ALMA FIR View of Ultra-high-redshift Galaxy Candidates at z 11-17: Blue Monsters or Low-z Red Interlopers? Academic Article uri icon

abstract

  • Abstract We present Atacama Large Millimeter/submillimeter Array (ALMA) Band 7 observations of a remarkably bright galaxy candidate at z phot = 16.7 0.3 + 1.9 (M UV = 21.6), S5-z17-1, identified in James Webb Space Telescope (JWST) Early Release Observation data of Stephens Quintet. We do not detect the dust continuum at 866 m, ruling out the possibility that S5-z17-1 is a low-z dusty starburst with a star formation rate of 30 M yr1. We detect a 5.1 line feature at 338.726 0.007 GHz exactly coinciding with the JWST source position, with a 2% likelihood of the signal being spurious. The most likely line identification would be [O iii]52 m at z = 16.01 or [C ii]158 m at z = 4.61, whose line luminosities do not violate the nondetection of the dust continuum in both cases. Together with three other z 1113 candidate galaxies recently observed with ALMA, we conduct a joint ALMA and JWST spectral energy distribution (SED) analysis and find that the high-z solution at z 1117 is favored in every candidate as a very blue (UV continuum slope of 2.3) and luminous (M UV [ 24:21]) system. Still, we find in several candidates that reasonable SED fits ( 2 4) are reproduced by type II quasar and/or quiescent galaxy templates with strong emission lines at z 35, where such populations predicted from their luminosity functions and EW([O iii]+H) distributions are abundant in survey volumes used for the identification of the z 1117 candidates. While these recent ALMA observation results have strengthened the likelihood of the high-z solutions, lower-z possibilities are not completely ruled out in several of the z 1117 candidates, indicating the need to consider the relative surface densities of the lower-z contaminants in the ultra-high-z galaxy search.

published proceedings

  • ASTROPHYSICAL JOURNAL

author list (cited authors)

  • Fujimoto, S., Finkelstein, S. L., Burgarella, D., Carilli, C. L., Buat, V., Casey, C. M., ... Yung, L.

complete list of authors

  • Fujimoto, Seiji||Finkelstein, Steven L||Burgarella, Denis||Carilli, Chris L||Buat, Veronique||Casey, Caitlin M||Ciesla, Laure||Tacchella, Sandro||Zavala, Jorge A||Brammer, Gabriel||Fudamoto, Yoshinobu||Ouchi, Masami||Valentino, Francesco||Cooper, MC||Dickinson, Mark||Franco, Maximilien||Giavalisco, Mauro||Hutchison, Taylor A||Kartaltepe, Jeyhan S||Koekemoer, Anton M||Kojima, Takashi||Larson, Rebecca L||Murphy, EJ||Papovich, Casey||Perez-Gonzalez, Pablo G||Somerville, Rachel S||Yoon, Ilsang||Wilkins, Stephen M||Akins, Hollis||Amorin, Ricardo O||Haro, Pablo Arrabal||Bagley, Micaela B||Chworowsky, Katherine||Cleri, Nikko J||Cooper, Olivia R||Costantin, Luca||Daddi, Emanuele||Ferguson, Henry C||Grogin, Norman A||Jimenez-Andrade, EF||Juneau, Stephanie||Kirkpatrick, Allison||Kocevski, Dale D||Le Bail, Aurelien||Long, Arianna||Lucas, Ray A||Magnelli, Benjamin||McKinney, Jed||Rose, Caitlin||Seille, Lise-Marie||Simons, Raymond C||Weiner, Benjamin J||Yung, LY Aaron

publication date

  • October 2023