August 28 Wed 14:30-15:30
ALMA-J Seminar
hybrid; Room 102 in ALMA Building and Zoom
詳細は下記からご覧ください。
=============== August 28 Wed===============
Seminar: ALMA-J Seminar
Date and time: August 28th, 2024 (Wed.), 14:30-15:30 JST
Place: ALMA Building Room 102 / Zoom (hybrid)
Speaker : BORIS S. KALITA (Joint-Kavli Astrophysics Fellow – Kavli-IPMU, Japan | KIAA, China)
Title : The formation and influence of star-forming clumps in high redshift galaxies
Clumps have been found to dominate star formation in gas-rich (z > 1) galaxies,
thereby driving their overall evolution. I will discuss recent results from a
collection of works on this topic, that utilize public data from the James Webb
Space Telescope (JWST) and the Atacama Large Millimeter Array (ALMA) to understand
the role of clumps in galaxy evolution during the latter phase of the Cosmic
Noon (z = 1 – 2).
- Clumps can now be detected and studied across rest-frame UV to near-IR wavelengths.
Therefore, we conduct a stellar-mass tracing morphological analysis of the host galaxies. - We observe a clear evolution of galaxies from being clumpy to bulge-dominated,
revealing how galaxy morphologies and their substructures evolve over cosmic time. - We estimate a clump mass-size relation along with a stellar mass function,
finding them to match the theoretical expectations for clumps forming due to
instability-driven coherent collapse. Thus, we observationally verify the disk
instability formation scenario even for the most massive of these structures. - Our measurements (and predictions) are consistent with the properties of clumps
in z > 1 lensed systems, bridging the long-standing gap between lensed and unlensed
studies. Thus, we build a coherent picture of clump formation across various
observational scales. - We establish the clear coexistence of spiral arms and star-forming clumps,
which is important for understanding the dynamical stability of the gaseous and
stellar components of galaxies.
Organizers : Kshitiz Mallick, Yuichi Matsuda