CEERS: Diversity of Lyman-Alpha Emitters during the Epoch of Reionization

Understand

We analyze rest-frame ultraviolet to optical spectra of three $z\simeq7.47$ - $7.75$ galaxies whose Ly$\alpha$-emission lines were previously detected with Keck/MOSFIRE observations, using the JWST/NIRSpec observations from the Cosmic Evolution Early Release Science (CEERS) survey.

• From NIRSpec data, we confirm the systemic redshifts of these Ly$\alpha$ emitters, and emission-line ratio diagnostics indicate these galaxies were highly ionized and metal poor.
• We investigate Ly$\alpha$ line properties, including the line flux, velocity offset, and spatial extension.
• For the one galaxy where we have both NIRSpec and MOSFIRE measurements, we find a significant offset in their flux measurements ($\sim5\times$ greater in MOSFIRE) and a marginal difference in the velocity shifts.