Oral Presentation
Bursty star formation and galaxy-galaxy interactions in low-mass high-z galaxies in the era of JWST
Presenter: Yoshihisa Asada (Kyoto Univ.)
Revealing the assembly process of low-mass high-z galaxies has been a longstanding goal of modern extragalactic astronomy. In the hierarchical picture of structure formation, galaxy interactions and mergers are thought to be frequent in the early universe and essential for the evolution of these galaxies. Early results from JWST observations suggested the evolution sequence of high-z galaxies is highly bursty – fluctuating star formation with very short timescales – and galaxy local environments such as interactions can be a cause of the bursty star formation. We will present our results investigating the star formation burstiness and the local environments of low-mass galaxies at z~5-6. We used JWST observations of gravitational lensing cluster fields by the CAnadian NIRISS Unbiased Cluster Survey (CANUCS), to explore low-mass galaxies at high-z in various environments. We found the galaxy-galaxy interaction seems to be a quite common phenomenon among high-z low-mass galaxies, and the clustered environments or galaxy-galaxy interactions indeed enhance the star formation burstiness in low-mass high-z galaxies, by enabling rapid bursts of star formation and subsequent fast quenching. Our results suggest the galaxy local environment is quite pivotal in early-phase galaxy assembly. In the talk we will also show results from NIRSpec follow-up observations to further discuss the physical origins triggering bursty star formations in low-mass interacting galaxies at high-z.
asiaa.sinica.edu.tw