First Look at z > 1 Bars in the Rest-frame Near-infrared with JWST Early CEERS Imaging
Papovich, Casey; Finkelstein, Steven L.; Barro, Guillermo; Pérez-González, Pablo G.; Arrabal Haro, Pablo; Bagley, Micaela B.; Bell, Eric F.; Calabrò, Antonello; Cleri, Nikko J.; Costantin, Luca; Cooper, M. C.; Dickinson, Mark; Ferguson, Henry C.; Giavalisco, Mauro; Grogin, Norman A.; Hathi, Nimish P.; Holwerda, Benne W.; Hutchison, Taylor A.; Kartaltepe, Jeyhan S.; Kocevski, Dale D.; Koekemoer, Anton M.; Lucas, Ray A.; Pirzkal, Nor; Ravindranath, Swara; Trump, Jonathan R.; Yung, L. Y. Aaron; Zavala, Jorge A.; Gardner, Jonathan P.; Mobasher, Bahram; Wuyts, Stijn; Lotz, Jennifer M.; de la Vega, Alexander; McGrath, Elizabeth J.; Dekel, Avishai; Pandya, Viraj; Jogee, Shardha; Huertas-Company, Marc; Backhaus, Bren E.; Franco, Maximilien; Davis, Kelcey; Rose, Caitlin; Wang, Weichen; Guo, Yuchen; Vega-Ferrero, Jesús; Coogan, Rosemary T.; Croton, Darren; Chen, Zilei; Wise, Eden
United States, United Kingdom, Japan, Spain, France, Italy, Australia, Israel
Abstract
Stellar bars are key drivers of secular evolution in galaxies and can be effectively studied using rest-frame near-infrared (NIR) images, which trace the underlying stellar mass and are less impacted by dust and star formation than rest-frame UV or optical images. We leverage the power of JWST CEERS NIRCam images to present the first quantitative identification and characterization of stellar bars at z > 1 based on rest-frame NIR F444W images of high resolution (~1.3 kpc at z ~ 1-3). We identify stellar bars in these images using quantitative criteria based on ellipse fits. For this pilot study, we present six examples of robustly identified bars at z > 1 with spectroscopic redshifts, including the two highest-redshift bars at z ~ 2.136 and 2.312 quantitatively identified and characterized to date. The stellar bars at z ~ 1.1-2.3 presented in our study have projected semimajor axes of ~2.9-4.3 kpc and projected ellipticities of ~0.41-0.53 in the rest-frame NIR. The barred host galaxies have stellar masses ~1 × 1010 to 2 × 1011 M ⊙ and star formation rates of ~21-295 M ⊙ yr-1, and several have potential nearby companions. Our finding of bars at z ~ 1.1-2.3 demonstrates the early onset of such instabilities and supports simulations where bars form early in massive dynamically cold disks. It also suggests that if these bars at lookback times of 8-11 Gyr survive out to present epochs, bar-driven secular processes may operate over a long time and have a significant impact on some galaxies by z ~ 0.