# Spectroscopic confirmation of CEERS NIRCam-selected galaxies at $\boldsymbol{z \simeq 8-10}$

**Authors:** Pablo Arrabal Haro, Mark Dickinson, Steven L. Finkelstein, Seiji Fujimoto, Vital Fernández, Jeyhan S. Kartaltepe, Intae Jung, Justin W. Cole, Denis Burgarella, Katherine Chworowsky, Taylor A. Hutchison, Alexa M. Morales, Casey Papovich, Raymond C. Simons, Ricardo O. Amorín, Bren E. Backhaus, Micaela B. Bagley, Laura Bisigello, Antonello Calabrò, Marco Castellano  
**arXiv:** [2304.05378](https://arxiv.org/abs/2304.05378)  
**Date:** 2023-04-11  
**Summary page:** https://www.summarizepaper.com/en/paper/2304.05378v1/

## Key points

- Study presents results of JWST/NIRSpec prism spectroscopy of seven galaxies from CEERS NIRCam imaging with z_phot>8
- Two at z=7.65 and 8.64
- Two at z=9.77(+0.37,-0.29) and 10.01(+0.14,-0.19)
- Redshift measurements derived from detection of continuum breaks consistent with Lyman-alpha opacity from neutral intergalactic medium
- Strong breaks or emission lines in spectra indicate high confidence that two galaxies are located at redshifts >9.6
- Two sources at approximately z~10 found to be relatively luminous (M_UV<-20), with blue continua (-2.3<beta<-1.9) and low dust attenuation (A_V=0.15(+0.3,-0.1))

## Summary

This study presents the results of 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. The authors measure emission line redshifts for four galaxies, with two galaxies at z=7.65 and 8.64, and two others at z=9.77(+0.37,-0.29) and 10.01(+0.14,-0.19). These redshift measurements are derived from the detection of continuum breaks consistent with Lyman-alpha opacity from a mostly neutral intergalactic medium. The presence or absence of strong breaks or strong emission lines in the spectra provides high confidence that these two galaxies are located at redshifts greater than 9.6. The two sources at approximately z~10 are found to be relatively luminous (M_UV<-20), with blue continua (-2.3<beta<-1.9) and low dust attenuation (A_V=0.15(+0.3,-0.1)).