학술논문
Spectroscopic Confirmation of CEERS NIRCam-selected Galaxies at $\boldsymbol{z \simeq 8-10}$
Document Type
Working Paper
Author
Haro, Pablo Arrabal; Dickinson, Mark; Finkelstein, Steven L.; Fujimoto, Seiji; Fernández, Vital; Kartaltepe, Jeyhan S.; Jung, Intae; Cole, Justin W.; Burgarella, Denis; Chworowsky, Katherine; Hutchison, Taylor A.; Morales, Alexa M.; Papovich, Casey; Simons, Raymond C.; Amorín, Ricardo O.; Backhaus, Bren E.; Bagley, Micaela B.; Bisigello, Laura; Calabrò, Antonello; Castellano, Marco; Cleri, Nikko J.; Davé, Romeel; Dekel, Avishai; Ferguson, Henry C.; Fontana, Adriano; Gawiser, Eric; Giavalisco, Mauro; Harish, Santosh; Hathi, Nimish P.; Hirschmann, Michaela; Holwerda, Benne W.; Huertas-Company, Marc; Koekemoer, Anton M.; Larson, Rebecca L.; Lucas, Ray A.; Mobasher, Bahram; Pérez-González, Pablo G.; Pirzkal, Nor; Rose, Caitlin; Santini, Paola; Trump, Jonathan R.; de la Vega, Alexander; Wang, Xin; Weiner, Benjamin J.; Wilkins, Stephen M.; Yang, Guang; Yung, L. Y. Aaron; Zavala, Jorge A.
Source
Astrophys. J. Lett. 951, L22 (2023)
Subject
Language
Abstract
We present JWST/NIRSpec prism spectroscopy of seven galaxies selected from the Cosmic Evolution Early Release Science Survey (CEERS) NIRCam imaging with photometric redshifts z_phot>8. We measure emission line redshifts of z=7.65 and 8.64 for two galaxies, and z=9.77(+0.37,-0.29) and 10.01(+0.14,-0.19) for two others via the detection of continuum breaks consistent with Lyman-alpha opacity from a mostly neutral intergalactic medium. The presence (absense) of strong breaks (strong emission lines) give high confidence that these two galaxies are at z>9.6, but the break-derived redshifts have large uncertainties given the low spectral resolution and relatively low signal-to-noise of the CEERS NIRSpec prism data. The two z~10 sources are relatively luminous (M_UV<-20), with blue continua (-2.38 candidates with CEERS NIRSpec spectroscopy do not have secure redshifts, but the absence of emission lines in their spectra is consistent with redshifts z>9.6. We find that z>8 photometric redshifts are generally in agreement (within uncertainties) with the spectroscopic values. However, the photometric redshifts tend to be slightly overestimated (average Delta(z)=0.50+/-0.12), suggesting that current templates do not fully describe the spectra of very high-z sources. Overall, our results solidifies photometric evidence for a high space density of bright galaxies at z>8 compared to theoretical model predictions, and further disfavors an accelerated decline in the integrated UV luminosity density at z>8.
Comment: Published in ApJL. 19 pages, 9 figures, 7 tables. File with Table 6 included in source .tar file
Comment: Published in ApJL. 19 pages, 9 figures, 7 tables. File with Table 6 included in source .tar file