Paper: A Long Time Ago in a Galaxy Far, Far Away: A Candidate z ∼ 12 Galaxy in Early JWST CEERS Imaging
Authors: Steven L. Finkelstein, Micaela B. Bagley, Pablo Arrabal Haro, Mark Dickinson, Henry C. Ferguson, Jeyhan S. Kartaltepe, Casey Papovich, Denis Burgarella, Dale D. Kocevski, Marc Huertas-Company, Kartheik G. Iyer, Anton M. Koekemoer, Rebecca L. Larson, Pablo G. Pérez-González, Caitlin Rose, Sandro Tacchella, Stephen M. Wilkins, Katherine Chworowsky, Aubrey Medrano, Alexa M. Morales, Rachel S. Somerville, L. Y. Aaron Yung, Adriano Fontana, Mauro Giavalisco, Andrea Grazian, Norman A. Grogin, Lisa J. Kewley, Allison Kirkpatrick, Peter Kurczynski, Jennifer M. Lotz, Laura Pentericci, Nor Pirzkal, Swara Ravindranath, Russell E. Ryan, Jonathan R. Trump, Guang Yang, Omar Almaini, Ricardo O. Amorín, Marianna Annunziatella, Bren E. Backhaus, Guillermo Barro, Peter Behroozi, Eric F. Bell, Rachana Bhatawdekar, Laura Bisigello, Volker Bromm, Véronique Buat, Fernando Buitrago, Antonello Calabrò, Caitlin M. Casey, Marco Castellano, Óscar A. Chávez Ortiz, Laure Ciesla, Nikko J. Cleri, Seth H. Cohen, Justin W. Cole, Kevin C. Cooke, M. C. Cooper, Asantha R. Cooray, Luca Costantin, Isabella G. Cox, Darren Croton, Emanuele Daddi, Romeel Davé, Alexander de la Vega, Avishai Dekel, David Elbaz, Vicente Estrada-Carpenter, Sandra M. Faber, Vital Fernández, Keely D. Finkelstein, Jonathan Freundlich, Seiji Fujimoto, Ángela García-Argumánez, Jonathan P. Gardner, Eric Gawiser, Carlos Gómez-Guijarro, Yuchen Guo, Kurt Hamblin, Timothy S. Hamilton, Nimish P. Hathi, Benne W. Holwerda, Michaela Hirschmann, Taylor A. Hutchison, Anne E. Jaskot, Saurabh W. Jha, Shardha Jogee, Stéphanie Juneau, Intae Jung, Susan A. Kassin, Aurélien Le Bail, Gene C. K. Leung, Ray A. Lucas, Benjamin Magnelli, Kameswara Bharadwaj Mantha, Jasleen Matharu, Elizabeth J. McGrath, Daniel H. McIntosh, Emiliano Merlin, Bahram Mobasher, Jeffrey A. Newman, David C. Nicholls, Viraj Pandya, Marc Rafelski, Kaila Ronayne, Paola Santini, Lise-Marie Seillé, Ekta A. Shah, Lu Shen, Raymond C. Simons, Gregory F. Snyder, Elizabeth R. Stanway, Amber N. Straughn, Harry I. Teplitz, Brittany N. Vanderhoof, Jesús Vega-Ferrero, Weichen Wang, Benjamin J. Weiner, Christopher N. A. Willmer, Stijn Wuyts, Jorge A. Zavala
Figure caption: (Top) 1.″8 × 1.″8 cutout images centered on the position of Maisie’s Galaxy in the non-PSF-matched images. This source exhibits the hallmark colors of a distant galaxy: no discernible flux in a dropout band (we show stacked F606W+F814W, as well as F115W images; the circle has a radius of 0.″3) and a significant detection in the bluest detection band (F200W in this case). Very faint flux is visible (at ∼2.8σ significance when measured in a 0.″2 diameter aperture) in F150W, which drives the redshift to z ∼ 12. The wide wavelength range of NIRCam allows this source to be well detected in multiple filters, and in the imaging alone, it is clear that this source exhibits a blue spectral shape. (Bottom) Same ordering as the top panel for sky-uncertainty maps constructed from the variance of the readout noise, all using a linear scale from 0.33 to 3× the robustly measured sky standard deviation in each band. The patchiness of the uncertainties is due to a loss of exposure time when cosmic rays are detected and rejected in the multiple readouts or in outlier rejection when combining the dithered exposures (the 2× larger original pixel scale of the LW channels results in larger patches than the SW channels). The uncertainty arrays show no excess in rejected pixels near the candidate galaxy.