Astrophysics Brown Bag Lunch Talk 12/6/2021: Speakers: Mojegan Azadi (Harvard Smithsonian CfA) And Guglielmo Mastroserio (Caltech)
Monday, December 6, 2021 12:00 – 12:30pm
Mojegan Azadi, Harvard Smithsonian CfA
Disentangling the AGN and star-formation contributions in powerful radio galaxies
Abstract: I will describe a multi-wavelength analysis of active galactic nuclei (AGN) incorporating X-ray, optical, infrared, and radio data to estimate AGN and their host galaxies’ physical properties. My newly developed, state-of-the-art AGN spectral energy distribution fitting code (ARXSED) models the emission from both the AGN and their host galaxies from X-ray to radio wavelengths, including nuclear accretion disk, torus, star-formation, and the extended radio lobes. I will present the results of fitting this model to a sample of radio-loud quasars at 1< z <2. This multi-wavelength approach allows us to address one of the long-standing questions of AGN science on the relationship between the growth of the supermassive black holes and their host galaxies.
Bio: I am a postdoc at Harvard-CfA. My research is primarily on supermassive black holes, and their impact’s on galaxies. Before CfA, I was a grad student at UC San Diego, and my PhD work was on the multi-wavelength analysis of active galaxies. I am originally from Iran and received my master’s degree in gravitational physics from the University of Tehran.
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12:30 – 1:00pm
Guglielmo Mastroserio, Caltech
Modelling X-ray reverberation lags in accreting black holes
Abstract: Accreting black holes show characteristic features that result from reprocessing of hard X-ray photons by the accretion disk. The shape of these features depends on the properties of the accretion disc and the black holes. Even though X-ray ‘reflection’ energy spectra have been extensively modelled to constrain the geometry of these systems and the spin of black holes, X-ray reverberation mapping lacks from the same accuracy in modelling. Here I present the reltrans model that aims to self-consistently explain the reverberation time lags observed in accreting black holes together with other different sources of lags probably connected to the mass accretion rate in the disc.
Bio: My journey begins in Italy where I studied Physics at the University of Milan. After finishing my master, I moved to the Netherlands. I had a lot of fun studying accreting black holes during my PhD at the University of Amsterdam. Now, I’m a postdoc at Caltech where I spent the last 2 years working in the NuSTAR group.
Speakers
- Mojegan Azadi , Harvard Smithsonian CfA
- Guglielmo Mastroserio , (Caltech)