C. Ricci

Pushing Variability Searches to Extreme Dwarf Galaxies with the Vera C. Rubin Observatory Data Preview 2

Fan Zou, W. N. Brandt, Elena Gallo +15

Galaxies with stellar masses $M_{⋆} < 1 0^{8} M_{⊙}$ , hereafter referred to as extreme dwarf galaxies (EDGs), represent one of the least explored regimes in the search for accreting…

Multi-epoch Detection of an Ultra-fast Inflow in ESP 39607: Evidence for an Accretion Cascade

Alessandro Peca, Michael J. Koss, Roberto Serafinelli +10

We present simultaneous XRISM, XMM-Newton, and NuSTAR observations of ESP 39607, a Seyfert 2 galaxy at $z = 0.201$ . XRISM/Resolve reveals two absorption features near 4.7 and 4.9 k…

Super-Eddington Accretion and Early-Stage Feedback in Ton S180

Pierpaolo Condò, Giacomo Venturi, Eleonora Parlanti +15

Narrow-line Seyfert 1 (NLSy1) galaxies are key laboratories for studying rapid supermassive black hole (SMBH) growth and active galactic nucleus (AGN) feedback at high accretion ra…

Relativistic outflows power a quasi-periodic eruption: constraints on energetics, mass loss, and emission mechanisms

Joheen Chakraborty, Erin Kara, Wenbin Lu +17

Quasi-periodic eruptions (QPEs) are recurring bursts of X-ray radiation originating from supermassive black holes (SMBHs). They are an unprecedented type of structured, high-amplit…

The emergence of X-ray emission lines during relativistic radio-jet formation in the changing-look active galactic nucleus 1ES 1927+654

Dev R. Sadaula, Sibasish Laha, Eileen T. Meyer +27

We present results from a comprehensive multi-wavelength monitoring campaign of the changing-look active galactic nucleus 1ES 1927+654 during the onset and evolution of a relativis…

Extreme Variability Reveals How the Eddington Ratio Regulates Coronal Power in Active Galactic Nuclei

Arghajit Jana, Claudio Ricci, Franz E. Bauer +13

The bolometric luminosity ( $L_{bol}$ ) of active galactic nuclei (AGNs) is a key tracer of accretion physics, but its direct determination is often hindered by limited spectral…

The SKA-VLBI Perspective on Radio-Quiet AGN

Francesca Panessa, Tao An, James Petley +21

The accretion-ejection mechanism in Active Galactic Nuclei (AGN) remains a central open problem in astrophysics, tied to the role of AGN feedback in galaxy formation and evolution.…

Population synthesis of active galactic nuclei based on the radiation-regulated unification model

D. Gerolymatou, S. Paltani, C. Ricci +1

X-ray surveys of active galactic nuclei (AGNs) provide direct constraints on the properties of individual AGNs, such as their emission, obscuration, and accretion rate. Previous AG…

Resolved UV-Optical HST Imaging and Spectral Energy Distribution Modeling of Nearby BAT Active Galactic Nuclei

Connor Auge, Michael Koss, Kriti K. Gupta +17

We use high-resolution UV-to-optical imaging from the Hubble Space Telescope (HST) to construct spatially resolved spectral energy distributions (SEDs) for seven nearby ( $z < 0.07$ )…

Persistence of the Millihertz X-ray Quasi-Periodic Oscillation in the Active Galactic Nucleus 1ES 1927+654

Megan Masterson, Erin Kara, William N. Alston +15

1ES 1927+654 is an extreme active galactic nucleus (AGN) that has defied our canonical expectations for how AGN appear across the electromagnetic spectrum and how they vary on shor…

BASS. LI. Cool gas supply of HI-massive local Seyfert galaxies

Jeein Kim, Aeree Chung, O. Ivy Wong +19

We present neutral atomic hydrogen (HI) imaging observations of 22 HI-rich ( $M_{HI} ≳ 1 0^{9.7} M_{⊙}$ ), hard X-ray-selected local Seyferts to explore how cool gas is su…

A positive period derivative in the quasi-periodic eruptions of ZTF19acnskyy

Joheen Chakraborty, Saul A. Rappaport, Riccardo Arcodia +9

We report the first direct measurement of the period derivative in a quasi-periodic eruption (QPE), finding a smoothly increasing period with $\dot{P}\approx (1.7\pm 0.02)\times10^…

astro-ph.HE2026★ 5 cited

Multi-wavelength properties of changing-state active galactic nuclei: I. the evolution of soft excess and X-ray continuum

Arghajit Jana, Claudio Ricci, Alessia Tortosa +11

Changing-state active galactic nuclei (CSAGNs) exhibit rapid variability, with mass accretion rates that can change by several orders of magnitude in a few years. This provides us…

astro-ph.GA2025★ 3 cited

BASS.L. Near-infrared Data Release 3: A Spectral Atlas and Characterization of AGN

Jarred Gillette, Michael J. Koss, Darshan Kakkad +18

We present an analysis of near-infrared (NIR) emission-line properties, AGN diagnostics, and circumnuclear gas dynamics for 453 hard X-ray selected (14 $-$ 195 keV) AGN from the BAT…

Predicting Quasar Counts Detectable in the LSST Survey

Guodong Li, Roberto J. Assef, W. N. Brandt +11

The Legacy Survey of Space and Time (LSST), being conducted by the Vera C. Rubin Observatory, is a wide-field multi-band survey that will revolutionize our understanding of extraga…

astro-ph.GA2025★ 3 cited

Scalable and Robust Multiband Modeling of AGN Light Curves in Rubin-LSST

Weixiang Yu, John J. Ruan, Colin J. Burke +22

The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) will monitor tens of millions of active galactic nuclei (AGNs) for a period of 10 years with an average caden…

astro-ph.HE2025★ 3 cited

The Advanced X-ray Imaging Satellite (AXIS) Community Science Book

Michael Koss, Nafisa Aftab, Steven W. Allen +395

The AXIS Community Science Book represents the collective effort of 592 scientists worldwide to define the transformative science enabled by the Advanced X-ray Imaging Satellite (A…

Molecular Gas in Major Mergers Hosting Dual and Single AGN at <10 kpc Nuclear Separations

Makoto A. Johnstone, Ezequiel Treister, Franz E. Bauer +24

We present high-resolution ( $\sim$ 50 $-$ 100 pc) Atacama Large Millimeter Array (ALMA) observations of $^{12}$ CO(2-1) or $^{12}$ CO(1-0) emission in seven local ( $z$ $≲$ 0.05)…

BASS LIV. Physical Properties of AGN-Hosting Galaxy Mergers from Multiwavelength SED Fitting

Marco Troncoso, Ezequiel Treister, Alejandra Rojas +17

Galaxy mergers are believed to play an important role in triggering rapid supermassive black hole (SMBH) growth. As merging nuclei approach each other, the physical properties of t…

VAR-PZ: Constraining the Photometric Redshifts of Quasars using Variability

S. Satheesh-Sheeba, R. J. Assef, T. Anguita +33

The Vera C. Rubin Observatory LSST is expected to discover tens of millions of new Active Galactic Nuclei (AGNs). The survey's exceptional cadence and sensitivity will enable UV/op…

BASS LII: The prevalence of double-peaked broad lines at low accretion rates among hard X-ray selected AGN

Charlotte Ward, Michael J. Koss, Michael Eracleous +18

A fraction of active galactic nuclei (AGN) have double-peaked H $α$ , H $β$ and Mg II broad lines attributed to emission from rotating gas in the accretion disk. Using optical spectro…

BASS LIII: The Eddington Ratio as the Primary Regulator of the Fraction of X-ray Emission in Active Galactic Nuclei

Kriti Kamal Gupta, Claudio Ricci, Alessia Tortosa +20

Active galactic nuclei (AGN) emit radiation via accretion across the entire energy spectrum. While the standard disk and corona model can somewhat describe this emission, it fails…

astro-ph.GA2025★ 8 cited

BASS. XLIX. Characterization of highly luminous and obscured AGNs: local X-ray and [NeV] $λ$ 3426 emission in comparison with the high-redshift Universe

Alessandro Peca, Michael J. Koss, Kyuseok Oh +21

We present a detailed analysis of the most luminous and obscured Active Galactic Nuclei (AGNs) detected in the ultra-hard X-ray band (14-195 keV) by Swift/BAT. Our sample comprises…