High Energy Astrophysics and Cosmology in the era of all-sky surveys

Session

Physics of AGN

8 Oct 2024, 09:00

5. Multi-messenger emission from AGN

Paolo Padovani

08/10/2024, 09:00

Invited

After the 2017 association between the blazar TXS 0506+056 and high-energy IceCube neutrinos, there has been a surge of research exploring the potential link between blazars and neutrinos. In 2022, somewhat surprising evidence emerged for neutrino emission from the nearby prototype Seyfert II galaxy, NGC 1068. This raises the question: which, if any, AGN are neutrino emitters, and why? What...

77. Application of Neural Networks to Study Blazars

Narek Sahakyan (ICRANET-Armenia IO)

08/10/2024, 09:30

Invited

The integration of Artificial Intelligence (AI) into astronomy and astrophysics marks a transformative era in the exploration of the Universe, enhancing the analysis of vast data sets with unparalleled efficiency and precision. AI is revolutionizing the usability of observational data, expanding our understanding of various cosmic phenomena. Blazar research particularly benefits from the...

31. Where does AGN activity occur within the cosmic web?

Meredith Powell (Leibniz Institute for Astrophysics Potsdam (AIP))

08/10/2024, 10:00

Regular

The cosmic environments of accreting supermassive black holes provide powerful insights on the intertwined histories of structure growth, black hole growth, and galaxy evolution. One way to probe these environments is via the spatial clustering of active galactic nuclei (AGN). Using new data from the BASS and HETDEX wide-field surveys, I will present recent AGN clustering measurements as a...

14. Reflection-dominated Compton-thick AGN Candidates in the SRG/eROSITA Lockman Hole Survey

Mikhail Belvedersky (IKI RAS, HSE University)

08/10/2024, 11:20

Regular

We search for reflection-dominated Compton-thick active galactic nuclei (CT AGN) candidates in the Lockman Hole region using the SRG/eROSITA Lockman Hole survey data. To this end, we selected sources with anomalously hard photon indexes in the 0.3 $-$ 8.0 keV band, untypical for type I AGN. In particular, we required that the upper end of the 90% error interval did not exceed a fudicial...

4. Low-mass galaxy interactions trigger AGN activity

Marko Micic

08/10/2024, 11:35

Regular

Recent discoveries of supermassive black holes existing less than 500 million years after the Big Bang represent a major puzzle. How did these black holes grow so much in such a short time? In this talk, I will discuss how the early Universe environmental conditions could have led to an accelerated black hole growth. The prevailing wisdom suggests that the early Universe is dominated by dwarf...

25. X-ray variability of the jet power in NGC 1275

Elena Fedorova (1) INAF-OAR 2) AO KNU)

08/10/2024, 11:50

Regular

We present a comprehensive multi-wavelength analysis of NGC 1275/Perseus A, focusing on its X-ray and gamma-ray emission over a 24-year period (2000-2024). Our study utilizes data from multiple space-based observatories, including SUZAKU, XMM-Newton, SWIFT, and INTEGRAL. The X-ray data observed by Suzaku/XIS were treated using a model-independent method for separating the spectral components...

76. Electron-positron pair creation in electrosphere of compact astrophysical objects

Gregory Vereshchagin

08/10/2024, 12:05

Invited

We will discuss pair creation by electrically neutral compact astrophysical objects, having sufficiently sharp positively charged surface boundary to create an electrosphere with overcritical electric field. Two types of energy sources will be considered: heat and radial electromagnetic perturbation. Implications for astrophysical observations will be outlined.

79. The Multiwavelength Luminosity-luminosity correlation of AGNs can shed light on the relation between the AGN jet and accretion disk emisions

Vahe' Petrosian (Stanford University)

Invited

AGN jets are detected via their radio and/or gamma-ray emissions while the accretion disks by their X-ray to IR radiation. The relation between these two mechanism can be investigated using broad band spectra of bright sources or through population studies, in particular the luminosity-luminosity (L-L) correlation at different wavelength for large samples of AGNs. In general, there is a large...

66. The X-ray-UV Luminosity relation of AGNs revisited

Dr Maria Chira (IAASARS, National Obs. Athens)

Regular

In this work we will scrutinize the universality of the well-known non-linear relation between the UV and X-ray luminosity of AGNs. The LX-LUV correlation provides insights on the energy generating mechanisms and structural characteristics of AGNs, but it has also been proposed as a cosmological probe, under the assumption that it is redshift independent. However, recent works on the subject...