Abstract
High-redshift galaxies at cosmic noon (z ~ 1-3) frequently display irregular, clumpy morphologies distinct from the smooth disks observed in the local universe. Despite decades of studies, there are a wide variety of observational and theoretical approaches, making direct comparisons across studies difficult. This study aims to develop and apply a physically motivated method for characterizing clump formation using JWST NIRCam F200W imaging from the Cosmic Evolution Early Release Science (CEERS) Survey. For a sample of 24 galaxies across $0.83 \leq z \leq 3.1$, the Toomre stability parameter $Q$ and turbulent Jeans mass $M_J$ were calculated using star formation rate surface densities derived from the Kennicutt-Schmidt law, effective radii from GALFIT S\'{e}rsic profile fitting, and empirically estimated velocity dispersions. Both star formation rate surface density and gas surface density increased systematically with redshift, consistent with higher gas fractions at earlier cosmic times. Galaxies in the low-stability bin ($Q = 1-20$) showed a median gas surface density of $17.6~M_{\odot}~\mathrm{pc}^{-2}$ and a median turbulent Jeans mass of $2.95 \times 10^{9}~M_{\odot}$, consistent with the observed mass range of giant star-forming clumps, while more stabilized systems showed an increase in $M_J$ by a factor of ${\sim}2.6$ and a decline in star formation rate surface density by three orders of magnitude. Morphological comparison of galaxies across stability bins using JWST imaging provided direct visual confirmation of these trends. These results demonstrate that observable galaxy properties combined with disk instability theory provide a reproducible, physically grounded framework for quantifying clump formation in high-redshift star-forming disks.
Advisor
DeGroot, Laura
Department
Physics
Recommended Citation
Gomes, Anthony R., "Quantifying Clumpy Galaxies: Inferring Turbulent Jeans Mass from Galaxy Imaging" (2026). Senior Independent Study Theses. Paper 13559.
https://openworks.wooster.edu/independentstudy/13559
Disciplines
External Galaxies | Other Astrophysics and Astronomy | Physical Processes
Keywords
Clumpy Galaxy, Disk Stability, Python, Astropy, Fragmentation, Redshift, Velocity Dispersion, Photutils, Galaxy Morphology, Clumpy Galaxies, JWST, NIRcam, GALFIT, Jeans mass, star formation rate, gas surface density, Toomre Q, galaxies, Sersic index
Publication Date
2026
Degree Granted
Bachelor of Arts
Document Type
Senior Independent Study Thesis
© Copyright 2026 Anthony R. Gomes