My research focuses on the study of the impacts of the first massive stars and black holes on the physical properties of the interstellar medium of galaxies in the high-redshift (z>6) Universe. I tackle this problem with high-resolution cosmological simulations of galaxy formation with on-the-fly radiative transfer magnetohydrodynamics coupled to non-equilibrium thermochemistry with the novel RAMSES II code, for which I am a developer. I am particularly interested in using synthetic observations of these simulations to interpret sprectroscopic data from the James Webb Space Telescope. I am also a core member of the MEGATRON team.
I also actively research the process of cosmic Reionization, during which early galaxies were able to completely reionize the intergalactic medium. I have used synthetic observations of the SPHINX simulation to understand spectroscopic and Lyα diagnostics for the Lyman continuum escape fraction. Finally, I pioneered an approach using simulation based inference to directly infer the ionzing contributions of galaxies during the Epoch of Reionization. Using this method alongside public JWST data, I performed a new, self-consistent measurement of the history of Reionization.
I'm a British-New-Zealander DPhil student working with Professors Julien Devriendt and Adrianne Slyz. I am also the Graduate Teaching and Research Scholar in Physics at Oriel College. Before coming to Oxford, I received my masters in natural sciences from Cambridge, where my thesis focused on optimizing the computation of dynamical perturbations in large-scale dark matter perturbation theory. This work was completed with Dr. Zvonimir Vlah and Professor Anthony Challinor.
You can check out my work as well as a gallery of my favourite plots on my website: https://chousti.github.io