UNCOVER: A NIRSpec Census of Lensed Galaxies at z=8.50-13.08 Probing a High AGN Fraction and Ionized Bubbles in the Shadow

Understand

We present JWST NIRSpec prism spectroscopy of gravitationally lensed galaxies at $z\gtrsim9$ found behind the massive galaxy cluster Abell 2744 in the UNCOVER Cycle 1 Treasury Program.

• We confirm the source redshift via emission lines and/or the Ly$\alpha$ break feature for ten galaxies at z=8.50-13.08 down to $M_{\rm UV}=-17.3$.
• We achieve a high confirmation rate of 100\% for $z>9$ candidates reported in Atek et al.
• (2023).