Speaker: Niranjan Roy (University of Connecticut)

Host: Tabassum Tanvir 

Title: Synthetic emission lines tracing multi-phase interstellar medium and outflows in the FIRE cosmological simulations.

Abstract: Unveiling the drivers of galaxy growth is one of the key science goals of Astrophysics this decade. How did the clumpy early galaxies evolve to the diversity of morphologies we see today? How does feedback from massive stars and black holes impact galaxy evolution? We investigate these questions with detailed synthetic observations of FIRE (Feedback In Realistic Environments) simulated galaxies at a range of redshifts. The FIRE simulations resolve the multi-phase interstellar medium of galaxies while capturing their cosmological environment and self-consistently reproduce a range of observed galaxy properties, providing a unique platform to produce synthetic integral field unit (IFU) data for one-to-one comparisons to observations by JWST and other IFU surveys. We leverage the non-equilibrium chemistry solver CHIMES and the 3D Monte-Carlo line radiative transfer code RADMC-3D to model the emission, propagation, and absorption of spectral lines from the FIR to the UV regimes, along with stellar emission and absorption, scattering, and thermal emission from dust grains. Our goal is to recover intrinsic galaxy properties from mock emission line IFU observations of FIRE galaxies and test observational inferences of the physical properties of galaxies. This comparison of observationally inferred versus intrinsic galaxy properties will greatly inform the use of emission line tracers across the FIR to UV range. Such data will be important to calibrate the reduction and analysis pipelines of IFU instruments that are already bringing a paradigm shift in our understanding of galaxy evolution.

Bio: Niranjan is a fourth-year grad at the University of Connecticut Physics department, working with Prof. Daniel Anglés-Alcázar on creating and analyzing mock emission line observations of galaxies from cosmological zoom-in simulations. He completed his master’s in physics from the University of Massachusetts Dartmouth, his second master’s in physics from UConn, and his baccalaureate from Bangladesh University of Engineering and Technology.