Hi, I'm Ahmad - I'm a postdoc in astrophysics at the University of Cologne, working in Steffi Walch-Gassner's group. Previously, I was a postdoc at the University of Exeter working with Clare Dobbs. I did my PhD with Tim Harries, also at Exeter.
My research
I study star formation, specifically how massive stars (>20 solar masses) influence their birth environments through stellar feedback. This includes radiative feedback (photoionization, radiation pressure) and mechanical feedback (stellar winds, supernovae). Some of the questions I am interested in are:
- how do feedback processes expel gas from stellar clusters?
- how are star formation rates altered by heating, dispersing, or compressing gas reservoirs?
- which processes dominate in which regimes?
- how do the intense radiation fields affect the evolution of protoplanetary discs via photoevaporation?
- how does all this vary with galactic environment?
Methods
I simulate stellar feedback in Giant Molecular Clouds using computational hydrodynamics and radiative transfer:
- I use Monte Carlo radiative transfer on a grid to apply high-accuracy radiative feedback in isolated cloud models. This calculates ionized gas temperatures and radiation pressures for different gas/dust compositions.
- I carry out galaxy zoom-ins using smoothed particle hydrodynamics and ray tracing. This includes galaxy-scale dynamics and self-consistent interactions between clouds.