Active Galactic Nuclei (AGN) are an essential component of current theories of galaxy evolution. Specifically, the energy released by material accreting onto the central supermassive black hole (SMBH) is believed to generate outflows which suppress star formation throughout the host galaxy. However, the mechanisms by which activity in the central parsecs of a galaxy impacts gas thousands of times further away is poorly understood. To better understand the physics of "AGN feedback," and its various manifestations, we have begun a multi-scale, multi-wavelength investigation of AGN outflows in a sizable and diverse sample of relatively nearby galaxies. In this talk, I will discuss this project and present our initial findings -- including a "bonus" discovery of the interaction between an AGN jet and a satellite galaxy.

Location: ASU Praha-Spořilov

There is ample evidence that supermassive black holes (SMBHs) exist in the nuclei of all massive galaxies and that the masses of the SMBHs scale with properties of their host galaxies, e.g. stellar velocity dispersion (M_BH - σ*), bulge mass (M_BH - M_Bulge), and stellar mass (Μ_ΒΗ - Μ_*). These scaling relations are believed to be the result of co-evolution between the SMBH and its host galaxy. However, the situation in low mass and dwarf galaxies is less clear, with large uncertainties in both the occupation fraction and scaling relations. In addition, if the relations hold true, low mass galaxies should host intermediate mass black holes (IMBHs). Understanding black holes in low mass galaxies is crucial for understanding galaxy evolution, formation of seed black holes in the early universe, and the search for IMBHs. In this talk I will discuss the low mass end of the BH-galaxy scaling relations and search for IMBHs with a focus on a peculiar galaxy, IC 750, a near-by low mass galaxy. I will present a multi-wavelength study of IC 750 which shows that it hosts a 1 x 10^5 M_sun black hole which is undermassive by one to two orders of magnitude below the BH-galaxy scaling relations. I will also show results on the accretion processes in the system and summarize searches for other such systems. I will conclude with the implications of these results on theories of BH-galaxy co-evolution and future prospects.

Location: ASU Praha-Spořilov

TBD

Location: GPS/Sporilov

Quasars are the most luminous subset of the Active Galactic Nuclei (AGN) population and represent the most rapid phase of supermassive black hole (SMBH) growth. Strong observational evidence supports a connection between SMBH accretion and the evolution of their host galaxies, where obscured quasars are expected to play a key role. However, this role has not yet been fully understood since large quasar samples have biases, typically against obscured AGN, low-luminosity AGNs, etc. In this talk, I will present results from a complete and unbiased sample of high-luminosity mid-infrared quasars at z=1−3. By combining multiwavelength data from X-rays to radio wavelengths, including ALMA submillimeter observations, we probe the physical properties of both the AGN and their host galaxies, revealing fundamental differences in the radio and star-formation properties between obscured and unobscured populations. I will discuss how these findings challenge the standard AGN orientation model and point toward possible evolutionary links among quasar populations. With the objective of pushing forward obscured quasar research, I will then introduce and show the first results of the 4MOST IR AGN survey, the first large-scale optical spectroscopic survey targeting obscured IR AGN. I will finish my talk by discussing how upcoming multiwavelength large-scale surveys will allow us to improve our understanding of the relationship between different AGN populations and galaxies.

Location: ASU Spořilov 101

online připojení https://us02web.zoom.us/j/3464248686

Understanding the co-evolution of active galactic nuclei (AGN) and their host galaxies requires the robust decomposition of their respective emission to reliable constrain the AGN and host galaxy physical properties. Leveraging the unique NIR capabilities of Euclid’s Quick Data Release (Q1), I performed spectral energy distribution (SED) fitting to simultaneously constrain the properties of AGN and their hosts. Moreover, I present a new method to assess and improve the reliability of the measurements, based on simulated SEDs built from combined quasar and galaxy observations. I quantify how AGN emission impacts physical property estimations and demonstrate that SED fitting serves as a powerful diagnostic for AGN identification, achieving 85% purity and completeness. Furthermore, a comparative analysis of AGN selected via different methods reveals that these techniques probe partially distinct populations, highlighting the importance of multi-wavelength, multi-method approaches to mitigate selection biases in studies of galaxy evolution. Finally, we investigate the X-ray to mid-infrared luminosity relation and the evolution of the stellar mass–bolometric luminosity correlation across cosmic time. These results validate the utility of Euclid for constructing large, homogeneous AGN samples, providing a crucial foundation for mapping the co-evolution of supermassive black holes and their hosts over a wide range of redshifts. I will conclude my talk by showcasing how the community can leverage this catalogue for future AGN studies.

Location: ASU Sporilov, 101

online připojení https://us02web.zoom.us/j/3464248686

Location: Seminar room, Prague