Projects | ASGARD Group

We offer Bachelor and Master thesis projects in theoretical and computational astrophysics. Typical topics include — but are not limited to — magnetohydrodynamics (MHD), radiative transfer (RT), numerical methods and simulations, and data analysis / observational comparisons.

This page is under construction. If you are interested in a thesis project, please get in touch via the contact page or email max.gronke@uni-heidelberg.de and tell us about your interests and background.

Cold Gas Survival in Galactic Winds

This project investigates the conditions under which cold gas clouds can persist while being entrained in galactic winds, focusing on the interplay between turbulent mixing and radiative cooling. By extending previous studies beyond the narrow parameter regimes explored so far, it aims to map out the full landscape of cold-gas survival in realistic outflow conditions.

Lyman-alpha as a proxy for ionizing photon escape

How ionizing photons escaped the dense neutral hydrogen envelopes of galaxies to reionize the Universe is unknown. This project aims to investiate the issue using Lyman-alpha radiative transfer simulations and a comparison with data.

Lyman-alpha pumping during the dark ages

This project uses Ly𝛼 radiative-transfer simulations of galaxies and their environments to quantify Wouthuysen–Field coupling and derive sub-grid prescriptions for large-scale 21 cm/EoR simulations. The aim is to bridge the vast scale gap—from sub-pc Ly𝛼 scattering to Mpc-scale reionization structures—so upcoming 21 cm experiments can model this effect accurately.

Modeling gas clouds in the vicinity of a black hole

This project studies how gas clouds orbiting the Galactic Centre evolve under strong tidal forces, fragmentation, and radiative cooling. By performing hydrodynamical simulations that include gravitational fragmentation and cooling-driven condensation, it aims to understand the conditions under which such clouds survive or dissipate.

Radiation Pressure–Driven Acceleration and Survival of Cold Gas

This project explores how radiation pressure accelerates cold gas and determines the conditions under which such gas can withstand shear forces and remain intact. Using radiation–hydrodynamic simulations, it aims to clarify when radiation pressure aids entrainment versus when it leads to cloud disruption.

Stability of Cold Streams in the Circumgalactic Medium

This project investigates the survival of cold, filamentary streams feeding galaxies at high redshift by comparing their properties in cosmological simulations with existing analytical and small-scale stability criteria. The aim is to test how well theoretical predictions hold under realistic CGM conditions.

The effect of spectral stacking on the information content

This project investigates how stacking resonant-line spectra (e.g. Lyα, Mg II) alters their spectral shape and information content, a key question for interpreting faint circumgalactic emission. By combining radiative-transfer simulations, synthetic spectra, and a dedicated stacking and fitting pipeline, the project will systematically compare the constraints achievable from individual spectra versus stacks.

Thermal Instability and Heating Mechanisms in Stratified Atmospheres

This project investigates how different, more realistic forms of heating regulate thermal instability in stratified atmospheres such as the intracluster medium, moving beyond the highly idealized ‘magic heating’ used in previous studies. Combining theoretical analysis with numerical simulations, it aims to clarify when and how cold gas can condense out of a hot, gravitationally stratified plasma.

Thermal Instability in Turbulent Multiphase Media

This project examines how and where thermal instability develops within turbulent flows in the ISM, CGM, and ICM by identifying the conditions under which compressed regions cool and condense. Using turbulent-box simulations that track the evolution of individual gas parcels, it aims to map out the pathways through which turbulence drives multiphase structure.