Eventi

13 MARZO 2025 ore 11:30
Colloquium

Probing the various shades of jet activity in Active Galactic Nuclei

Dr. Francesca Panessa (INAF-Istituto di Astrofisica e Planetologia Spaziali, Italia)
Probing the various shades of jet activity in Active Galactic Nuclei

The evolution of each massive galaxy in the Universe is strictly connected to the activity of the supermassive black hole located at its centre. During their diverse accretion phases, SMBH occasionally eject plasma in the form of outflow and/or a collimated jet. It is estimated that only approximately 10% of active galactic nuclei (AGN) have the ability to launch powerful relativistic jets that shine in the radio band and emit synchrotron radiation. We refer to them as radio-loud (RL) AGNs. However, low power radio emission is also observed in radio-quiet (RQ) AGNs. Overall, AGN show a large variety of radio properties and morphologies, with sources exhibiting compact cores, jets, knots and extended diffuse emission in a wide range of strengths and sizes ranging from subparsec up to kiloparsec and even megaparsec scales. The incredible wealth of radio facilities currently available is offering a new panorama on the radio properties of RL and RQ AGN. In RL AGN, the number of sources showing episodes of restarting activity is rapidly increasing allowing for a more precise determination of the duty cycle of jet activity. In RQ AGN, the increase in sensitivity of radio interferometers and pioneering studies of radio light curves, are allowing us to investigate the radio nuclear properties and to probe the plethora of physical mechanisms, such as star formation, accretion disk winds, coronal disk emission, low-power jets. All these mechanisms will be probed with unprecedented sensitivity and spatial resolution with SKA, in particular by exploiting its VLBI capabilities at low and high frequencies.

 

Breve CV della Dr. Francesca Panessa:

Dr. Francesca Panessa si è laureata all'Università di Bologna in Astronomia, dove ha poi ottenuto il suo Dottorato in Astronomia. Ha poi lavorato all'Institute of Astronomy in Cambridge (UK), all'Harvard Center for Astrophysics (Boston) e all'Instituto de Física de Cantabria, Spagna. E' un'esperta nello studio dei fenomeni di accrescimento ed emissione in buchi neri super massivi, in particolare nello studio di emissione multi frequenza dal radio ai raggi X.  Attualmente lavora all'INAF-Istituto di Astrofisica e Planetologia Spaziali (IAPS) di Roma, come primo ricercatore all'interno del gruppo GRAL.