INTER-UNIVERSITY  CENTRE  FOR  ASTRONOMY  AND  ASTROPHYSICS
(An Autonomous Institution of the University Grants Commission)

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  SEMINAR

 

Ms. Gunjan Tomar

Ph.D. Student, Raman Research Institute, Bangalore
 
High-Energy Observations of Low-Luminosity Active Galactic Nuclei
 
 

In the nearby universe, low-luminosity active galactic nuclei (LLAGNs) dominate, which are characterized by their low accretion rates and often misaligned jets. Due to their faintness, the high-energy (HE) properties of these sources remain less explored than those of their brighter counterparts. Multi-wavelength observations of their jets serve as a crucial probe into the physical mechanisms in these extreme environments. Recent advancements in gamma-ray observations by Fermi-LAT have significantly improved our understanding. I will present a detailed broadband study of two recently identified gamma-ray emitters, NGC 315 and NGC 4261, which hints at the presence of extended gamma-ray emissions, previously only known in two bright radio galaxies. Additionally, I will discuss temporal SED variations in another LLAGN, M81*, which shows behavior similar to high-synchrotron-peaked blazars, suggesting a potential universal jet mechanism across AGN luminosities. Finally, I will touch on our recent very high energy (VHE; >100 GeV) detections of a few more radio galaxies expanding the sample of misaligned VHE emitters despite modest Doppler boosting, and conclude with insights on their implications for VHE emission processes and AGN jet physics.

 
IUCAA Lecture Hall, Bhaskara 3
November 12, 2024, 16:00 hrs.