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Arxiv: A JWST investigation into the bar fraction at redshifts 1 < z < 3 Published: 9/18/2023 9:00:04 PM Updated: 4/23/2024 8:37:45 PM

Paper abstract: The presence of a stellar bar in a disc galaxy indicates that the galaxyhosts in its main part a dynamically settled disc and that bar-driven processesare taking place in shaping its evolution. Studying the cosmic evolution of thebar fraction in disc galaxies is therefore essential to understand galaxyevolution in general. Previous studies have found, using the Hubble SpaceTelescope (HST), that the bar fraction significantly declines from the localUniverse to redshifts near one. Using the first four pointings from the JamesWebb Space Telescope (JWST) Cosmic Evolution Early Release Science Survey(CEERS) and the initial public observations for the Public Release Imaging forExtragalactic Research (PRIMER), we extend the studies of the bar fraction indisc galaxies to redshifts 1 <= z <= 3, i.e., for the first time beyondredshift two. We only use galaxies that are also present in the Cosmic AssemblyNear-IR Deep Extragalactic Legacy Survey (CANDELS) on the Extended Groth Strip(EGS) and Ultra Deep Survey (UDS) HST observations. An optimised sample of 368close-to-face-on galaxies is visually classified to find the fraction of barsin disc galaxies in two redshift bins: 1 <= z <= 2 and 2 < z <= 3.The bar fraction decreases from ~ 17.8^{+ 5.1}_{- 4.8} per cent to~ 13.8^{+ 6.5}_{- 5.8} per cent (from the lower to the higher redshiftbin), but is about twice the bar fraction found using bluer HST filters. Ourresults show that bar-driven evolution might commence at early cosmic times andthat dynamically settled discs are already present at a lookback time of ~11 Gyrs.