REVIEW 3 major objections 6 minor 86 references
Radio activity in changing-look AGNs tracks long-term accretion history and jet evolution, not the instantaneous look change.
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 →
T0 review · grok-4.5
2026-07-11 20:01 UTC pith:XGXP5WL7
load-bearing objection Solid survey paper: higher Pj/Lbol for radio CL-AGNs and four real radio transients (incl. turn-offs) are the keepers; the “long-term history not instantaneous CL” claim is over-sold on five kpc-scale tracks. the 3 major comments →
Radio Activity Across Accretion State Changes in Changing-look AGNs: Insights from FIRST and VLASS over Two Decades
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
From 1092 CL-AGNs the authors isolate 58 radio detections. These objects have systematically higher radio-kinetic efficiency Pj/Lbol than both typical radio AGNs and radio transients, matching their low-Eddington-ratio preference. At the population level the anti-correlation of radio strength with accretion rate is weak, yet a clear source-by-source anti-correlation appears in the few objects with continuous multi-epoch coverage. Four radio transients (turn-on and turn-off) and one multiwavelength flare candidate are identified as rare channels. The paper therefore claims that radio activity is regulated by long-term accretion history and jet evolution rather than by the instantaneous accret
What carries the argument
Radio-kinetic efficiency Pj/Lbol, obtained by converting FIRST/VLASS fluxes to rest-frame luminosity (with a fixed spectral index) via the Rusinek jet-power relation and dividing by bolometric luminosity from L5100. Tracked against quasi-simultaneous Eddington ratios over the ~20-year FIRST-to-VLASS baseline, and examined source-by-source on the radio-loudness versus Eddington-ratio plane, this ratio is the quantity that carries the claim that long-term history dominates over instantaneous state.
Load-bearing premise
The argument treats decade-scale, arcsecond-resolution radio fluxes—which mainly sample kiloparsec jets and lobes—as informative about how jets respond to the inner, parsec-scale accretion changes that drive changing-look transitions.
What would settle it
VLBI imaging of a well-monitored CL-AGN sample that shows compact parsec-scale cores systematically brightening or quenching within months of a documented optical state change, while the extended emission stays fixed, would demonstrate that radio activity does respond promptly to instantaneous accretion changes and would overturn the long-term-history claim.
If this is right
- Most CL-AGNs will not display dramatic radio switches concurrent with optical type changes when observed at arcsecond resolution.
- Coordinated high-resolution (VLBI) monitoring of pc-scale cores is required to test whether CL transitions launch or quench compact jets on the relevant scales.
- Higher jet production efficiency at low Eddington ratio extends the disk–jet coupling picture into the CL-AGN regime on long timescales.
- Rare radio turn-on and turn-off events among CL-AGNs remain usable laboratories for newly launched or dying compact jets.
- Future multi-epoch radio surveys can treat CL-AGNs as a pre-selected population in which both gradual jet evolution and stochastic transients can be caught.
Where Pith is reading between the lines
- Sparse spectroscopic sampling relative to radio epochs means many intervening CL episodes may be missed, so any true short-timescale radio response could still be under-counted.
- If delayed radio brightening after nuclear flares is common (as the single flare-like source hints), CL-AGN catalogs may hide a population of outflow-driven radio afterglows that FIRST/VLASS cadence cannot resolve.
- Adding simultaneous low-frequency LOFAR indices and VLBI core imaging would separate stable steep-spectrum lobes from inverted-spectrum young jets and quantify how often CL events actually birth compact jets.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper studies long-term radio properties of changing-look AGNs by cross-matching a parent sample of 1092 literature CL-AGNs with FIRST and VLASS, yielding 58 radio detections over ~20 years. It constructs control samples of radio-silent CL-AGNs, typical SDSS Type 1 AGNs, and literature radio transients, derives quasi-simultaneous L_5100 from ZTF photometry anchored to spectral decompositions, and measures radio-kinetic efficiency P_j/L_bol (Eqs. 4–5, 7). Radio-detected CL-AGNs show higher P_j/L_bol than controls and prefer low Eddington ratios near ~0.01. Population-level anti-correlation of radio strength with accretion rate is weak (Fig. 5), but five sources with multi-epoch FIRST/VLASS + optical coverage show source-by-source anti-correlation on the R–λ_Edd plane (Table 1, Fig. 7). Four radio transients (turn-on and turn-off) and one multiwavelength flare candidate are identified. The authors conclude that radio activity is regulated by long-term accretion history and jet evolution rather than instantaneous CL state changes, with rare stochastic/transient channels.
Significance. If the interpretation holds, the work supplies a useful population baseline for disk–jet coupling in CL-AGNs: a carefully purity-controlled radio detection rate, elevated kinetic efficiency relative to typical AGNs and radio transients, and the first report of both radio turn-on and turn-off events inside a CL-AGN sample. The multi-control design (radio-silent CL-AGNs, SDSS Type 1s, literature transients), explicit matching cuts, K-S tests, and transparent timelines (Figs. 10–11, Table A) are strengths that make the catalog and efficiency comparison reusable. The central evolutionary claim is more provisional because it rests on five multi-epoch tracks and arcsecond-scale fluxes, but the paper itself flags those limitations and does not oversell a causal CL–jet link. The result is a solid observational contribution that clarifies what FIRST/VLASS can and cannot say about CL–jet coupling.
major comments (3)
- §4.3.2, Table 1, Fig. 7, and Abstract/§5 points 2 and 5: The load-bearing claim that radio activity is not governed by instantaneous CL state changes but by long-term history rests primarily on five multi-epoch sources. Absolute radio fluxes are largely stable (Fig. 6; §4.5), so the reported anti-correlation is driven largely by changes in optical L_bol (hence R and P_j/L_bol). With N=5 and non-uniform slopes, the evolutionary inference should be stated more cautiously in the Abstract and Summary, or supported by a quantitative test (e.g., Spearman rank on absolute νL_ν vs λ_Edd for the same five objects, and a statement of how many of the 54 persistent sources have any multi-epoch optical constraint).
- §4.5 and Figs. 10–11: FIRST/VLASS arcsecond fluxes predominantly trace kpc-scale jets/lobes, while CL transitions act on the inner flow and pc-scale core—a limitation the paper correctly notes. The timelines show that radio epochs often do not cleanly bracket a single documented CL event, and intervening unrecorded transitions are possible. The conclusion that instantaneous CL changes do not regulate jet activity is therefore under-constrained by these data. Either reframe the claim as applying to kpc-scale radio emission only, or add a quantitative accounting of how many of the 58 sources have radio epochs that straddle the spectroscopic CL window versus lying entirely before/after it.
- §4.2 Eq. (5) and §4.1: P_j is applied to the full radio-detected sample, including the radio-quiet minority for which the authors state it is only an upper limit on mechanical power. Because the elevated P_j/L_bol distribution (Fig. 4) and the comparison to typical AGNs/transients are central results, the paper should either recompute the K-S tests after excluding log R < 1 sources or show that the efficiency offset is unchanged when restricted to the radio-loud majority. The same section should state how sensitive Fig. 4 is to the fixed α_R = −0.7 k-correction used in Eq. (4).
minor comments (6)
- §3.2 and Fig. 1: The continuum-to-line variability share of 1:1 and α_O = −1.5 are reasonable but free parameters; a short sensitivity check (e.g., share 0.5–1.5 or α_O = −1.0/−2.0) would strengthen confidence in the photometric L_5100 values used for λ_Edd.
- Table 1 / Table A: Several entries have incomplete or missing log L_5100 / log M_BH (dashes) and inconsistent uncertainty formatting; a uniform note on upper limits and non-detections would help reproducibility.
- Fig. 9 caption and §4.4: The K-S p-value quoted for CL-AGNs vs typical AGNs (p ≈ 0.79) is consistent with no difference, but the sentence structure that pairs it with the much smaller p vs transients is easy to misread; separate the two comparisons more clearly.
- §2.3.3: The radio-transient comparison sample is reduced from ≳50 literature objects to 22 after quality cuts; list the exact selection criteria (required ancillary quantities) so the cut is reproducible.
- Typographical/notation: “poseudo-magnitude” in Fig. 1; “muti-epoch” in Table 1 caption; mixed use of λ_Edd vs L_bol/L_Edd; occasional missing spaces in object names (e.g., J113615.08-002314.2 vs J113615.08–002314.2).
- §4.3.3 / Fig. 8: The TDE-like interpretation of J113615.08–002314.2 is appropriately cautious; a brief quantitative upper limit on He II variability (or non-detection) would make the spectroscopic argument sharper.
Circularity Check
Observational comparison paper: Pj/Lbol, R, and λ_Edd are standard derived quantities; parent CL-AGN catalogs are self-cited but do not force the radio result by construction.
specific steps
-
self citation load bearing
[Section 2.2 (parent sample construction)]
"We construct a parent sample of changing-look AGNs by compiling all reported CL-AGNs from the literature. This compilation includes 1092 sources identified through optical spectroscopic variability and multi-wavelength diagnostics (e.g., … W.-J. Guo et al. 2024, 2025; Q. Yang et al. 2025; Q. Dong et al. 2025; Z.-Q. Chen et al. 2026)."
A non-negligible fraction of the 1092-source parent catalog is drawn from the present authors’ own recent CL-AGN papers. This is ordinary sample assembly, not a uniqueness claim or a fitted parameter re-used as a prediction; the radio results (detection rate, Pj/Lbol distributions, multi-epoch tracks) are measured independently of how the optical CL sample was assembled. Flagged only as minor self-citation, not load-bearing circularity.
full rationale
The paper is an empirical multi-survey comparison. Radio luminosities use a fixed α_R = −0.7 k-correction (Eq. 4); jet power uses the external Rusinek et al. (2017) scaling (Eq. 5); bolometric luminosity and Eddington ratio use the standard Richards et al. (2006) and Greene & Ho (2005) relations (Eqs. 6–7). None of these parameters is fitted to the CL-AGN radio data and then re-presented as a prediction. Control samples (SDSS DR14 quasars; literature radio-transient catalogs of Nyland, Wołowska, Zhang) are external. The parent sample of 1092 CL-AGNs is assembled from literature that includes the authors’ own catalogs (Guo et al. 2024, 2025; Chen et al. 2025, 2026), which is normal sample construction and does not define the radio-kinetic-efficiency or anti-correlation results by construction. The source-by-source anti-correlation (five objects, Fig. 7) and the population-level statements are direct measurements, not tautologies. No uniqueness theorem, ansatz, or fitted-input-as-prediction pattern is present. Score 1 reflects only the minor, non-load-bearing self-citation of the parent CL-AGN lists.
Axiom & Free-Parameter Ledger
free parameters (7)
- radio spectral index α_R =
-0.7
- bolometric correction L_bol = 9.26 L_5100 =
9.26
- jet kinetic power prefactor and exponent in Eq. 5 =
5e22, exponent 6/7
- optical continuum slope α_O =
-1.5
- continuum-to-line variability share ratio =
1:1
- radio flux detection threshold and match radii =
2 mJy; 5″/3″
- quasi-simultaneous matching window =
1000 days
axioms (6)
- domain assumption CL spectral type transitions are driven primarily by accretion-rate changes rather than variable obscuration.
- domain assumption Host-galaxy starlight contribution is constant over decade timescales.
- domain assumption Narrow [O III] λ5007 luminosity is stable and can flux-calibrate spectra across facilities.
- domain assumption Virial black-hole mass from broad Hβ (Greene & Ho 2005) is adequate for λ_Edd ranking.
- domain assumption Compact FIRST/VLASS morphologies plus high Dn(4000) imply nuclear (not star-formation) radio origin.
- ad hoc to paper Empirical jet-power–radio-luminosity relation remains meaningful for the radio-quiet minority as an upper limit on mechanical power.
read the original abstract
Changing-look active galactic nuclei (CL-AGNs) provide a unique opportunity to probe the coupling between accretion flows and relativistic jets in supermassive black holes. We investigate the long-term radio behavior of CL-AGNs over approximately 20 years by combining FIRST and VLASS observations with quasi-simultaneous optical spectroscopy and photometry. From a parent sample of 1092 CL-AGNs, we identify 58 sources with radio detections. Radio-detected CL-AGNs exhibit systematically higher radio kinetic efficiency, quantified by \(P_{\rm j}/L_{\rm bol}\), than both typical radio-detected AGNs and radio transients, consistent with their preference for low Eddington ratios. At the population level, the expected anti-correlation between radio emission and accretion rate is weak. However, a clear source-by-source anti-correlation emerges in a small subset of CL-AGNs with continuous multi-epoch coverage. We further identify four radio transients, including both radio turn-on and turn-off events, and one source exhibiting a multiwavelength flare that may be indicative of tidal disruption event-like activity. These results suggest that radio activity in CL-AGNs is not governed by instantaneous accretion state changes but is instead regulated by long-term accretion history and jet evolution, with additional stochastic or transient channels contributing in rare cases.
Figures
Reference graph
Works this paper leans on
-
[1]
D., van Velzen, S., Horesh, A., & Zauderer, B
Alexander, K. D., van Velzen, S., Horesh, A., & Zauderer, B. A. 2020, Radio Properties of Tidal Disruption Events, SSRv, 216, 81, doi: 10.1007/s11214-020-00702-w
-
[2]
Amirkhanian, V. R. 1985, Frequency Dependence of the Statistics of Radio Sources, Ap&SS, 108, 125, doi: 10.1007/BF00650124
-
[3]
Blundell, K. M. 2005, Radio Variability of Radio-quiet and Radio-loud Quasars, ApJ, 618, 108, doi: 10.1086/425859
doi:10.1086/425859 2005
-
[4]
H., White, R
Becker, R. H., White, R. L., & Helfand, D. J. 1994, The VLA’s FIRST Survey, in Astronomical Society of the Pacific Conference Series, Vol. 61, Astronomical Data Analysis Software and Systems III, ed. D. R. Crabtree, R. J. Hanisch, & J. Barnes, 165
1994
-
[5]
H., White, R
Becker, R. H., White, R. L., & Helfand, D. J. 1995, The FIRST Survey: Faint Images of the Radio Sky at Twenty
1995
-
[6]
Centimeters, ApJ, 450, 559, doi: 10.1086/176166
-
[7]
Bellm, E. C., Kulkarni, S. R., Graham, M. J., et al. 2019, The Zwicky Transient Facility: System Overview, Performance, and First Results, PASP, 131, 018002, doi: 10.1088/1538-3873/aaecbe
-
[8]
Bennert, N., Falcke, H., Schulz, H., Wilson, A. S., & Wills, B. J. 2002, Size and Structure of the Narrow-Line Region of Quasars, ApJL, 574, L105, doi: 10.1086/342420
doi:10.1086/342420 2002
-
[9]
Birmingham, S., Ward, C., Nyland, K., et al. 2025, The birth of young radio jets in changing-look AGN: a population study, arXiv e-prints, arXiv:2507.01355, doi: 10.48550/arXiv.2507.01355
-
[10]
K., Nicholl, M., Berger, E., et al
Blanchard, P. K., Nicholl, M., Berger, E., et al. 2017, PS16dtm: A Tidal Disruption Event in a Narrow-line Seyfert 1 Galaxy, ApJ, 843, 106, doi: 10.3847/1538-4357/aa77f7
-
[11]
Blandford, R. D., & K¨ onigl, A. 1979, Relativistic jets as compact radio sources., ApJ, 232, 34, doi: 10.1086/157262
doi:10.1086/157262 1979
-
[12]
Chen, Y., Gaensler, B. M., Clarke, T., et al. 2025, Searching for Radio Transients with Inverted Spectra in Epoch 1 of VLASS and VCSS, and Identification of a Sample of Candidate Relativistic Nuclear Transients, ApJ, 987, 170, doi: 10.3847/1538-4357/add924
-
[13]
Chen, Z.-Q., Guo, W.-J., Zou, H., Liu, M.-F., & Yuan, Q.-R. 2025, Searching for Changing-look AGN Candidates through Optical and Mid-infrared Variability, Research in Astronomy and Astrophysics, 25, 095012, doi: 10.1088/1674-4527/ade952
-
[14]
2026, Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument
Chen, Z.-Q., Jin, J.-J., Guo, W.-J., et al. 2026, Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. V. Dramatic Variability in High-ionization Broad Emission Lines, ApJS, 282, 28, doi: 10.3847/1538-4365/ae23cb
-
[15]
Condon, J. J. 1992, Radio emission from normal galaxies., ARA&A, 30, 575, doi: 10.1146/annurev.aa.30.090192.003043
-
[16]
Corbel, S., Nowak, M. A., Fender, R. P., Tzioumis, A. K., & Markoff, S. 2003, Radio/X-ray correlation in the low/hard state of GX 339-4, A&A, 400, 1007, doi: 10.1051/0004-6361:20030090
-
[17]
Dempsey, R., & Zakamska, N. L. 2018, The size-luminosity relationship of quasar narrow-line regions, MNRAS, 477, 4615, doi: 10.1093/mnras/sty941
-
[18]
Dong, Q., Zhang, Z.-X., Gu, W.-M., Sun, M., & Zheng, Y.-G. 2025, Newly Discovered Changing-look Active Galactic Nuclei from SDSS and LAMOST Survey, ApJ, 986, 160, doi: 10.3847/1538-4357/add331 17 T able A.Radio and Optical Properties of the Radio-detected CL-AGNs Object NamezMJD spec1 MJDspec2 Spec Tranf peak fint RMS MJD Survey logL 5100 logM BH J001553....
-
[19]
Fender, R. P., Belloni, T. M., & Gallo, E. 2004, Towards a unified model for black hole X-ray binary jets, MNRAS, 355, 1105, doi: 10.1111/j.1365-2966.2004.08384.x
-
[20]
Gordon, Y. A., Boyce, M. M., O’Dea, C. P., et al. 2021, A Quick Look at the 3 GHz Radio Sky. I. Source Statistics from the Very Large Array Sky Survey, ApJS, 255, 30, doi: 10.3847/1538-4365/ac05c0
-
[21]
J., Pulgarin-Duque, L., Anderson, S
Green, P. J., Pulgarin-Duque, L., Anderson, S. F., et al. 2022, The Time Domain Spectroscopic Survey: Changing-look Quasar Candidates from Multi-epoch Spectroscopy in SDSS-IV, ApJ, 933, 180, doi: 10.3847/1538-4357/ac743f
-
[22]
Greene, J. E., & Ho, L. C. 2005, A Comparison of Stellar and Gaseous Kinematics in the Nuclei of Active Galaxies, ApJ, 627, 721, doi: 10.1086/430590
doi:10.1086/430590 2005
-
[23]
Guo, H., Liu, X., Shen, Y., et al. 2019, Constraining sub-parsec binary supermassive black holes in quasars with multi-epoch spectroscopy - III. Candidates from continued radial velocity tests, MNRAS, 482, 3288, doi: 10.1093/mnras/sty2920
-
[24]
Guo, W.-J., Zou, H., Fawcett, V. A., et al. 2024, Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. I. Sample from the Early Data, ApJS, 270, 26, doi: 10.3847/1538-4365/ad118a
-
[25]
Guo, W.-J., Zou, H., Greenwell, C. L., et al. 2025, Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. II. Statistical Properties from the First Data Release, ApJS, 278, 28, doi: 10.3847/1538-4365/adc124
-
[26]
J., White, R
Helfand, D. J., White, R. L., & Becker, R. H. 2015, The Last of FIRST: The Final Catalog and Source
2015
-
[27]
Identifications, ApJ, 801, 26, doi: 10.1088/0004-637X/801/1/26
-
[28]
Ho, L. C. 2008, Nuclear activity in nearby galaxies., ARA&A, 46, 475, doi: 10.1146/annurev.astro.45.051806.110546 Ivezi´ c,ˇZ., Menou, K., Knapp, G. R., et al. 2002, Optical and Radio Properties of Extragalactic Sources Observed by the FIRST Survey and the Sloan Digital Sky Survey, AJ, 124, 2364, doi: 10.1086/344069
Pith/arXiv arXiv doi:10.1146/annurev.astro.45.051806.110546 2008
-
[29]
Jana, A., Ricci, C., Venselaar, S. M., et al. 2025, ALMA observation of an evolving magnetized corona in the radio-quiet changing-state active galactic nucleus NGC 1566, A&A, 699, A62, doi: 10.1051/0004-6361/202554491
-
[30]
2021, Mid-infrared Outbursts in Nearby Galaxies (MIRONG)
Jiang, N., Wang, T., Dou, L., et al. 2021, Mid-infrared Outbursts in Nearby Galaxies (MIRONG). I. Sample Selection and Characterization, ApJS, 252, 32, doi: 10.3847/1538-4365/abd1dc
-
[31]
Kauffmann, G., Heckman, T. M., White, S. D. M., et al. 2003, Stellar masses and star formation histories for 10 5 galaxies from the Sloan Digital Sky Survey, MNRAS, 341, 33, doi: 10.1046/j.1365-8711.2003.06291.x
-
[32]
Kawamuro, T., Ricci, C., Imanishi, M., et al. 2022, BASS XXXII: Studying the Nuclear Millimeter-wave Continuum Emission of AGNs with ALMA at Scales ≲100-200 pc, ApJ, 938, 87, doi: 10.3847/1538-4357/ac8794
-
[33]
Kellermann, K. I. 1966, The radio source 1934-63, Australian Journal of Physics, 19, 195, doi: 10.1071/PH660195
doi:10.1071/ph660195 1966
-
[34]
Kellermann, K. I., & Pauliny-Toth, I. I. K. 1969, The Spectra of Opaque Radio Sources, ApJL, 155, L71, doi: 10.1086/180305
doi:10.1086/180305 1969
-
[35]
Komossa, S., & Grupe, D. 2023, Extreme accretion events: TDEs and changing−look AGN, Astronomische Nachrichten, 344, e20230015, doi: 10.1002/asna.20230015 K¨ ording, E. G., Jester, S., & Fender, R. 2006, Accretion states and radio loudness in active galactic nuclei: analogies with X-ray binaries, MNRAS, 372, 1366, doi: 10.1111/j.1365-2966.2006.10954.x
-
[36]
Lacy, M., Baum, S. A., Chandler, C. J., et al. 2020, The Karl G. Jansky Very Large Array Sky Survey (VLASS). Science Case and Survey Design, PASP, 132, 035001, doi: 10.1088/1538-3873/ab63eb
-
[37]
Laha, S., Ricci, C., Mather, J. C., et al. 2025a, X-ray properties of coronal emission in radio quiet active galactic nuclei, Frontiers in Astronomy and Space Sciences, 11, 1530392, doi: 10.3389/fspas.2024.1530392
-
[38]
Laha, S., Meyer, E., Roychowdhury, A., et al. 2022, A
2022
-
[39]
Radio, Optical, UV, and X-Ray View of the Enigmatic Changing-look Active Galactic Nucleus 1ES 1927+654 from Its Pre- to Postflare States, ApJ, 931, 5, doi: 10.3847/1538-4357/ac63aa
-
[40]
Laha, S., Meyer, E. T., Sadaula, D. R., et al. 2025b, Multiwavelength Observations of a Jet Launch in Real Time from the Post-changing-look Active Galaxy 1ES 1927+654, ApJ, 981, 125, doi: 10.3847/1538-4357/adaea0
-
[41]
LaMassa, S. M., Cales, S., Moran, E. C., et al. 2015, The Discovery of the First “Changing Look” Quasar: New Insights Into the Physics and Phenomenology of Active Galactic Nucleus, ApJ, 800, 144, doi: 10.1088/0004-637X/800/2/144
-
[42]
Leloudas, G., Dai, L., Arcavi, I., et al. 2019, The Spectral Evolution of AT 2018dyb and the Presence of Metal Lines in Tidal Disruption Events, ApJ, 887, 218, doi: 10.3847/1538-4357/ab5792 24
-
[43]
Li, R., Ho, L. C., Ricci, C., et al. 2022, The Host Galaxy and Rapidly Evolving Broad-line Region in the Changing-look Active Galactic Nucleus 1ES 1927+654, ApJ, 933, 70, doi: 10.3847/1538-4357/ac714a
-
[44]
Liu, Z., Liu, H.-Y., Cheng, H., Qiao, E., & Yuan, W. 2020, The large amplitude X-ray variability in NGC 7589: possible evidence for accretion mode transition, MNRAS, 492, 2335, doi: 10.1093/mnras/stz3579 L´ opez-Navas, E., S´ anchez-S´ aez, P., Ar´ evalo, P., et al. 2023, Improving the selection of changing-look AGNs through multiwavelength photometric va...
-
[45]
Maccarone, T. J. 2003, Do X-ray binary spectral state transition luminosities vary?, A&A, 409, 697, doi: 10.1051/0004-6361:20031146
-
[46]
MacLeod, C. L., Ross, N. P., Lawrence, A., et al. 2016, A systematic search for changing-look quasars in SDSS, MNRAS, 457, 389, doi: 10.1093/mnras/stv2997
-
[47]
1998, The Demography of Massive Dark Objects in Galaxy Centers, AJ, 115, 2285, doi: 10.1086/300353
Magorrian, J., Tremaine, S., Richstone, D., et al. 1998, The Demography of Massive Dark Objects in Galaxy Centers, AJ, 115, 2285, doi: 10.1086/300353
doi:10.1086/300353 1998
-
[48]
2018, A unified accretion-ejection paradigm for black hole X-ray binaries
Marcel, G., Ferreira, J., Petrucci, P.-O., et al. 2018, A unified accretion-ejection paradigm for black hole X-ray binaries. II. Observational signatures of jet-emitting disks, A&A, 615, A57, doi: 10.1051/0004-6361/201732069
-
[49]
Masci, F. J., Laher, R. R., Rusholme, B., et al. 2019, The Zwicky Transient Facility: Data Processing, Products, and Archive, PASP, 131, 018003, doi: 10.1088/1538-3873/aae8ac
-
[50]
H., Knigge, C., Higginbottom, N., et al
Matthews, J. H., Knigge, C., Higginbottom, N., et al. 2020, Stratified disc wind models for the AGN broad-line region: ultraviolet, optical, and X-ray properties, MNRAS, 492, 5540, doi: 10.1093/mnras/staa136
-
[51]
McKinney, J. C., & Narayan, R. 2007, Disc-jet coupling in black hole accretion systems - I. General relativistic magnetohydrodynamical models, MNRAS, 375, 513, doi: 10.1111/j.1365-2966.2006.11301.x
-
[52]
Merloni, A., Heinz, S., & di Matteo, T. 2003, A Fundamental Plane of black hole activity, MNRAS, 345, 1057, doi: 10.1046/j.1365-2966.2003.07017.x
-
[53]
Meyer, E. T., Laha, S., Shuvo, O. I., et al. 2025, Late-time Radio Brightening and Emergence of a Radio Jet in the Changing-look AGN 1ES 1927+654, ApJL, 979, L2, doi: 10.3847/2041-8213/ad8651
-
[54]
N., Doel, P., Gutierrez, G., et al
Miller, T. N., Doel, P., Gutierrez, G., et al. 2024, The Optical Corrector for the Dark Energy Spectroscopic
2024
-
[55]
Instrument, AJ, 168, 95, doi: 10.3847/1538-3881/ad45fe
-
[56]
2015, PyBDSF: Python Blob Detection and Source Finder,, Astrophysics Source Code Library, record ascl:1502.007
Mohan, N., & Rafferty, D. 2015, PyBDSF: Python Blob Detection and Source Finder,, Astrophysics Source Code Library, record ascl:1502.007
2015
-
[57]
Nicholl, M., Wevers, T., Oates, S. R., et al. 2020, An outflow powers the optical rise of the nearby, fast-evolving tidal disruption event AT2019qiz, MNRAS, 499, 482, doi: 10.1093/mnras/staa2824
-
[58]
Noda, H., & Done, C. 2018, Explaining changing-look AGN with state transition triggered by rapid mass accretion rate drop, MNRAS, 480, 3898, doi: 10.1093/mnras/sty2032
-
[59]
Nyland, K., Dong, D. Z., Patil, P., et al. 2020, Quasars That Have Transitioned from Radio-quiet to Radio-loud on Decadal Timescales Revealed by VLASS and FIRST, ApJ, 905, 74, doi: 10.3847/1538-4357/abc341
-
[60]
Panessa, F., Baldi, R. D., Laor, A., et al. 2019, The origin of radio emission from radio-quiet active galactic nuclei, Nature Astronomy, 3, 387, doi: 10.1038/s41550-019-0765-4 Planck Collaboration, Aghanim, N., Akrami, Y., et al. 2020, Planck 2018 results. VI. Cosmological parameters, A&A, 641, A6, doi: 10.1051/0004-6361/201833910
-
[61]
Rakshit, S., Stalin, C. S., & Kotilainen, J. 2020, Spectral Properties of Quasars from Sloan Digital Sky Survey Data Release 14: The Catalog, ApJS, 249, 17, doi: 10.3847/1538-4365/ab99c5
-
[62]
Ren, W., Guo, H., Shen, Y., et al. 2024, Prior-informed Active Galactic Nucleus Host Spectral Decomposition Using PyQSOFit, ApJ, 974, 153, doi: 10.3847/1538-4357/ad6e76
-
[63]
Ricci, C., & Trakhtenbrot, B. 2023, Changing-look active galactic nuclei, Nature Astronomy, 7, 1282, doi: 10.1038/s41550-023-02108-4
-
[64]
Ricci, C., Chang, C.-S., Kawamuro, T., et al. 2023, A Tight Correlation between Millimeter and X-Ray Emission in Accreting Massive Black Holes from ¡100 mas Resolution ALMA Observations, ApJL, 952, L28, doi: 10.3847/2041-8213/acda27
-
[65]
T., Lacy, M., Storrie-Lombardi, L
Richards, G. T., Lacy, M., Storrie-Lombardi, L. J., et al. 2006, Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars, ApJS, 166, 470, doi: 10.1086/506525
doi:10.1086/506525 2006
-
[66]
Ruan, J. J., Anderson, S. F., Eracleous, M., et al. 2019, The Analogous Structure of Accretion Flows in Supermassive and Stellar Mass Black Holes: New Insights from Faded Changing-look Quasars, ApJ, 883, 76, doi: 10.3847/1538-4357/ab3c1a
-
[67]
Ruan, J. J., Anderson, S. F., Cales, S. L., et al. 2016, Toward an Understanding of Changing-look Quasars: An Archival Spectroscopic Search in SDSS, ApJ, 826, 188, doi: 10.3847/0004-637X/826/2/188 25
-
[68]
Godfrey, L. 2017, On the efficiency of jet production in FR II radio galaxies and quasars, MNRAS, 466, 2294, doi: 10.1093/mnras/stw3330
-
[69]
2014, The jet-disc connection in AGN, MNRAS, 445, 81, doi: 10.1093/mnras/stu1759
Sbarrato, T., Padovani, P., & Ghisellini, G. 2014, The jet-disc connection in AGN, MNRAS, 445, 81, doi: 10.1093/mnras/stu1759
-
[70]
Shastri, P., Wilkes, B. J., Elvis, M., & McDowell, J. 1993, Quasar X-Ray Spectra Revisited, ApJ, 410, 29, doi: 10.1086/172721
-
[71]
Shen, Y., Richards, G. T., Strauss, M. A., et al. 2011, A Catalog of Quasar Properties from Sloan Digital Sky Survey Data Release 7, ApJS, 194, 45, doi: 10.1088/0067-0049/194/2/45
-
[72]
Shen, Y., Hall, P. B., Horne, K., et al. 2019, The Sloan Digital Sky Survey Reverberation Mapping Project: Sample Characterization, ApJS, 241, 34, doi: 10.3847/1538-4365/ab074f
-
[73]
2017, Mid-infrared Variability of Changing-look AGNs, ApJL, 846, L7, doi: 10.3847/2041-8213/aa85de
Sheng, Z., Wang, T., Jiang, N., et al. 2017, Mid-infrared Variability of Changing-look AGNs, ApJL, 846, L7, doi: 10.3847/2041-8213/aa85de
-
[74]
Sheng, Z., Wang, T., Jiang, N., et al. 2020, Initial Results from a Systematic Search for Changing-look Active Galactic Nuclei Selected via Mid-infrared Variability, ApJ, 889, 46, doi: 10.3847/1538-4357/ab5af9
-
[75]
Shimwell, T. W., Hardcastle, M. J., Tasse, C., et al. 2022, The LOFAR Two-metre Sky Survey. V. Second data release, A&A, 659, A1, doi: 10.1051/0004-6361/202142484
-
[76]
Sikora, M., Stawarz, L., & Lasota, J.-P. 2007, Radio Loudness of Active Galactic Nuclei: Observational Facts and Theoretical Implications, ApJ, 658, 815, doi: 10.1086/511972
doi:10.1086/511972 2007
-
[77]
H., Fagrelius, P., Fanning, K., et al
Silber, J. H., Fagrelius, P., Fanning, K., et al. 2023, The Robotic Multiobject Focal Plane System of the Dark Energy Spectroscopic Instrument (DESI), AJ, 165, 9, doi: 10.3847/1538-3881/ac9ab1
-
[78]
Sniegowska, M., Czerny, B., Bon, E., & Bon, N. 2020, Possible mechanism for multiple changing-look phenomena in active galactic nuclei, A&A, 641, A167, doi: 10.1051/0004-6361/202038575
-
[79]
Wang, S., Woo, J.-H., Gallo, E., et al. 2024, Identifying Changing-look AGNs Using Variability Characteristics, ApJ, 966, 128, doi: 10.3847/1538-4357/ad3049 Wo lowska, A., Kunert-Bajraszewska, M., Mooley, K. P., et al. 2021, Caltech-NRAO Stripe 82 Survey (CNSS). V. AGNs That Transitioned to Radio-loud State, ApJ, 914, 22, doi: 10.3847/1538-4357/abe62d
-
[80]
Wu, Y., Yang, J., & Sun, X. H. 2023, A Statistical Study of A Large Sample of Changing-look Active Galactic Nuclei with Multi-frequency Radio Sky Surveys, Acta Astronomica Sinica, 64, 7
2023
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.