The physics of giant star-forming regions in primordial galaxies from a synergy of observations and simulations.
The morphology of star forming galaxies in the distant Universe at redshift z=1-3, is remarkably different from that of nearby spirals. They have irregular morphologies, often dominated by giant star forming regions dubbed « giant clumps ». This is thought to be driven by their very large gas fractions and strong turbulence: gas-rich galaxies can become violently unstable and fragment in such giant clumps.
However, a quantitative understanding of the nature and physical properties of these clumps is still lacking Hotly debated topics of contending remain, regarding the distribution of clumps masses, star formation rates, sizes, clumps formation rates and lifetime. It also remains unknown whether they survive stellar feedback processes, in which case they can drive the growth of galactic bulges and the fueling of supermassive black holes at the center of galaxies.
We propose a PhD project to explore a state of the art approach to this topic, tracking 3 complementary lines of research on:
1) the physical characterization of clumps properties from observations,
2) systematic and quantitative comparison of observations to simulations,
3) running suites of very high resolution numerical simulations with an improved modeling of star formation and feedback.
These complementary lines will bring a robust understanding of the nature of the giant clumps and their role in shaping disks, bulges and central black holes. They will also provide a new way to constrain the gas fraction in galaxies at various epochs, which is another highly debated issue in galaxy formation. The proposed work will ideally prepare future developments with the use of JWST, and comparison to forthcoming ALMA data. The proposed thesis will also employ numerical simulations performed on the largest supercomputers in France and Europe.
This is a funded PhD project with F. Bournaud & E. Daddi at CEA-Saclay. Candidats should send their applications and CV to firstname.lastname@example.org and email@example.com. Applications received until March 1st will be given full consideration, and later appplications will be considered until the position is filled.