Illuminating the Active Universe: Multi-Wavelength and Multi-Messenger Insights into AGN

Session

AGN Environments

16 Sept 2026, 14:40

Auditorium Telescopium (ESO)

39. When Jets Are Not Enough: Neutrino Emission and Accretion in AGN

Tullia Sbarrato (INAF - Osservatorio Astronomico di Brera)

16/09/2026, 14:40

Invited

AGN have long been regarded as prime candidates for high-energy astrophysical neutrino emission, particularly jetted AGN, which make up about 10% of the population. The association of a neutrino and a neutrino flux excess with the blazar TXS 0506+056 confirmed this expectation and revived the debate on jet particle composition. The multimessenger picture changed significantly when the most...

19. Kinetic simulations of mildly relativistic weakly magnetized shocks in AGN jets

Artem Bohdan (Max Planck Institute for Plasma Physics)

16/09/2026, 15:10

Regular

Plasma shock waves are among the most promising sites for efficient particle acceleration in extragalactic jets. In mildly relativistic electron–ion shocks, electrons can be heated to high Lorentz factors, providing a natural explanation for the large minimum electron energies often required to model the emission of BL Lac objects (Arbet-Engels et al. 2025). In this work, we present results...

40. Numerical Simulations of Restarted Jets: Dynamics, Particle Acceleration, and Emission

Prathamesh Ratnaparkhi (IUCAA, Pune, India)

16/09/2026, 15:30

Regular

Radio observations of restarted jets in active galaxies reveal complex morphologies and spectral signatures that trace episodic jet activity. We investigate these phenomena using high-resolution 3D simulations with the PLUTO code, combined with Lagrangian macroparticles to model non-thermal electrons. This framework enables spatially resolved modelling of synchrotron emission, spectral index,...

61. Changing Accretion in AGN within the Disc–Wind Framework

Sruthi Suresh (University of Melbourne)

16/09/2026, 15:50

Regular

We present a multiwavelength study of 798 Type 1 and 2607 Type 2 active galactic nuclei (AGN), combining optical spectroscopy with X-ray data from eROSITA and infrared observations from WISE. We investigate a scenario in which AGN accretion can weaken, disappear, and reform, driving structural changes across the nucleus with characteristic timescales. We find ~1000 low luminosity optically...

14. Probing Obscured AGN with Far-Infrared Line Emission: Predictions from Multiphase ISM Modeling

Karolina Garcia (NCSA, University of Illinois)

16/09/2026, 16:40

Regular

The far-infrared (FIR) regime offers a unique, dust-penetrating window into AGN activity that is inaccessible to X-ray, optical, and radio surveys. While multi-wavelength approaches have been transformative for unobscured AGN demographics, the heavily obscured population (believed to dominate at cosmic noon) remains poorly characterized. FIR fine-structure lines are powerful...

22. AGN Activity and Multi-Phase Gas in Overdense Structures at z~2-4

Andrea Travascio (INAF)

16/09/2026, 17:00

Regular

Overdense cosmic structures at high redshift (z~2-4) offer a unique laboratory to study the baryon cycle during the peak of galaxy assembly. This work connects the environmental impact of massive structures with the microscopic physical state of the circumgalactic medium (CGM) through a two-fold approach. First, we investigate the MQN01 protocluster, an exceptionally dense region hosting a...