Résumé / Abstract Journal-club_Galaxies

Séminaire/Seminar Galaxies

« Resolving star formation processes at 10-100s pc resolution in distant galaxies with JWST/NIRCam »

Adélaïde Claeyssens
Department of Astrononomy, Stockholm University (Stockholm, Suède)

Distant galaxies present a very irregular morphology dominated by compact sub-structures called “clumps”. The physical properties of these star-forming systems remain relatively unexplored and their role in galaxy formation and evolution is not clear. The first detections of UV-bright clumps from z=10 to z=1 indicate that these star-forming clumps could be a major mode of star formation and galaxy assembly.
However, resolving structures at 10-100s pc scales in high redshift galaxies (z>1) is hardly achievable with current telescopes even with space-based observations. Combining the unprecedented sensitivity and spatial resolution of JWST with the natural gravitational lens telescopes is the only way to reach hundred/sub-hundred pc resolutions in hundreds of galaxies, necessary to resolve individual star-forming systems and star clusters at UV-optical wavelengths. I will present the first results on resolved high redshift star formation processes obtained from JWST/NIRCam observations of strongly lensed galaxies observed in multiple galaxy cluster fields (SMACS0723, WHL0137, Abell2744). The optical restframe, probed with the JWST, enables us to measure physical properties of >2000 clumps (age, mass, extinction). We derive effective radii from <10 to 100s pc and masses ranging from 10^5 to 10^9 Msun, overlapping with massive star clusters in the local universe. Comparing these results with the most recent hydrodynamical simulations of galaxies, we can understand the physical processes involved in the formation and evolution of these clumps (such as gas turbulence, stellar feedback, galaxy mergers and bulge formation). This study show the potential of JWST observations for understanding the conditions under which galaxies assembly and evolve across the cosmic time and allow us to study for the first time the formation and the role of star clusters in rapidly evolving galaxies.
jeudi 11 janvier 2024 - 11:30
Salle des séminaires Évry Schatzman
Institut d'Astrophysique de Paris
Page web du séminaire / Seminar's webpage