Research Projects

I propose to study black hole (BH) demographics, from intermediate mass (IMBH) to supermassive scales (SMBH), and their impact on the tracers of large-scale structures (galaxies & galaxy clusters) across cosmic times. Active SMBHs, embedded within galaxy clusters, are studied through their interactions with the surroundings via active galactic nuclei (AGN) feedback. Conversely, quiescent BHs and those in intermediate mass regime are probed through observable signatures of tidal disruption events (TDEs) where tidal force of the BH disrupts nearby stars. My research expertise in both of these fields put me in a unique position to investigate BH populations across 4-6 orders in mass range, using the synergy between current and upcoming observations, theoretical models, and numerical simulations. I propose a unique avenue of studying galaxy evolution across cosmic time through associated TDE signatures. TDEs are excellent probes of the BH and host galaxy properties. However, the cosmological promise using high redshift TDEs is still lacking due to observational constraints. Moreover, TDEs caused by disruption of white dwarfs (WDs) provide a unique probe for studying IMBHs and globular clusters - a field that remains less explored. The plethora of the latest multi-wavelength telescopes like JWST, eROSITA, Vera Rubin Observatory, Nancy Grace Roman Space Telescope will revolutionise the field by discovering large populations of TDEs from across cosmological redshifts. To extract maximum knowledge from these discoveries, I will estimate TDE rates and emission models using my experience with high resolution cosmological simulations and advanced models of BHs, star formation and feedback. This will help to categorize TDEs caused by SMBHs and IMBHs, as well as TDEs from the central and off-nuclear BHs. I will also study the evolution of TDE rates, their connection to the host galaxy properties and AGN activities across wide redshift ranges. Finally, I will calculate their observed rates for different surveys parameters including survey area, magnitude limits and exposure times. This will guide us to design crucial observing strategies, characterisation of different TDE populations, detection of IMBHs and constraints on host galaxy properties. Understanding AGN feedback is crucial for unbiased, precise, cluster cosmology. In this regard, I will lead a thorough analysis of different modes of AGN feedback by analysing diffuse X-ray emissions from the galaxy clusters from high redshifts to the local universe using cosmological simulations. For a meaningful comparison with observations, using the analysis pipeline already developed by me, I will conduct a detailed photometric and spectroscopic analysis of simulated galaxy clusters followed by their synthetic observations for X-ray missions like XRISM, eROSITA, etc. Taken together, my work will help mitigate the systematic uncertainties in cluster cosmology introduced by poor understanding of central BH feedback.