Zobrazeno 1 - 10
of 12 157
pro vyhledávání: '"Petropoulou, A."'
Super-Eddington accretion onto stellar-mass compact objects powers fast outflows in Ultra-Luminous X-ray sources (ULXs). Such outflows, which can reach mildly relativistic velocities, are often observed forming bubble structures. Wind bubbles are exp
Externí odkaz:
http://arxiv.org/abs/2411.08762
A ubiquitous feature of accreting black hole systems is their hard X-ray emission which is thought to be produced through Comptonization of soft photons by electrons and positrons in the vicinity of the black hole, in a region with optical depth of o
Externí odkaz:
http://arxiv.org/abs/2410.12638
(Abridged) Sgr A$^\star$ is the electromagnetic counterpart of the accreting supermassive black hole in the Galactic center. Its emission is variable in the near-infrared (NIR) and X-ray wavelengths on short timescales. The physical origin of NIR and
Externí odkaz:
http://arxiv.org/abs/2410.09971
The supermassive black hole Sgr A* at the center of our galaxy produces repeating near-infrared flares that are observed by ground and space based instruments. This activity has been simulated in the past with Magnetically Arrested Disk (MAD) models
Externí odkaz:
http://arxiv.org/abs/2407.14312
Publikováno v:
Astrophys. J. 974, 75 (2024)
The cores of active galactic nuclei (AGN) are potential accelerators of 10-100 TeV cosmic rays, in turn producing high-energy neutrinos. This picture was confirmed by the compelling evidence of a TeV neutrino signal from the nearby active galaxy NGC
Externí odkaz:
http://arxiv.org/abs/2407.01678
Autor:
Rodrigues, Xavier, Karl, Martina, Padovani, Paolo, Giommi, Paolo, Paiano, Simona, Falomo, Renato, Petropoulou, Maria, Oikonomou, Foteini
A correlation has been reported between the arrival directions of high-energy IceCube events and gamma-ray blazars classified as intermediate- and high-synchrotron-peaked BL Lacs. Subsequent studies have investigated the optical properties of these s
Externí odkaz:
http://arxiv.org/abs/2406.06667
Recent advances in numerical simulations of magnetically arrested accretion onto supermassive black holes have shed light on the formation and dynamics of magnetospheric current sheets near the black hole horizon. By considering the pair magnetizatio
Externí odkaz:
http://arxiv.org/abs/2406.01211
Autor:
Karavola, Despina, Petropoulou, Maria
The ''twin birth'' of a positron and an electron by a photon in the presence of a nucleus, known as Bethe-Heitler pair production, is a key process in astroparticle physics. The Bethe-Heitler process offers a way of channeling energy stored in a popu
Externí odkaz:
http://arxiv.org/abs/2401.05534
Jets from supermassive black holes in the centers of active galaxies are the most powerful persistent sources of electromagnetic radiation in the Universe. To infer the physical conditions in the otherwise out-of-reach regions of extragalactic jets w
Externí odkaz:
http://arxiv.org/abs/2311.06181
Autor:
Marcotulli, Lea, Ajello, Marco, Böttcher, Markus, Coppi, Paolo, Costamante, Luigi, Di Gesu, Laura, Errando, Manel, García, Javier A., Gokus, Andrea, Liodakis, Ioannis, Madejski, Greg, Madsen, Kristin, Moretti, Alberto, Middei, Riccardo, McBride, Felicia, Petropoulou, Maria, Rani, Bindu, Sbarrato, Tullia, Stern, Daniel, Vasilopoulos, Georgios, Zacharias, Michael, Zhang, Haocheng, Collaboration, the HEX-P
A fraction of the active supermassive black holes at the centers of galaxies in our Universe are capable of launching extreme kiloparsec-long relativistic jets. These jets are known multiband (radio to $\gamma$-ray) and multimessenger (neutrino) emit
Externí odkaz:
http://arxiv.org/abs/2311.04801