Weekly issue

Week 26, 2026

Jun 22–28, 2026

Week 26, 2026 includes 9 curated papers, centered on high-z, LRD, QSO.

2606.26098v1

A Population of Little Red Dot-like Quasars in SDSS

Quinn O. Casey, Ryan C. Hickox, Nikko J. Cleri, Jonathan H. Cohn, David M. Alexander, Emmanuel Durodola, Kelly E. Whalen, Raphael E. Hviding, Tonima Tasnim Ananna

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Digest

Using the overlap between SDSS ugriz filters at z≈0.4 and 0.8 and the JWST bands used to select z∼5 little red dots, this paper builds a large sample of about 1300 SDSS quasar analogs dubbed Local Red Dots, or LoRDs. A V-shaped subset of 244 objects shows higher-order Balmer absorption and [Ne V] λ3426 emission, highlighting spectral structure that would likely be missed at JWST/PRISM resolution while preserving the broad-Balmer, red-continuum phenomenology that defines LRDs. Their composite SED departs from a typical quasar in the rest-frame UV and optical but agrees in the NIR, and it matches an LRD stack with fits consistent with a reddened AGN plus host galaxy, with or without an added cool blackbody. Just as importantly, the LoRDs are X-ray detected at rates comparable to ordinary quasars, and the paper argues that current LRD X-ray upper limits are loose enough that similar sources would often remain undetected, tempering claims that LRD-like colors necessarily imply intrinsic X-ray weakness.

Open paper page arXiv abstract arXiv PDF Highlighted PDF

Key figures to inspect

Figure 1. Use this to show the selection logic. It demonstrates the rest-frame filter overlap between JWST and SDSS and then maps where the LoRDs sit in color space relative to the control quasars, making clear how the local analog sample is defined rather than assumed.
Figure 3. This is the key spectral-evidence figure for the V-shaped subset. The stacked spectra isolate the Balmer-limit-centered continuum shape and show the higher-order Balmer absorption plus [Ne V] emission that strengthen the case that LoRDs reproduce distinctive LRD-like spectroscopic behavior.
Figure 5. This figure is the cleanest synthesis of the SED argument because it directly compares the LoRD and LRD composite SEDs and shows the exploratory component fits. It matters because the paper’s bottom-line physical interpretation rests on the close match between the local analog stack and the observed LRD stack.
Figure 6. Include this for the X-ray result, which is one of the paper’s most consequential takeaways. The comparison of Hβ-based expectations, LoRD detections and limits, and published LRD upper limits makes the paper’s point that present LRD non-detections do not by themselves prove anomalous X-ray weakness.
Figure 7. This figure captures the observational-resolution caveat in the most concrete way by degrading SDSS LoRD spectra to JWST/PRISM resolution and comparing them directly with observed LRD spectra. It shows why narrow absorption and line-diagnostic structure visible locally could be washed out in current high-redshift data while leaving the overall LRD-like spectral shape intact.

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2606.21105v1

Little Red Dots as Supermassive Analogs of SS 433

Shuying Zhou, Mouyuan Sun, Xihan Ji, Ya-Ping Li, Luis C. Ho, Roberto Maiolino, Zhen-Yi Cai, Hai-Cheng Feng, Manqi Fu, Wei-Min Gu, Tong Liu, Junfeng Wang, Jianfeng Wu, Yongquan Xue

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Digest

This paper argues that little red dots are the supermassive, high-redshift analogs of SS 433: hyper-Eddington accretors seen at high inclination, where a puffed-up inner disk self-shields the central engine. In that geometry, the model naturally reproduces the observed LRD mix of V-shaped and soft optical SEDs, X-ray weakness, apparent sub-Eddington accretion, and Balmer breaks, while anisotropic radiation escaping along polar directions can still ionize the broad-line region. The same framework unifies low-inclination or lower-accretion-rate counterparts as little blue dots or more ordinary AGN. A key payoff is a set of directly testable predictions, including stronger Balmer breaks for broader lines, greater line than continuum variability, suppressed variability in LRDs relative to LBDs, and intrinsic luminosities that are higher than the edge-on view suggests.

Open paper page arXiv abstract arXiv PDF Highlighted PDF

Key figures to inspect

Figure 1. Use this as the conceptual anchor figure. It lays out the paper’s unified central-engine picture across SS 433, ultraluminous supersoft sources, LRDs, and LBD-like counterparts, and it explains why self-shielding, inclination, and the loss of strong winds at supermassive scales together generate the observed red continuum, Balmer break, and anisotropic ionizing field.
Figure 2. This figure is the cleanest mass-scaling bridge between SS 433 and LRDs. It shows that the maximum visible inner-disk temperatures along high-inclination sightlines fall into the effective-temperature range inferred for LRDs, supporting the core claim that the same hyper-Eddington physics can be scaled from stellar-mass to supermassive black holes.
Figure 4. This is the main radiative-transfer evidence figure. It demonstrates that changing inclination alone can turn the simulated spectrum into the soft, red, approximately blackbody-like continuum associated with LRDs, while also producing a distinct Balmer break at high inclination.
Figure 6. Choose this as the strongest synthesis and observational-comparison figure. It connects Balmer break strength to inclination and luminosity in the model and then places the available LRD measurements on the same plane, directly supporting the paper’s prediction that stronger Balmer breaks arise preferentially in more edge-on systems.
Figure 7. This figure captures one of the paper’s most distinctive observational tests. By scaling the SS 433 thermal-timescale variability to supermassive black holes, it predicts that LRD optical variability should occur over several rest-frame years, which is important for separating this scenario from alternatives and for interpreting why continuum changes may be muted relative to line variability.

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2606.21614v1

Little Red and Blue Dots: AGN-excited narrow lines, Lyman-$α$ emission, and resemblance to standard quasars

Sophia Geris, Roberto Maiolino, Xihan Ji, Guido Risaliti, Giorgio Lanzuisi, Francesco D'Eugenio, Yuki Isobe, Gareth Jones, Anishya Harshan, Matilde Brazzini, Ignas Juodžbalis, Jan Scholtz, Pierluigi Rinaldi, Hannah Übler, William Baker, Andrew J. Bunker, Marcella Brusa, Stefano Carniani, Stephane Charlot, Mirko Curti, Andrea Comastri, Emma Curtis Lake, Roberto Gilli, Kevin Hainline, Piero Madau, Stefano Marchesi, Giovanni Mazzolari, Lorenzo Napolitano, Eleonora Parlanti, Laura Pentericci, Cristina Ramos Almeida, Brant Robertson, Maddie S. Silcock, Roberta Tripodi, Giacomo Venturi, Cristian Vignali, Fabio Vito, Yongda Zhu

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Using 36 JWST-selected Little Red and Blue Dots in GOODS at 2.26<z<7.89, this paper asks whether the two classes are fundamentally different or instead variants of the same accreting black-hole population. The main result is that both LRDs and LBDs occupy narrow-line diagnostic loci consistent with AGN excitation despite being extremely X-ray weak, while weak HeII points to a softer ionizing spectrum than in standard quasars. LRDs additionally show Lyα stronger than ordinary star-forming galaxies, with a broad Lyα component matching broad Hα, implying that ionizing radiation escapes to the surrounding ISM rather than being fully trapped in a closed cocoon. The broad-line comparison is the key discriminator: LBDs look broadly quasar-like, whereas LRDs shift to higher broad-Hα equivalent width and Balmer decrement, disfavoring fully enclosing gas-envelope models and favoring obscured, clumpy, or equatorial-geometry interpretations in which LRDs can be dustier analogs of LBDs and standard isotropic bolometric estimates break down.

Open paper page arXiv abstract arXiv PDF Highlighted PDF

Key figures to inspect

Figure 1. Use this as the selection-definition figure. It shows exactly how the authors separate LRDs, LBDs, and more classical reddened AGN in rest-frame UV versus optical slope space, while also marking the stacked spectra and the two Rosetta Stone objects that recur throughout the paper.
Figure 3. This is the cleanest overview of the paper's X-ray weakness result. It places both the individual sources and the stacks in bolometric-to-X-ray luminosity space relative to local quasars, NLS1s, SEAMBHs, and the few X-ray detections, making the mismatch with standard expectations and the bolometric-correction discussion immediately visible.
Figure 7. This figure carries the core narrow-line evidence that both LRDs and LBDs are AGN excited. The multi-panel BPT and related diagnostic diagrams show that the stacks and many individual objects land in AGN-consistent regions once low-metallicity offsets are allowed for, while also emphasizing that some line ratios differ from the local AGN locus.
Figure 13. This is the most important comparison figure for the paper's interpretation of the two classes. By plotting broad-Hα equivalent width against the broad Balmer decrement for the stacks, Rosetta Stones, and SDSS quasar distribution, it makes clear that LBDs are broadly quasar-like while LRDs occupy a more extreme but still quasar-overlapping tail, which is central to the obscured-LBD and non-fully-enclosed-geometry conclusions.
Figure 18. Use this as the strongest Lyα-physics figure. The matched red-wing velocity profiles of Lyα and Hα in the LRD stack argue that the broad Lyα component is linked to the same broad-line region emission rather than being produced solely by resonant scattering, directly supporting the claim that AGN radiation escapes to ionize the surrounding gas.

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2606.20800v1

No hidden monsters: Probing recently-quenched galaxies for obscured AGN with JWST-PRIMER MIRI and NIRCam

Guillaume Hewitt, Omar Almaini, David Maltby, Emma Chapman, Thomas de Lisle, Pallavi Patil, Kate Rowlands, Maya Skarbinski, Elizabeth Taylor, Vivienne Wild, Adam C. Carnall, James S. Dunlop, Norman Grogin, Anton M. Koekemoer, Derek J. McLeod, Pablo G. Pérez-González

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This paper uses JWST-PRIMER MIRI F770W and F1800W imaging, together with eight NIRCam bands and three HST/ACS bands, to test whether 65 photometrically selected post-starburst galaxies in PRIMER-UDS at 1 < z < 2 hide dust-obscured AGN. The main result is strongly mass-dependent: most massive PSBs above 10^10 Msun have mid-IR colours consistent with ordinary quiescent galaxies and show no excess hot-dust emission, while lower-mass PSBs are brighter at 18 um in a way the authors attribute to residual star formation. AGN template experiments then turn that non-detection into a quantitative limit, implying any obscured AGN in the massive PSBs must be accreting below about 1 percent of Eddington. The paper therefore argues against a substantial hidden-AGN population in massive recently quenched galaxies and highlights F770W-F1800W as a simple, powerful passive-versus-star-forming diagnostic in this redshift range.

Open paper page arXiv abstract arXiv PDF Highlighted PDF

Key figures to inspect

Figure 1. Use this for the sample definition. It shows the stellar-mass versus redshift distribution of the PRIMER-UDS galaxies, the 65 PSBs within the F200W-selected parent sample, and the mass-completeness limits that frame where the high-mass and low-mass conclusions are reliable.
Figure 2. This is the clearest single statement of the paper’s observational result. It shows that F770W-F1800W cleanly separates passive and star-forming systems over the targeted redshift range and that the PSBs split by mass, with massive PSBs overlapping the quiescent locus while low-mass PSBs show a redder mid-IR excess.
Figure 4. Recommend this as the main diagnostic figure because it defines the MIR-excess versus MIR-non-excess populations in the full colour-colour space. It also shows where the PSBs sit relative to star-forming, quiescent, and X-ray-detected sources, making the case that the massive PSBs do not occupy an obviously AGN-like mid-IR regime.
Figure 6. This figure is central to the paper’s quantitative claim about hidden AGN. By overlaying obscured-AGN template tracks and probability contours on the PSB colour distribution, it visualizes why the MIR-non-excess massive PSBs are inconsistent with anything but very weak AGN activity and motivates the sub-1-percent Eddington-ratio limit.
Figure 7. Include this for the physical interpretation of the mass split. The rest-frame SED comparison shows that MIR-excess and MIR-non-excess PSBs have different mid-IR behaviour, supporting the paper’s conclusion that the excess seen in low-mass PSBs is better explained by residual star formation than by a buried AGN population.

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2606.23683v1

Little Red Dots on FIRE: Exploring the formation and observational signatures of ultra-compact early galaxies

Niranjan Chandra Roy, Daniel Anglés-Alcázar, Rachel K. Cochrane, Alexander J. Richings, Jonathan Mercedes-Feliz, Christopher C. Hayward, Claude-André Faucher-Giguère, Erini Lambrides, Robert Feldmann, Boon Kiat Oh, Andrew Marszewski, Guochao Sun, Kelcey Davis, Jed McKinney, Caitlin M. Casey, Tanio Díaz-Santos, Madisyn Brooks, Grace Farrell

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Using FIRE zoom-in simulations with 3D dust radiative transfer and synthetic line cubes, this paper asks how far a stellar-only explanation for little red dots can go. In progenitors of present-day group halos, the authors find transient z≈4–8 compaction phases lasting roughly 150–400 Myr that build ultra-compact, UV-bright stellar cores with R_eff<300 pc, V_circ>500 km s^-1, Balmer-break strengths around 2, blue UV slopes, ALMA-faint dust emission, and Balmer-line widths up to about 1500 km s^-1 from galaxy-scale dynamics. The key result is that these compact galaxies can reproduce a substantial subset of LRD observables without AGN, especially the UV continuum, moderate Balmer breaks, compactness, and intermediate broad-line widths. But the simulations do not recover the reddest rest-optical continua, the most extreme Balmer breaks or >2000 km s^-1 lines, or the broad-Balmer plus narrow-forbidden-line combination, so the paper argues for a hybrid compact-stars plus AGN interpretation for at least the bright massive LRD population.

Open paper page arXiv abstract arXiv PDF Highlighted PDF

Key figures to inspect

Figure 1. Use this as the physical setup and timescale figure. It shows how galaxy B2 enters a roughly 400 Myr ultra-compact phase with R_eff below 300 pc while the central 100 pc reaches extreme stellar surface density and V_circ≈800 km s^-1, directly motivating the paper’s claim that dissipative inflows can assemble LRD-like stellar cores.
Figure 2. This is the clearest population-level selection figure. It demonstrates that only the earlier-growing, more massive halo tracks enter the LRD-like region in the V_circ–R_eff plane at z≈4–8, linking the proposed stellar-only channel to progenitors of present-day group-scale environments rather than to the full simulated sample.
Figure 5. This figure is central for the observables case. It shows that during compact phases the synthetic SEDs produce Balmer breaks near the observed LRD range and blue UV slopes, while also making clear the role of dust and viewing angle in shaping the emergent continuum.
Figure 7. Choose this for the quantitative line-width test. It tracks Hβ and [O III] width evolution versus redshift and projection, showing that host-galaxy dynamics can push widths into the LRD-like intermediate regime but also illustrating the limit of the stellar-only scenario relative to the most extreme broad-line sources.
Figure 9. Include this as an important observational cross-check. It shows that the simulated compact phase remains undetectable in ALMA dust continuum in one-hour integrations across bands, supporting the paper’s claim that ALMA non-detections are compatible with ultra-compact stellar systems of this kind.

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2606.23778v1

Constraints on the Gas Geometry Surrounding Little Red Dots through Narrow-Line Diagnostics

Visal Sok, Erica J. Nelson, Mitchell C. Begelman, Jason Dexter, Francesco D'Eugenio, Jenny E. Greene, Joel Leja, Katherine E. Whitaker, Andrew J. Bunker, Pablo G. Pérez-González, Pierluigi Rinaldi, Alberto Torralba, Hannah Übler

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This paper tests whether the narrow-line emission in Little Red Dots can be explained purely by host-galaxy star formation if their central engine is buried inside a nearly unity-covering, optically thick gas envelope. Using high-S/N JWST/NIRSpec grating spectra for a sample of about 20 LRDs and multiple narrow-line diagnostics, the authors find that at least 40% show line ratios requiring high ionization parameter and electron temperature, with a further 15% also entering the AGN-like O I/Hα regime. At the same time, most objects still lack strong high-ionization emission, with He II/Hβ remaining low, so the ionizing spectrum is softer than a standard unobscured AGN. The combination argues against a uniform fully closed envelope and instead favors a clumpy or anisotropic gas geometry with lower-density escape channels that let hard photons reach the narrow-line gas.

Open paper page arXiv abstract arXiv PDF Highlighted PDF

Key figures to inspect

Figure 2. This is the core evidence figure because it places the LRD sample on the narrow-line diagnostic diagrams used to separate stellar photoionization from harder ionizing sources. Readers can see which objects lie outside the star-forming locus and how the measurements compare to stellar photoionization grids in ionization parameter and metallicity, making the paper’s main claim visually explicit.
Figure 4. This figure is the best synthesis of how the different diagnostics agree or disagree across the sample. The UpSet layout makes the lower-limit fractions easy to read, including the subset with high-ionization and high-electron-temperature signatures and the smaller subset where all three diagnostics collectively point to AGN or shocks, which is central to the paper’s population-level conclusion.
Figure 5. This schematic is the physical interpretation figure that translates the line-ratio results into a gas-geometry picture. It is the most direct visualization of the paper’s bottom line that LRDs likely have high-column regions producing the red continuum and Balmer-break-like features, plus lower-density channels that allow harder radiation to escape and power AGN-like narrow lines.
Figure 3. This figure is useful for showing object-by-object consistency rather than only aggregate fractions. The top and bottom panels quantify how many independent diagnostics tag each LRD as AGN-like and what fraction of available diagnostics do so, helping readers judge how robust the classifications are across an inhomogeneous observational sample.

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2606.25018v1

X-rays Mark the Spot: The Effects of Reduced Metallicity on X-ray AGN Obscuration at High Redshift

Yash A. Gursahani, Christopher S. Reynolds

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This paper uses 3D Monte Carlo radiative-transfer calculations to predict how X-rays from heavily obscured high-redshift AGN propagate through cold toroidal gas when the metallicity, torus opening angle, and column density are varied across the Compton-thick regime of N_H=10^24-10^25 cm^-2. The main result is that lowering metallicity, especially the iron abundance, can substantially reduce photoelectric losses and let many more X-ray photons escape, making deeply buried z~10 AGN more detectable in X-rays than solar-metallicity intuition would suggest. The geometric effect is not monotonic, because covering fraction and inclination set up a competition between repeated internal scatterings that isotropize the emission and escape through the opening that produces beaming. By also testing non-solar abundance patterns motivated by delayed Type Ia enrichment, the paper connects early chemical evolution directly to detectability forecasts for next-generation high-angular-resolution X-ray surveys.

Open paper page arXiv abstract arXiv PDF Highlighted PDF

Key figures to inspect

Figure 6. This is one of the clearest summary figures for the paper’s central claim: it shows how the transmitted 0.2-10 keV flux changes with redshift, opening angle, and inclination for Compton-thick obscuration at N_H=10^24 cm^-2, making the metallicity-driven transmission boost immediately visible in the observational band of interest.
Figure 8. Use this as the extreme-obscuration counterpart to Figure 6. It tests whether the low-metallicity transmission gain survives at N_H=10^25 cm^-2, which is essential for judging the detectability of the most deeply buried early AGN that motivate the paper.
Figure 10. This figure isolates the non-solar abundance-ratio experiment motivated by delayed Type Ia enrichment. It is important because it shows that iron-poor but alpha-element-rich mixtures can alter transmitted flux in ways that are not captured by a simple uniform metallicity rescaling.
Figure 11. This is the key line-diagnostic figure. It shows how Fe K equivalent width varies with line-of-sight column density and metallicity, while the shaded noise region makes clear where weak apparent line measurements should be treated cautiously.
Figure 13. This figure translates the radiative-transfer results into observability by comparing simulated AXIS and Chandra spectra for edge-on Compton-thick sources. It is the most direct bridge from the model grids to the paper’s bottom-line claim about detecting obscured z~10 AGN in future high-angular-resolution X-ray surveys.

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2606.27115v1

Clustering of high-redshift quasars with DESI DR2

M. Charles, P. Martini, A. J. Ross, D. H. Weinberg, J. Aguilar, S. Ahlen, D. Bianchi, D. Brooks, F. J. Castander, T. Claybaugh, A. Cuceu, A. de la Macorra, P. Doel, S. Ferraro, A. Font-Ribera, J. E. Forero-Romero, S. Gontcho A Gontcho, G. Gutierrez, J. Guy, C. Hahn, H. K. Herrera-Alcantar, K. Honscheid, C. Howlett, M. Ishak, R. Joyce, D. Kirkby, A. Kremin, M. Landriau, L. Le Guillou, M. E. Levi, M. Manera, A. Meisner, R. Miquel, J. Moustakas, A. D. Myers, S. Nadathur, N. Palanque-Delabrouille, W. J. Percival, F. Prada, I. Pérez-Ràfols, G. Rossi, L. Samushia, E. Sanchez, D. Schlegel, M. Schubnell, D. Sprayberry, G. Tarlé, B. A. Weaver, R. Zhou

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Using DESI DR2, this paper measures the clustering of a huge high-redshift quasar sample of about 715,000 objects at 2.0 < z < 3.5 and M1450 <= -19.94 mag. The headline result is a precise mean bias of b_Q(zbar = 2.48) = 3.61 +/- 0.01 plus strong redshift evolution, well described by b_Q(z) = a[(1 + z)^2 - 6.565] + b, while remaining consistent with quasars living in characteristic halos of roughly 10^12 Msun. The inferred duty cycle stays near 10^-2 across the sample, implying that only a small fraction of suitable halos host an active quasar at any given time. With the sample split by luminosity as well as redshift, the authors also report the first statistically significant luminosity dependence of quasar bias at these redshifts, but the trend is weak and notably softer than expected if quasar luminosity tracked halo mass tightly, making the measurement a sharp test of black hole light-curve and halo-occupation models.

Open paper page arXiv abstract arXiv PDF Highlighted PDF

Key figures to inspect

Figure 5. This is the cleanest summary of the paper's main clustering result: the redshift evolution of quasar bias across the four DESI DR2 bins, together with the best-fit b_Q(z) relation and comparison to earlier SDSS and DESI measurements. It is the most important figure for seeing both the precision of the new dataset and how the DESI result extends and regularizes the literature trend.
Figure 10. This figure most directly shows why the paper claims a statistically significant luminosity dependence at fixed redshift. By plotting pulls relative to the redshift-only model and fitting a nonzero slope with luminosity, it makes the significance of the deviation easy to see and ties the abstract's claim to a concrete diagnostic.
Figure 11. This is the key interpretation figure for the halo connection, translating the bias measurements into characteristic and minimum halo masses as a function of redshift and luminosity. It matters because the paper's conclusion that quasars inhabit halos of order 10^12 Msun with only modest evolution is one of the main physical takeaways.
Figure 12. This figure captures the duty-cycle inference, showing that the quasar duty cycle stays near 10^-2 across the redshift and luminosity bins. It is central for understanding the occupancy implication of the clustering analysis: most halos of the relevant mass are not hosting an active quasar at a given time.
Figure 13. This later comparison figure is especially valuable because it confronts the measured luminosity-binned bias with simple models having no scatter or large scatter between luminosity and halo mass. It helps explain why the observed luminosity dependence is described as weaker than a tight luminosity-halo mapping would predict, which is the paper's main model-level conclusion.

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2606.25896v1

Two years of shock interaction tracing three phases of evolution: the explosion of a Type IIn supernova, SN 2019vxm

Gitika Rameshan, Rishabh Singh Teja, D. K. Sahu, G. C. Anupama, Masayuki Yamanaka, Keiichi Maeda, Tatsuya Nakaoka, Sota Goto, Brajesh Kumar, Avinash Singh, Miho Kawabata, Koji S. Kawabata, Kenta Taguchi

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This paper follows the long-lived Type IIn SN 2019vxm for more than two years with UV-optical-NIR photometry and optical spectroscopy, showing a slow 45.9-day rise, a luminous peak at M_R about -20.3, and a total radiated energy of about 5x10^50 erg. Light-curve modeling and the broad H-alpha component both imply a massive interaction-powered event, with roughly 3-8 M_sun of circumstellar material and a minimum ejecta mass of about 3.88 M_sun. The spectroscopy resolves three phases: an initially interaction-dominated stage, a middle phase where photon scattering produces asymmetric Balmer cores with symmetric wings, and a late phase with IR brightening and strong suppression of red-side flux that points to dust at about 1500 K and around 4x10^16 cm. SN 2019vxm therefore stands out as an energetic, long-duration interacting supernova in which dense CSM interaction and dust obscuration continue to hide nebular ejecta signatures even at late times.

Open paper page arXiv abstract arXiv PDF Highlighted PDF

Key figures to inspect

Figure 2. Use this as the main observational overview figure. It establishes the unusually slow rise, the shallow early decline followed by a steeper optical fading, and the broad UV-to-NIR coverage that makes the later IR excess and long interaction timescale immediately visible.
Figure 3. This is one of the clearest summary figures for the paper’s late-time physics. The pseudo-bolometric decomposition and the optical-to-IR crossover directly support the claim that the event transitions into an IR-bright, dust-affected phase rather than remaining a purely optical interaction-powered transient.
Figure 6. This figure should be included because it carries the paper’s quantitative interaction modeling. It shows how the fitted light-curve model reproduces the long-lived emission and underpins the inferred massive CSM needed to power SN 2019vxm.
Figure 8. This is the key spectroscopic evolution figure for the three-phase story in the title and abstract. The progression from early symmetric Balmer profiles to profiles with symmetric wings and then to strong red-side suppression is the most direct visual evidence for the shift from pure interaction to scattering and finally to dust-affected line formation.
Figure 12. Include this later diagnostic figure because it quantifies the asymmetry instead of only showing it qualitatively. The mirrored H-alpha profiles, blue-to-red flux ratio, and Balmer decrement evolution are central for arguing that the late-time line shapes are not a minor fluctuation but a sustained physical change tied to obscuration and dense post-shock conditions.