review, but the referee should require the authors to quantify the spectral-response systematics on the Balmer line widths and either weaken Conclusion 2 or support it with independent data. I would send it out.

Referee Report

4 major / 5 minor

Summary. The paper analyzes multi-wavelength SEDs (near-IR/optical/UV from OISTER/LCO/Swift and X-rays from Swift/NICER/NuSTAR) of the black hole X-ray binary MAXI J1820+070 during its 2019 rebrightening, together with Seimei optical spectra from 2019 and 2020. The rebrightening is divided into three periods on the basis of the optical and X-ray light curves and their flux ratio. The authors find that in Periods I and II the source stays in the low/hard state, with X-ray spectra approximated by power laws and the near-IR/optical/UV SED dominated by a power-law component that they interpret as jet synchrotron emission, supported by a single-epoch radio measurement. From Balmer line profiles they claim that the inner radius of the irradiated disk decreased from roughly 2e5 gravitational radii in Period I to roughly 1e5 gravitational radii in Period II. In Period III the SED is reproduced by an ADAF plus jet model, while the double-peaked Halpha line indicates a cool disk at large radii.

Significance. The paper compiles a valuable multi-wavelength data set for a rarely observed low-luminosity rebrightening phase and presents a coherent SED modeling effort. The jet-dominated optical/UV interpretation in Periods I and II is supported by an extrapolation to simultaneous radio data, and the Period III ADAF analysis is consistent with earlier work. The period classification based on the optical-to-X-ray flux ratio is a useful empirical framework. However, the headline claim of a factor-of-two decrease in the disk inner radius between Periods I and II rests on deconvolved line widths that are at or below the instrumental resolution, and the temporal mapping between the 2020 spectra and the 2019 periods introduces an additional assumption. These issues make the disk-evolution conclusion fragile, even though the SED results themselves are likely robust.

major comments (4)

[Section 3.3, Table 5; Section 4.2.1; Conclusion 2] The claimed decrease of the Hbeta emitting inner radius from ~2e5 r_g to ~1e5 r_g is not secured by the measured line widths once instrumental resolution is taken into account. On 2020 Feb 23 (Period I) the response FWHM is 12.61 A while the best-fit emission HWZI is 11 A; on 2020 Mar 18 (Period II) the response FWHM is 7.35 A and the HWZI is 14 A. The corresponding observed widths, sqrt(11^2 + 12.61^2) = 16.7 A and sqrt(14^2 + 7.35^2) = 15.8 A, are nearly identical, so the Period I line is effectively unresolved and the intrinsic HWZI depends on deconvolving a feature narrower than the line-spread function. The reported R_in values of 1.7e5 r_g (Period I) and 1.1e5 r_g (Period II) do not include any systematic uncertainty in the assumed Gaussian response width. Please re-fit using the measured line-spread function, propagate response-width systematics, or explicitly remove the radius-evolution claim unless it can be shown to survive these uncertainties.
[Section 4.2; Section 4.2.1] The Keplerian-radius interpretation in Section 4.2.1 relies on the assumption stated in Section 4.2 that 'the main absorption and line features are not produced by a disk wind.' The Halpha absorption in Period I is blueshifted by about 500 km/s, and the authors acknowledge that high-velocity disk winds cannot be ruled out with the available signal-to-noise ratio. Because the inferred inner radii and their evolution are the central result, this assumption is load-bearing. Please provide an explicit test of the disk-wind hypothesis (for example, time variability of the absorption profile, detailed profile asymmetry, or comparison with wind radiative-transfer models) or clearly present the radii as conditional on the no-wind assumption.
[Section 3.2, Figure 3, Table 3] The decomposition between the jet and the irradiated disk is partly determined by model assumptions in the unobserved UV-X-ray gap. The bknpower break and highecut cutoff are fixed by hand at 1e-2 keV and 3e-2 keV, and in Epoch (c) the diskir parameter fout pegs at its lower limit while the Wien peak of the multi-color disk is not covered. Consequently, the statement that the diskir contribution to the optical/UV flux is a factor of 5 smaller than the jet component is model-dependent. Please quantify this systematic uncertainty by re-fitting with the break and cutoff energies varied over a plausible range (for example 1e-3 to 1e-1 keV) and by profiling over the diskir parameters that are currently pegged or unconstrained.
[Section 3.3] The two Seimei spectra used to infer the Period I-to-II evolution were obtained during the 2020 rebrightening and are assigned to Periods I and II only by their phase relative to the g-band peak. The Period definitions in Section 3.1, however, are based on the 2019 X-ray and optical flux-ratio evolution. Without simultaneous X-ray or UV data from 2020, the mapping between the two rebrightenings is an additional assumption that is not tested in the paper. Please either verify this mapping with 2020 X-ray/optical data, or treat the line-radius comparison as tentative and explicitly discuss the systematic uncertainty introduced by the cross-rebrightening timing.

minor comments (5)

[Section 4.1.1] The energy-index sign convention is confusing: the text first gives photon indices Gamma = 1.1-1.4 (energy indices alpha = 0.1-0.48) and then refers to energy indices -0.4 <~ alpha <~ -0.3; please define alpha consistently as F_nu proportional to nu^{-alpha} and check the signs throughout.
[Table 5 and Equation (1)] The use of the 5-sigma width of a Gaussian component as the HWZI should be defined explicitly, and the relation between the quoted 1-sigma errors on HWZI and the assumed line profile should be stated so that readers can judge how the R_in uncertainties are derived.
[Figure 3] The three-panel caption is difficult to follow: the middle panel is described as the 'best-fit highecut*bknpower+diskir+bbodyrad model' and the right panel as 'same as the middle panel, but corrected for interstellar extinction,' while the left panel is the X-ray fit; please label the panels (a)-(c) explicitly in the caption and in the text.
[Section 2.5] There is a typo in the first sentence: 'rebrighening' should be 'rebrightening'.
[Table 3] The diskir parameter fout is reported as pegged at its lower limit; the text should explicitly note that this is a lower-limit measurement and that the diskir normalization and R_out are therefore not independently constrained by the data.

Circularity Check

0 steps flagged · score 2.0 of 10

No significant circularity: the SED and line-profile results are independent empirical fits, with only minor non-load-bearing self-citation and an unresolved-line robustness concern that is not a circularity.

full rationale

The paper's central claims rest on empirical SED fitting and line-profile modeling with standard external models (power-law, bknpower, diskir, ADAF approximations). The jet-synchrotron interpretation is supported by an independent radio data point from VLA that was not included in the fit; the optical/UV power law is extrapolated to radio and compared with that external measurement, which is a genuine prediction rather than a fitted input. The Balmer-line inner radii are free outputs of the diskline fits: the Hβ emission HWZI values of 11 Å and 14 Å are converted to Rin via the Keplerian relation, and the assumed outer radius of 2.4×10^5 rg does not determine the fitted inner radius, because the line wings are governed by the inner edge of the emitting region. No equation in the paper equates a fitted parameter with the claimed result by construction; no uniqueness theorem or ansatz is imported from the authors' prior work in a load-bearing way. The only self-citation is Yoshitake et al. (2022), used for the Period III interpretation and for adopting i=70° and emissivity index α=−3; these are parameter choices and a re-analysis of previously published data, not an unverified premise that forces the new conclusions. The skeptical concern that the Hβ intrinsic widths are at or below the Seimei spectral resolution and that the two epochs have different response FWHMs is a legitimate robustness/correctness issue about deconvolution, but it is not a circularity: the paper does not assume the radius decrease into the fit, and the resolution limitation does not make the derivation self-referential. Therefore the circularity score is low, reflecting only the minor self-citation and no load-bearing circular step.

Assumptions & free parameters 7 free parameters · 7 assumptions · 0 invented entities

The central claims rest on standard accretion and radiation models, fixed system parameters from previous measurements, and one explicit assumption about line origin (no disk wind). No new physical entities are postulated. The most fragile input is the line-origin assumption, which directly supports the inner radius evolution claim.

free parameters (7)

X-ray photon index Gamma = 1.1 to 2.1 across epochs
Fitted per epoch to the absorbed power-law X-ray spectrum; used to characterize the coronal emission.
Jet power-law photon index below break (Gamma_jet) = 0.7 to 1.4 across epochs
Fitted to the optical/UV power-law component in each epoch; central to the jet-dominance interpretation.
Jet break and cutoff energies = 1e-2 keV and 3e-2 keV
Fixed by hand because no data exist between UV and X-ray bands; affects the decomposition between jet and power-law components.
Outer irradiation fraction fout (diskir) = 1.0e-3 (pegged)
Allowed to vary in Epoch (c) within 1e-3 to 1e-2; pegged at lower bound, influencing the diskir contribution to optical/UV.
Inner disk temperature Tin (diskir) = 3.1e-2 keV
Fitted in Epoch (c); poorly constrained because the MCD peak is not covered by the data.
diskir normalization, log(Rout/Rin), Lc/Ld = 2.4e5 rg, 1.0e3, 9.9 (Epoch c)
Fitted parameters of the diskir model; the outer radius is later used as a fixed input to the line profile fitting.
ADAF peak energy and normalization (Period III) = Epeak 7.1e-4 keV, norm 4.8e4
Fitted to the optical-X-ray SED in Epoch (g) following Yoshitake et al. (2022).

assumptions (7)

domain assumption The irradiated disk model (diskir) describes the outer disk emission in the low/hard state.
Used in Sections 3.2 and 4.1 as a standard model for the accretion disk, but the fits find its contribution to optical/UV to be small.
domain assumption The optical/UV power-law component is synchrotron radiation from a jet with a broken power-law spectrum.
Invoked in Section 3.2 with the bknpower/highecut model; supported by the radio connection in one epoch.
domain assumption The accretion flow in Period III is an advection-dominated accretion flow (ADAF) with synchro-cyclotron emission.
Adopted from Yoshitake et al. (2022) and standard ADAF theory; used to reproduce the Epoch (g) SED.
domain assumption Balmer lines are formed in a Keplerian disk and their widths map to radii via the diskline model.
Central to Section 4.2; assumes no disk wind and uses emissivity index alpha = -3, i = 70 deg, outer radius 2.4e5 rg.
ad hoc to paper The absorption and emission line features are not produced by a disk wind.
Explicitly stated in Section 4.2; if false, the derived line radii and their evolution are invalid.
domain assumption Fixed system parameters: distance D = 3 kpc, black hole mass M = 7-8 Msun, inclination i = 69-77 deg, E(B-V) = 0.16, companion temperature and radius.
Taken from prior literature (Gandhi 2019, Torres 2019, Baglio 2018) and used in SED and line fitting throughout.
domain assumption The 2019 and 2020 rebrightenings have similar light-curve shapes, allowing combination of spectra from different years.
Used in Section 3.3 to assign 2020 spectra to Periods I and II based on days from peak, despite the spectra being from a different rebrightening event.

how reviews work

0 comments

Cite this review

Pith. "Pith review of Evolution of Accretion Disk Structure of the Black Hole X-ray Binary MAXI J1820$+$070 during the Rebrightening Phase." pith.science (2026). https://pith.science/paper/GAGQ34K3

@misc{pith2026241211445,
  author       = {Pith},
  title        = {Pith review of: Evolution of Accretion Disk Structure of the Black Hole X-ray Binary MAXI J1820$+$070 during the Rebrightening Phase},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/GAGQ34K3}},
  note         = {Machine review of arXiv:2412.11445}
}

abstract

To understand the evolution of global accretion disk structure in the ``rebrightening'' phase of MAXI J1820$+$070, we perform a comprehensive analysis of its near infrared/optical/UV to X-ray spectral energy distribution (SED) utilizing data obtained by OISTER, Las Cumbres Observatory (LCO), Swift, NICER, and NuSTAR in 2019. Optical spectra observed with Seimei telescope in 2019 and 2020 are also analyzed. On the basis of the optical and X-ray light curves and their flux ratios, we divide the whole phase into 3 periods, Periods I (flux rise), II (decay), and III (dim). In the first 2 periods, the source stayed in the low/hard state (LHS), where the X-ray (0.3--30 keV) and optical/UV SED can be both fitted with power-law models. We interpret that the X-ray emission arises from hot corona via Comptonization, whereas the optical/UV flux is dominated by synchrotron radiation from the jets, with a partial contribution from the irradiated disk. The optical/UV power-law component smoothly connects to a simultaneous radio flux, supporting its jet origin. Balmer line profiles in the optical spectra indicate that the inner radius of an irradiated disk slightly decreased from $\sim 2\times 10^5 r_{\rm g}$ (Period I) to $\sim 1\times 10^5 r_{\rm g}$ (Period II), where $r_{\rm g}$ is the gravitational radius, implying a change of the hot corona geometry. In Period III, the SED can be reproduced by an advection-dominated accretion flow and jet emission. However, the double-peaked H$\alpha$ emission line indicates that a cool disk remained at large radii.

Figures

Figures reproduced from arXiv: 2412.11445 by the authors.

**Figure 1.** (a) Optical (g’-band) light curve of MAXI J1820 from the OISTER collaboration (Higuchi et al. in preparation). MJD 58200 corresponds to 2018 March 23. (b) The g’-band light curves in the three rebrightening phases, in which the values on the horizontal axis are adjusted with the flux peaks (MJD 58567, 58721, and 58909 for the first, second, and third rebrightenings, respectively). The flux densities in the second … view at source ↗

**Figure 3.** (Left) X-ray spectrum in Epoch (c) and its best-fit absorbed power-law model. (Middle) multi-wavelength SEDs and best-fit highecut*bknpower+diskir+bbodyrad model in Epoch (c). The bottom panel shows the data versus model ratio. (Right) same as the middle panel, but corrected for interstellar extinction. Solid, dotted, dashed, and dot dashed lines show the total model and the diskir, highecut*bknpower, and bbodyrad c… view at source ↗

**Figure 4.** The multi-wavelength SEDs and best-fit models corrected for interstellar extinction. The Swift/XRT, Swift/UVOT, NuSTAR, NICER, OISTER, and LCO data are shown in blue circles, green triangles, purple diamonds, dark blue stars, red inverse triangles, and orange squares, respectively. The adopted models are highecut*bknpower+powerlaw+bbodyrad for Period I and II, and highecut*bknpower+cutoffpl+powerlaw+bbodyrad for Per… view at source ↗

Figures from the paper (6 more)

**Figure 5.** Figure 5: Seimei spectra obtained in the three epochs. The panels (a), (b), and (c) correspond to Period I, II, and III, respectively. The inset panels show enlarged views around Hα (λ = 6563 A), H ˚ β (λ = 4861 A), and He I ( ˚ λ = 5876 A) lines. Other identified lines are also…

**Figure 6.** Figure 6: Seimei/KOOLS-IFU spectra around the Hα and Hβ lines and their best-fit models. Gray solid and orange dashed lines present the total model and the sum of the continuum and absorption line components, respectively. Note that the data and the model include broadening due …

**Figure 7.** Figure 7: Optical-UV SED and the best-fit model in Epoch (f) (same as [PITH_FULL_IMAGE:figures/full_fig_p012_7.png]

**Figure 8.** Figure 8: Correlation of the unabsorbed X-ray luminosity and optical jet luminosity of MAXI J1820. The blue circles, red triangles, green squares, and yellow star show the data taken in Period I, II, and III, and in the LHS of the main outburst (Shidatsu et al. 2018), respectiv…

**Figure 8.** Figure 8: As noticed, it generally follows the relation ob [PITH_FULL_IMAGE:figures/full_fig_p014_8.png]

**Figure 9.** Figure 9: schematic picture of the accretion disk in the three periods. locity provides a model-independent estimate of the outer radius of the line-forming region. The half separation of the peaks is estimated to be 8.5±1.5 ˚A, which corresponds to (3 ± 1) × 105 rg for i = 70◦ …

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

70 extracted references · 37 canonical work pages

[1]

C., Russell, D

Baglio, M. C., Russell, D. M., & Lewis, F. 2018, The Astronomer’s Telegram, 11418, 1

2018
[2]

Barden, S. C., ed. 1995, Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol. 2476, Fiber Optics in Astronomical Applications, ed. S. C. Barden, 56–67

work page 1995
[3]

C., McKee, C

Begelman, M. C., McKee, C. F., & Shields, G. A. 1983, ApJ, 271, 70

1983
[4]

1996, A&AS, 117, 393

Bertin, E., & Arnouts, S. 1996, A&AS, 117, 393

1996
[5]

D., & K¨ onigl, A

Blandford, R. D., & K¨ onigl, A. 1979, ApJ, 232, 34

1979
[6]

Boffin, H. M. J. 2001, in Astrotomography, Indirect Imaging Methods in Observational Astronomy, ed. H. M. J. Boffin, D. Steeghs, & J. Cuypers, Vol. 573 (Springer), 69

work page 2001
[7]

N., Hill, J

Burrows, D. N., Hill, J. E., Nousek, J. A., et al. 2005, SSRv, 120, 165

work page 2005
[8]

C., Charles, P

Casares, J., Martin, A. C., Charles, P. A., et al. 1995, MNRAS, 276, L35

work page 1995

Show all 70 references

[9]

C., Magnier, E

Chambers, K. C., Magnier, E. A., Metcalfe, N., et al. 2016, arXiv e-prints, arXiv:1612.05560

2016 arXiv
[10]

2013, MNRAS, 428, 2500

Corbel, S., Coriat, M., Brocksopp, C., et al. 2013, MNRAS, 428, 2500

2013
[11]

Craine, D. L. C. E. R., ed. 1994, Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol. 2198, Instrumentation in Astronomy VIII, ed. D. L. C. E. R. Craine, 87–97 —. 2010, Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, V...

1994
[12]

M., Skrutskie, M

Cutri, R. M., Skrutskie, M. F., van Dyk, S., et al. 2003, 2MASS All Sky Catalog of point sources

2003
[13]

2007, A&A Rv, 15, 1

Done, C., Gierli´ nski, M., & Kubota, A. 2007, A&A Rv, 15, 1

2007
[14]

Dubus, G., Kim, R. S. J., Menou, K., Szkody, P., & Bowen, D. V. 2001, ApJ, 553, 307

2001
[15]

1993, ApJ, 403, 684 Publications of the Astronomical Society of Japan , (2018), Vol

Ebisawa, K., Makino, F., Mitsuda, K., et al. 1993, ApJ, 403, 684 Publications of the Astronomical Society of Japan , (2018), Vol. 00, No. 0 17 Echibur´ u-Trujillo, C., Tetarenko, A. J., Haggard, D., et al. 2023, arXiv e-prints, arXiv:2311.11523

2018 arXiv
[16]

C., Rees, M

Fabian, A. C., Rees, M. J., Stella, L., & White, N. E. 1989, MNRAS, 238, 729

1989
[17]

Maccarone, T. J. 2019, MNRAS, 485, 2642 Gierli´ nski, M., Done, C., & Page, K. 2008, MNRAS, 388, 753 —. 2009, MNRAS, 392, 1106

2019
[18]

2000, A&A, 353, 244 HI4PI Collaboration, Ben Bekhti, N., Fl¨ oer, L., et al

Hameury, J.-M., Lasota, J.-P., & Warner, B. 2000, A&A, 353, 244 HI4PI Collaboration, Ben Bekhti, N., Fl¨ oer, L., et al. 2016, A&A, 594, A116

2000
[19]

2009, PASJ, 61, 697

Hiroi, K., Moritani, Y., Nogami, D., et al. 2009, PASJ, 61, 697

2009
[20]

Horne, K., & Marsh, T. R. 1986, MNRAS, 218, 761

1986
[21]

Hynes, R. I. 2005, ApJ, 623, 1026

2005
[22]

2011, Annu

Kuroda, T. 2011, Annu. Rep. Nishi-Harima Astron. Obs., 21, 13

2011
[23]

A., Raymond, J

Jimenez-Garate, M. A., Raymond, J. C., & Liedahl, D. A. 2002, ApJ, 581, 1297 Jim´ enez-Ibarra, F., Mu˜ noz-Darias, T., Armas Padilla, M., et al. 2019, MNRAS, 484, 2078

2002
[24]

1998, in Astronomical Society of the Pacific Conference Series, Vol

Kato, T., Nogami, D., Baba, H., & Matsumoto, K. 1998, in Astronomical Society of the Pacific Conference Series, Vol. 137, Wild Stars in the Old West, ed. S. Howell, E. Kuulkers, & C. Woodward, 9

1998
[25]

2018, The Astronomer’s Telegram, 11399, 1

Kawamuro, T., Negoro, H., Yoneyama, T., et al. 2018, The Astronomer’s Telegram, 11399, 1

2018
[26]

Koljonen, K. I. I., Long, K. S., Matthews, J. H., & Knigge, C. 2023, MNRAS, 521, 4190

2023
[27]

2005, Nuovo Cimento C Geophysics Space Physics C, 28, 755

Kotani, T., Kawai, N., Yanagisawa, K., et al. 2005, Nuovo Cimento C Geophysics Space Physics C, 28, 755

2005
[28]

Kron, R. G. 1980, ApJS, 43, 305

1980
[29]

M., Lattanzi, M

Lasker, B. M., Lattanzi, M. G., McLean, B. J., et al. 2008, AJ, 136, 735

2008
[30]

2001, New Astronomy Reviews, 45, 449

Lasota, J.-P. 2001, New Astronomy Reviews, 45, 449

2001
[31]

Maccarone, T. J. 2003, A&A, 409, 697

2003
[32]

2008, PASJ, 60, 585

Makishima, K., Takahashi, H., Yamada, S., et al. 2008, PASJ, 60, 585

2008
[33]

1997, ApJ, 489, 791

Manmoto, T., Mineshige, S., & Kusunose, M. 1997, ApJ, 489, 791

1997
[34]

2019, PASJ, 71, 102

Matsubayashi, K., Ohta, K., Iwamuro, F., et al. 2019, PASJ, 71, 102

2019
[35]

2009, Publications of the Astronomical Society of Japan, 61, 999

Matsuoka, M., Kawasaki, K., Ueno, S., et al. 2009, Publications of the Astronomical Society of Japan, 61, 999

2009
[36]

2015, PASJ, 67, 52

Meyer, F., & Meyer-Hofmeister, E. 2015, PASJ, 67, 52

2015
[37]

Mineshige, S., & Wheeler, J. C. 1989, ApJ, 343, 241 Mu˜ noz-Darias, T., Casares, J., Mata S´ anchez, D., et al. 2016, Nature, 534, 75 —. 2017, MNRAS, 465, L124 Mu˜ noz-Darias, T., Jim´ enez-Ibarra, F., Panizo-Espinar, G., et al. 2019, ApJL, 879, L4

1989
[38]

1995, ApJ, 452, 710

Narayan, R., & Yi, I. 1995, ApJ, 452, 710

1995
[39]

2020, in Ground- based and Airborne Instrumentation for Astronomy VIII, Vol

Oasa, Y., Ushioda, K., Shibata, Y., et al. 2020, in Ground- based and Airborne Instrumentation for Astronomy VIII, Vol. 11447, International Society for Optics and Photonics, 114475Z

2020
[40]

2001, A&A, 370, 488 ¨Ozbey Arabacı, M., Kalemci, E., Din¸ cer, T., et al

Osaki, Y., Meyer, F., & Meyer-Hofmeister, E. 2001, A&A, 370, 488 ¨Ozbey Arabacı, M., Kalemci, E., Din¸ cer, T., et al. 2022, MNRAS, 514, 3894 Paczy´ nski, B. 1971, ARA&A, 9, 183

2001
[41]

2021, ApJ, 910, 21

Rodi, J., Tramacere, A., Onori, F., et al. 2021, ApJ, 910, 21

2021
[42]

M., Fender, R

Russell, D. M., Fender, R. P., Hynes, R. I., et al. 2006, MNRAS, 371, 1334

2006
[43]

M., Maitra, D., Dunn, R

Russell, D. M., Maitra, D., Dunn, R. J. H., & Markoff, S. 2010, MNRAS, 405, 1759

2010
[44]

2021, MNRAS, 504, 4226

Sai, H., Wang, X., Wu, J., et al. 2021, MNRAS, 504, 4226

2021
[45]

M., Pirbhoy, S

Saikia, P., Russell, D. M., Pirbhoy, S. F., et al. 2023, ApJ, 949, 104 S´ anchez-Sierras, J., & Mu˜ noz-Darias, T. 2020, A&A, 640, L3

2023
[46]

I., & Sunyaev, R

Shakura, N. I., & Sunyaev, R. A. 1973, A&A, 500, 33

1973
[47]

L., et al

Shidatsu, M., Nakahira, S., Murata, K. L., et al. 2019, ApJ, 874, 183

2019
[48]

2018, ApJ, 868, 54

Shidatsu, M., Nakahira, S., Yamada, S., et al. 2018, ApJ, 868, 54

2018
[49]

2008, in American Institute of Physics Conference Series, Vol

Shimokawabe, T., Kawai, N., Kotani, T., et al. 2008, in American Institute of Physics Conference Series, Vol. 1000, Gamma-ray Bursts 2007, ed. M. Galassi, D. Palmer, & E. Fenimore, 543–546

2008
[50]

Soria, R., Wu, K., & Hunstead, R. W. 2000, ApJ, 539, 445

2000
[51]

Stiele, H., & Kong, A. K. H. 2020, ApJ, 889, 142

2020
[52]

2013, Bull

Takahashi, J., Zenno, T., & Ishiguro, M. 2013, Bull. Cent. Astron. Univ. Hyogo, 1, 17–22

2013
[53]

1996, ARA&A, 34, 607

Tanaka, Y., & Shibazaki, N. 1996, ARA&A, 34, 607

1996
[54]

J., Casella, P., Miller-Jones, J

Tetarenko, A. J., Casella, P., Miller-Jones, J. C. A., et al. 2021, MNRAS, 504, 3862

2021
[55]

E., Shaw, A

Tetarenko, B. E., Shaw, A. W., & Charles, P. A. 2023, MNRAS, 526, 6284

2023
[56]

E., Sivakoff, G

Tetarenko, B. E., Sivakoff, G. R., Heinke, C. O., & Gladstone, J. C. 2016, ApJS, 222, 15

2016
[57]

A., Yamaoka, K., Corbel, S., et al

Tomsick, J. A., Yamaoka, K., Corbel, S., et al. 2009, ApJL, 707, L87

2009
[58]

Torres, M. A. P., Casares, J., Jim´ enez-Ibarra, F., et al. 2020, ApJL, 893, L37 —. 2019b, ApJL, 882, L21

2020
[59]

A., Shappee, B

Tucker, M. A., Shappee, B. J., Holoien, T. W. S., et al. 2018, ApJL, 867, L9

2018
[60]

1998, ApJ, 492, 782

Ueda, Y., Inoue, H., Tanaka, Y., et al. 1998, ApJ, 492, 782

1998
[61]

2018, The Astronomer’s Telegram, 11423, 1 Vahdat Motlagh, A., Kalemci, E., & Maccarone, T

Uttley, P., Gendreau, K., Markwardt, C., et al. 2018, The Astronomer’s Telegram, 11423, 1 Vahdat Motlagh, A., Kalemci, E., & Maccarone, T. J. 2019, MNRAS, 485, 2744 van Paradijs, J., & McClintock, J. E. 1994, A&A, 290, 133

2018
[62]

2000, ApJ, 542, 914

Wilms, J., Allen, A., & McCray, R. 2000, ApJ, 542, 914

2000
[63]

2013, PASJ, 65, 80

Yamada, S., Makishima, K., Done, C., et al. 2013, PASJ, 65, 80

2013
[64]

2010, in American Institute of Physics Conference Series, Vol

Yanagisawa, K., Kuroda, D., Yoshida, M., et al. 2010, in American Institute of Physics Conference Series, Vol. 1279, 18 Publications of the Astronomical Society of Japan , (2018), Vol. 00, No. 0 Deciphering the Ancient Universe with Gamma-ray Bursts, ed. N. Kawai & S. Nagataki...

2018
[65]

2015, MNRAS, 447, 1692

Yang, Q.-X., Xie, F.-G., Yuan, F., et al. 2015, MNRAS, 447, 1692

2015
[66]

2007, Physica E Low-Dimensional Systems and Nanostructures, 40, 434

Yatsu, Y., Kawai, N., Shimokawabe, T., et al. 2007, Physica E Low-Dimensional Systems and Nanostructures, 40, 434

2007
[67]

2005, Journal of Korean Astronomical Society, 38, 117

Yoshida, M. 2005, Journal of Korean Astronomical Society, 38, 117

2005
[68]

2022, PASJ, 74, 805

Yoshitake, T., Shidatsu, M., Ueda, Y., et al. 2022, PASJ, 74, 805

2022
[69]

B., Bernardini, F., Russell, D

Zhang, G. B., Bernardini, F., Russell, D. M., et al. 2019, ApJ, 876, 5

2019
[70]

2002, MNRAS, 334, 999

Zurita, C., S´ anchez-Fern´ andez, C., Casares, J., et al. 2002, MNRAS, 334, 999

2002

Pith tools

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

[1] [1]

C., Russell, D

Baglio, M. C., Russell, D. M., & Lewis, F. 2018, The Astronomer’s Telegram, 11418, 1

2018

[2] [2]

Barden, S. C., ed. 1995, Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol. 2476, Fiber Optics in Astronomical Applications, ed. S. C. Barden, 56–67

work page 1995

[3] [3]

C., McKee, C

Begelman, M. C., McKee, C. F., & Shields, G. A. 1983, ApJ, 271, 70

1983

[4] [4]

1996, A&AS, 117, 393

Bertin, E., & Arnouts, S. 1996, A&AS, 117, 393

1996

[5] [5]

D., & K¨ onigl, A

Blandford, R. D., & K¨ onigl, A. 1979, ApJ, 232, 34

1979

[6] [6]

Boffin, H. M. J. 2001, in Astrotomography, Indirect Imaging Methods in Observational Astronomy, ed. H. M. J. Boffin, D. Steeghs, & J. Cuypers, Vol. 573 (Springer), 69

work page 2001

[7] [7]

N., Hill, J

Burrows, D. N., Hill, J. E., Nousek, J. A., et al. 2005, SSRv, 120, 165

work page 2005

[8] [8]

C., Charles, P

Casares, J., Martin, A. C., Charles, P. A., et al. 1995, MNRAS, 276, L35

work page 1995