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First mid-infrared detection and modeling of a flare from Sgr A*

T0 review · 4 major / 5 minor · reviewed 2026-08-10 · deepseek-v4-flash

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Pith's one-line read This paper reports the first mid-infrared detection of Sgr A* during a ~40-minute flare, and argues that the flare's reddening spectral index is synchrotron cooling in a 40–70 Gauss magnetic field.

desk verdict First MIR detection of Sgr A* is a real, carefully vetted observational result; the 40–70 G field estimate is model-dependent, and the paper mostly acknowledges that, but the framing should be softened. read the letter →

arxiv 2501.07415 v1 pith:FEMHEGAZ submitted 2025-01-13 astro-ph.HE astro-ph.GA

Sebastiano D. von Fellenberg , Tamojeet Roychowdhury , Joseph M. Michail , Zach Sumners , Grace Sanger-Johnson , Giovanni G. Fazio , Daryl Haggard , Joseph L. Hora
show 19 more authors
Alexander Philippov Bart Ripperda Howard A. Smith S. P. Willner Gunther Witzel Shuo Zhang Eric E. Becklin Geoffrey C. Bower Sunil Chandra Tuan Do Macarena Garcia Marin Mark A. Gurwell Nicole M. Ford Kazuhiro Hada Sera Markoff Mark R. Morris Joey Neilsen Nadeen B. Sabha Braden Seefeldt-Gail
This is my paper · ORCID
classification astro-ph.HEastro-ph.GA
keywords SgrA*mid-infraredsynchrotroncoolingmagneticfieldstrengthblackholeflareJWSTMIRIspectralindexGalacticCenter
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

This paper reports the first mid-infrared detection of Sgr A*, the Milky Way's central black hole, catching a flare that lasted roughly 40 minutes in all four bands of JWST's MIRI spectrometer. The authors find that the flare's spectral index stayed flat during the rise and then reddened by $\Delta\alpha \approx -0.4$ as the flare decayed, the first significant spectral-index change measured during a bright Sgr A* flare. They argue that this reddening is the signature of synchrotron cooling of a single population of injected electrons, and the implied cooling timescale requires a magnetic field of roughly 40–70 Gauss in the emission zone. A 1.3 mm flare seen by the SMA lagging by about 10 minutes is consistent with the cooled electrons radiating at lower frequencies. These results fill the long-missing mid-infrared window on Sgr A* variability and tie it to the non-thermal processes already invoked for NIR and X-ray flares.

What carries the argument

The central object is a one-zone synchrotron-cooling flare model: electrons are injected with a power-law energy distribution $dN/d\gamma \propto \gamma^{-p}$ in a constant magnetic field $B$, and the distribution evolves by the continuity equation $\partial N_e(\gamma,t)/\partial t = Q_{\rm inj} - \partial(\dot{\gamma} N_e)/\partial \gamma$ with no particle escape term (Equation C5). The load-bearing identity is the synchrotron cooling timescale $t_{\rm sync}(B,\nu) \approx 8\,(B/30\,{\rm G})^{-3/2}(\nu/10^{14}\,{\rm Hz})^{-1/2}$ minutes (Equation 1), which converts the observed ~5-minute decay and spectral reddening into a field strength of 40–70 G. The model also folds in Doppler boosting from a circular orbit and gravitational redshift, which together explain the flare's non-monotonic light curve; the numerical calculations are done with the flaremodel code.

What would settle it

Observe a future MIR flare of Sgr A* with simultaneous X-ray and 1.3 mm coverage. If the MIR flare decays without a reddening of $\Delta\alpha \approx -0.4$, or if no mm rise occurs within ~15 minutes of the MIR peak, the single-zone synchrotron-cooling model would be contradicted. A MIR flare accompanied by an X-ray flare would also violate the model's fixed high-energy cutoff and require a different injection spectrum.

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Extended reading notes

Core claim

The central discovery is that Sgr A*'s mid-infrared emission is not a passive tail of the quiescent accretion flow: it flares, and the flare's color evolution fingerprints the physics. In the 2024 April 6 JWST MIRI observation, the flare rose achromatically for the first ~10 minutes, then reddened by $\Delta\alpha \approx -0.4 \pm 0.1$ during a falling-and-rising phase, and finally decayed rapidly. The authors reproduce the light curves and color evolution with a model of a power-law electron population injected into a constant magnetic field and cooling by synchrotron emission while the emitting blob orbits the black hole, with Doppler boosting modulating the observed flux. The best-fit magnetic field strength is $B \approx 44^{+5}_{-6}$ G for the fiducial model, ranging up to ~62 G when a second injection event is added, and the model also produces a ~0.3 Jy increase at 1.3 mm that matches the SMA data. The conclusion is that MIR flares are synchrotron emission from cooling high-energy electrons, accelerated by magnetic reconnection and/or magnetized turbulence, and that non-thermal cooling must be included when modeling Sgr A*'s radio-to-mm emission.

Load-bearing premise

The reddening is attributed entirely to synchrotron cooling of electrons injected with a fixed power-law index $p=2$ into a constant magnetic field; if the injection spectrum evolves during the flare, or the magnetic field varies, the derived cooling timescale and the 40–70 Gauss field strength would not follow.

Editorial extensions

If this is right

  • MIR flares are a genuine part of Sgr A*'s flaring phenomenology, with durations comparable to NIR and X-ray flares, so any complete flare model must simultaneously match radio-to-X-ray light curves.
  • The measured reddening of $\Delta\alpha \approx -0.4$ during a bright flare is the first direct spectral evidence that synchrotron cooling operates on ~10-minute timescales in Sgr A*'s accretion flow.
  • The magnetic field in the flaring region is ~40–70 G, higher than the ~30 G often assumed but still within the range allowed by EHT-based modeling of the 2017 emission.
  • The ~10-minute lag and ~0.3 Jy rise at 1.3 mm are plausibly the cooled electron population, implying a physical connection between the MIR flare and the constantly varying mm emission.
  • Non-thermal electron cooling should be included in models of Sgr A*'s lower-energy radio emission, not only in the high-energy flare bands.

Reading between the lines

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

  • If the single-zone cooling picture is right, the same electrons should produce linearly polarized MIR emission whose position angle swings as the hotspot orbits; MIR polarimetry on a future flare could test the orbital and Doppler geometry directly.
  • The model's prediction that no X-rays accompany the MIR flare hinges on fixing $\gamma_{\max} \approx 3\times10^4$; a future simultaneous MIR and X-ray flare would measure the injection cutoff and could distinguish cooling from spectral evolution of the injection.
  • The authors fix the injection index at $p=2$; if future flares show reddening amplitudes that vary from event to event, the injection spectrum itself must vary, and the simple cooling-only interpretation would need to be extended.
  • The inferred electron magnetization $\sigma_e \gtrsim 10$ supports acceleration by magnetic reconnection or turbulence in magnetized cavities; compiling a sample of MIR flares could test how often such cavities form and whether their properties match GRMHD simulations.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 5 minor

Summary. The paper reports the first mid-infrared detection of Sgr A*, obtained with JWST/MIRI on 2024 April 6, during a flare lasting roughly 40–50 minutes and seen in four MRS bands at 5.3, 8.1, 12.5, and 19.3 μm. The authors measure a spectral-index reddening of Δα ≈ −0.4 ± 0.1 during the flare and present concurrent SMA 220 GHz and X-ray (Chandra and NuSTAR) observations, with no X-ray flare detected. They interpret the MIR flare as synchrotron emission from a single population of injected power-law electrons that cool during the flare, fit the light curves with a one-zone orbiting-blob model, and infer a magnetic field strength of roughly 40–70 G. The paper also estimates electron and proton magnetizations under assumptions about the emission-region size and compares the inferred field with EHT-based estimates. The observational detection appears robust, but the magnetic-field inference is strongly model-dependent and the mm association is treated as a prediction when the mm data were included in the fit.

Significance. If the detection and the spectral reddening hold up, this is a valuable new observational window: it fills the long-standing gap between NIR and mm flare observations of Sgr A* and provides a direct, time-resolved constraint on the flare spectrum in a regime that is sensitive to synchrotron cooling. The paper includes several good practices that deserve credit: a false-alarm analysis based on 190,000 bootstrapped spectral-index measurements, an independent 2D detector extraction that reproduces the cube-based light curves, a quantified normalization-uncertainty check, and publicly released modeling code (https://github.com/ydallilar/flaremodel). The central scientific claim, however, goes beyond the detection: converting the observed reddening into a 40–70 G field requires that the injected electron spectrum is a fixed power law with p = 2 and that no other mechanism (e.g., a time-varying injection index or magnetic field) produces the same spectral evolution. The paper itself acknowledges parts of this limitation in Appendix C.3, and the strength of the final claim should be tempered accordingly.

major comments (4)
  1. [Section 4.1 and Appendix C] The text describes the mm flux as 'a strong prediction of the model,' but the fit likelihood in Appendix C explicitly includes χ² from the SMA 220 GHz light curve, and B and log(ne) are fitted parameters. The mm light curve is therefore a consistency check with fitted quantities, not an independent prediction. The manuscript should either refit without the SMA data and then test the mm prediction, or rephrase this as a posterior consistency check rather than a prediction.
  2. [Appendix C, Eq. C5 and Section C.2] The inference B ≈ 40–70 G rests on the assumption that the injected electron spectrum is a fixed power law with p = 2 and that the magnetic field is constant, so that all spectral reddening is attributed to synchrotron cooling. The paper explicitly states that the data normalization leaves p unconstrained (Section C.2) and that a different injection treatment may alter the values (Section C.3). For optically thin synchrotron emission, a softening of the injection index from p ≈ 2 to p ≈ 2.8 would produce Δα ≈ −0.4 without any cooling. The authors should demonstrate that their field-strength conclusion is robust to time-dependent injection-spectrum evolution or variable B, or clearly present B as conditional on those assumptions.
  3. [Section C.2.1 and Section 4.2] The model fit has reduced χ² = 3.5 before per-channel error rescaling, and the rescaling factors reach 3.47 for channel 1. In addition, Section 4.2 states that error bars for two data points in channels 1 and 2 were inflated by a factor of 3 to avoid biasing the fit by the double-peak feature. This means the formal posterior widths from the MCMC fit likely underestimate the true model uncertainty. The paper should provide a more transparent discussion of model inadequacy and, where possible, quote parameter uncertainties that include the lack-of-fit contribution.
  4. [Table C1 and Section C.2.1] There is an internal inconsistency in the reported fit quality for the p = 3 case. The text says 'The difference in χ² is negligible (Δχ² = 0.1, see Table C1),' but Table C1 lists χ²_red = 1.2 for the p = 3 row, which is very different from the best-fit χ²_red = 3.5. The authors need to clarify whether the numbers refer to different data sets, different error rescaling, or a typographical error.
minor comments (5)
  1. [Section 4.1 and Abstract] The abstract says the flare lasted about 40 minutes, while Section 4.1 says the flare lasted about 50 minutes; please make these consistent.
  2. [Section 2.1] The sentence 'Since our signal is significant at <4σ, the FAR<190,000⁻¹' is not a standard way to quote a false-alarm rate. Please explain more explicitly how the 190,000 bootstrap samples translate into the quoted false-alarm probability.
  3. [Figures and text] There are several typographical issues: 'GRA VITY' appears with a visible space throughout, the Dodds-Eden et al. 2010 reference is duplicated, 'fondes de Recherche' should be 'Fonds de Recherche', and some table headers are broken across lines (e.g., 'T able A1').
  4. [Figure 4] In Figure 4, the plotted data points appear to lack visible error bars, even though uncertainties are used in the fit; please ensure that error bars are shown and legible.
  5. [Table C1] The column layout of Table C1 is confusing: the 'p' and 'R_flare' columns are not clearly separated, and some rows (e.g., the second 'Best Fit' row with '≡ 1.0') are hard to interpret. Please reformat so each free parameter has its own labeled column.

Circularity Check

1 steps flagged · score 6.0 of 10

The MIR detection and the spectral-index reddening are observed and not circular, but the paper's 'strong prediction' of the millimeter flare is a fitted input: the SMA 220 GHz light curve was included in the model's chi-squared, so reproducing it is a consistency check rather than an independent prediction.

  1. fitted input called prediction [Section 4.1 (Flare Modeling) and Appendix C (Flare Modeling), fitting text before Table C1.]
    "A strong prediction of the model is that as the electrons cool to lower energies, they must emit synchrotron radiation at lower frequencies. If γmin = 10 and the total electron number density in the emitting region ne ≈ 1–10 × 10^6 cm^-3, the model produces mm flux in the range of the observed values while at the same time fitting the observed MIR flare (Figure 4). ... The model was fit using the MCMC code emcee ... using a χ2 likelihood that included χ2 from all four MIRI channels and from the SMA light curve."

    The SMA 220 GHz light curve is one of the data sets entering the model's χ2; the parameters that set the mm flux (B, ne, γmin, and the constant 220 GHz offset o) were adjusted against that same light curve. The model's reproduction of the mm rise is therefore a restatement of the fit, not a prediction that could have failed independently. This is the fitted-input-called-prediction pattern: the 'strong prediction' is the fitted data described as an output.

full rationale

The primary detection claim and the measured spectral reddening (Δα ≈ -0.4, false-alarm rate < 1/190000, including a 2D-detector cross-check in Appendix A) are observational and do not reduce to the model's inputs. The conversion of the reddening into a synchrotron-cooling timescale and B ≈ 40–70 G does depend on the model assumptions: a fixed injected power-law index p = 2, a constant B, and a single cooling population (Appendix C, Eqs. C2–C5). The paper itself notes that the flux normalization leaves p unconstrained and cautions that a different injection treatment may alter the values (Sections C.2 and C.3), so that dependence is a modeling limitation or correctness risk, not a circularity. The one clear circular step is the mm 'prediction': because the SMA light curve was included in the χ2 likelihood used to fit B and ne, the model's mm output is a fitted quantity, not an independent prediction. The core MIR result and the B-field inference from the MIR spectral-index evolution retain independent content, so the circularity is partial rather than total.

Assumptions & free parameters 13 free parameters · 7 assumptions · 0 invented entities

The detection is observational and stands largely on the data reduction, but the magnetic field and mm-flux inferences rest on a one-zone synchrotron model with multiple fitted or hand-set parameters, a fixed injection spectrum, and a normalization that assumes extinction is static. The mm flux is not an independent prediction because the SMA data were included in the same fit.

free parameters (13)
  • Magnetic field strength B = 44 +5/-6 G (best fit; 38-62 G across model variants)
    Fitted to MIR and SMA light curves; drives the cooling timescale and the central magnetic field estimate.
  • Electron number density log10(ne) = 6.9 +0.3/-0.2 cm^-3
    Fitted to absolute flux normalization; the modeled mm flux depends strongly on this value.
  • Gaussian injection width sigma = 16.7 +1.3/-1.3 minutes
    Fitted to the flare rise and decay shape.
  • Injection peak time tmax = 20.9 +2.1/-2.4 minutes
    Fitted to the light-curve timing.
  • Orbital phase Omega0 = 221 +9/-9 degrees
    Fitted to the Doppler modulation pattern.
  • Orbital radius R_orb/R_S = 6.2 +0.1/-0.1 R_S
    Fitted to the Doppler modulation amplitude; the magnetization estimate instead uses a flat prior on Rflare in [0.8, 2.3] R_S.
  • Orbital inclination phi = 17 to 25 degrees depending on fit
    Fitted or fixed across model variants; controls the Doppler boosting magnitude.
  • Electron power-law index p = 2 (fixed; p=3 explored)
    Chosen by hand to match the canonical NIR spectral slope; the MIR flux normalization leaves it poorly constrained.
  • Minimum Lorentz factor gamma_min = 10
    Set to the typical thermal electron energy; the predicted mm flux depends on this choice.
  • Maximum Lorentz factor gamma_max = 3e4
    Set to avoid producing X-ray emission, consistent with the absence of an X-ray flare.
  • mm constant offset o = 0.04 Jy
    Added to represent synchrotron emission from low-energy thermal electrons; fitted.
  • Per-channel error rescaling factors f = fCH1=3.47, fCH2=1.35, fCH3=0.75, fCH4=0.7, f220=1.3
    Applied after fitting to force reduced chi2=1, acknowledging unmodeled variability.
  • Error inflation factor for two data points = 3.0
    Errors at t=25.5 and 28.5 minutes in channels 1 and 2 were inflated to avoid biasing the fit by an unexplained double-peak.
assumptions (7)
  • standard math Standard synchrotron emissivity and cooling formulas (Blumenthal and Gould 1970; Eq. 1).
    Used to compute the light curves and to translate the observed spectral evolution into a magnetic field strength.
  • domain assumption Single-zone spherical emission region with constant magnetic field, constant radius, and no particle escape or expansion.
    Simplification in Appendix C; if the region expands or particles escape, the B and density estimates shift.
  • domain assumption Injected electron distribution is a power law dN/dE proportional to gamma^-p with fixed p, gamma_min, and gamma_max.
    Eqs. C3-C4; p=2 is chosen to match NIR observations and is not constrained by the MIR data.
  • domain assumption Doppler boosting from a circular orbit plus gravitational redshift, with lensing and higher-order GR ignored, valid for inclination below about 50 degrees.
    Eqs. C7-C8; the orbital parameters are weakly constrained and affect the shape of the modeled light curve.
  • domain assumption Normalization of the light curves (Eq. A1) removes static extinction and background, and the MIRI systematics (fringing, PSF undersampling) are constant over the flare.
    Appendix A; if the extinction or static flux changed during the flare, the measured spectral-index change would be biased.
  • domain assumption The accretion flow is in a magnetically arrested state and flares arise from orbiting magnetic flux tubes, as argued from cited GRMHD and EHT work.
    Motivates the model and the magnetization interpretation, though it is not required for the detection itself.
  • domain assumption Flat prior on the emission-region radius Rflare in [0.8, 2.3] R_S, motivated by GRMHD simulation flux-tube sizes.
    Section C.2.1; the derived magnetization posterior depends on this prior.

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Pith. "Pith review of First mid-infrared detection and modeling of a flare from Sgr A*." pith.science (2026). https://pith.science/paper/FEMHEGAZ

@misc{pith2026250107415,
  author       = {Pith},
  title        = {Pith review of: First mid-infrared detection and modeling of a flare from Sgr A*},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/FEMHEGAZ}},
  note         = {Machine review of arXiv:2501.07415}
}
abstract

The time-variable emission from the accretion flow of Sgr A*, the supermassive black hole at the Galactic Center, has long been examined in the radio-to-mm, near-infrared (NIR), and X-ray regimes of the electromagnetic spectrum. However, until now, sensitivity and angular resolution have been insufficient in the crucial mid-infrared (MIR) regime. The MIRI instrument on JWST has changed that, and we report the first MIR detection of Sgr A*. The detection was during a flare that lasted about 40 minutes, a duration similar to NIR and X-ray flares, and the source's spectral index steepened as the flare ended. The steepening suggests synchrotron cooling is an important process for Sgr A*'s variability and implies magnetic field strengths $\sim$40--70 Gauss in the emission zone. Observations at $1.3~\mathrm{mm}$ with the Submillimeter Array revealed a counterpart flare lagging the MIR flare by $\approx$10 minutes. The observations can be self-consistently explained as synchrotron radiation from a single population of gradually cooling high-energy electrons accelerated through (a combination of) magnetic reconnection and/or magnetized turbulence.

Figures

Figures reproduced from arXiv: 2501.07415 by the authors.

Figure 1
Figure 1. Mid infrared images of the Galactic Center with JWST. The color insets show JWST 5.3 µm (A), 8.1 µm (B), 12.5 µm (C), and 19.3 µm (D) observations. The JWST/MIRI images are superposed on the L ′ (NIR 3.8 µm) stellar-background image from the Keck Observatory (Hora et al. 2014). The image scale is labeled in arcseconds with Sgr A* at the origin. North is up, east to the left. The data show characteristics of the know… view at source ↗
Figure 2
Figure 2. Images and light curves of Sgr A* observed on 2024-04-06. [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗
Figure 3
Figure 3. Full multi-wavelength Sgr A* light curves on 2024 April 6. [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗
Figures from the paper (1 more)
Figure 4
Figure 4. Figure 4: Observed light curves with model fit. Points show the observed data, and solid lines show the predictions of the simple model described in the text. (A) 220 GHz data. (B) MIR data. The four yellow-to-red lines show the best-fit model predictions for each channel as lab…

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Reference graph

Works this paper leans on

12 extracted references · 11 canonical work pages · cited by 1 Pith paper

  1. [1]

    K., Bautz, M

    Baganoff, F. K., Bautz, M. W., Brandt, W. N., et al. 2001, Nature, 413, 45, doi: 10.1038/35092510 Ball, D., ¨Ozel, F., Psaltis, D., & Chan, C.-k. 2016, Astrophysical Journal, 826, 77, doi: 10.3847/0004-637X/826/1/77 Bisnovatyi-Kogan, G. S., & Ruzmaikin, A. A. 1974, Ap&SS, 28, 45 —. 1976, Ap&SS, 42, 401 Blumenthal, G. R., & Gould, R. J. 1970, Reviews of Mo...

    arXiv doi:10.48550/arxiv.2409.11486 2001

  2. [4]

    Axis labels are in pixel number with pixel angular sizes given in the text

    The location of Sgr A* is marked with the square box, and the locations of the reference pixels used to estimate the noise in the image are marked by white dots. Axis labels are in pixel number with pixel angular sizes given in the text. The flux-density scale is in MJy/sr. To extract Sgr A*’s flux density, we created median-subtracted data cubes. In the ...

    work page 2024

  3. [6]

    (C5) 16 No particle escape term (Blumenthal & Gould 1970; Dodds-Eden et al

    The electron energy distribution as a function of time is given by the continuity equation ∂Ne(γ, t) ∂t = Qinj − ∂( ˙γNe) ∂γ . (C5) 16 No particle escape term (Blumenthal & Gould 1970; Dodds-Eden et al

    work page 1970

  4. [7]

    2023; Lemoine

    is included in the model as motivated by the long confinement timescale (Kempski et al. 2023; Lemoine

    work page 2023

  5. [8]

    longitude

    τconf ∝ rg c rg rLarmor 1/3 (C6) and absence of substantial outflows from the flux tube region as motivated by GRMHD simulations (Ripperda et al. 2022). We solved Equation C5 numerically and computed the resulting synchrotron emission from the emission region for each time step using the code flaremodel (Dallilar et al. 2022). Once the intrinsic emission ...

    work page 2022

  6. [10]

    This corresponds to the typically quoted energy of the ambient thermal electrons responsible for the bulk of the mm emission (e.g., von Fellenberg et al. 2018). The Chandra X-ray observations constrain γmax: depending on γmax and the power-law slope p, the model could produce significant synchrotron flux at X-ray energies. The absence of the X-ray emissio...

    work page 2018

  7. [20]

    In the absence of astrometric or polarimetric measurements of the flare, the orbital parameters of the flare are poorly constrained

    The difference in χ2 is negligible (∆χ2 = 0.1, see Table C1). In the absence of astrometric or polarimetric measurements of the flare, the orbital parameters of the flare are poorly constrained. In particular, the inclination, which causes stronger or weaker magnification, is largely degenerate with the strength of the intrinsic emission. For the fit repo...

    work page 2022

  8. [104]

    We therefore set p = 2, which gives the canonically observed NIR spectral slope Fν,NIR ∝ ν−0.5 (e.g., Hornstein et al

    Similarly, the normalization of the flux density leaves p unconstrained. We therefore set p = 2, which gives the canonically observed NIR spectral slope Fν,NIR ∝ ν−0.5 (e.g., Hornstein et al. 2007). C.2.1. Single Injection Event Table C1 reports the model’s posterior parameters. The best-fit model has a reduced χ2 = 3.5. Because the light curve shows smal...

    work page 2007

Show all 12 references
  1. [2011]

    Haubois et al

    is applied. Haubois et al. (2012) obtained MIR observation during a bright NIR flare and obtained a 3 σ flux limit of 5 .1 mJy, or 22 .4 mJy if extinction correction is applied. The last work, Dinh et al. (2024), focuses on compact objects and temperature maps of the central r...

    2012

  2. [2013]

    We used a standard setup of 32 “walkers” and started the sampling chain at a region visually perceived as a good fit

    using a χ2 likelihood that included χ2 from all four MIRI channels and from the SMA light curve. We used a standard setup of 32 “walkers” and started the sampling chain at a region visually perceived as a good fit. The chain ran for 1000 steps, but we discarded the first 500 s...

    2011

  3. [2023]

    2023; Lemoine 2023)

    that can trap accelerated electrons (Kempski et al. 2023; Lemoine 2023). The general idea of particle energization due to turbulence and reconnection in a magnetized and orbiting cavity motivated us to model the flare spectrum as arising from a spherical, orbiting, one-zone em...

    2023

  4. [2024]

    2020, 2023)

    and simulations of the wind- fed accretion onto the Galactic center (Ressler et al. 2020, 2023). In this scenario, a large amount of magnetic flux is accreted onto the black hole with the infalling gas. The flux on the horizon can then become strong enough to repel the accreti...

    2020

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