High-Redshift Galaxy Candidates at $z = 9-10$ as Revealed by JWST Observations of WHL0137-08

Understand

We report the discovery of four galaxy candidates observed 450 - 600 Myr after the Big Bang with photometric redshifts between z ~ 8.3 - 10.2 measured using the JWST NIRCam imaging of the galaxy cluster WHL0137-08 observed in 8 filters spanning 0.8-5.0 micron, plus 9 Hubble filters spanning 0.4-1.7 micron.

• One candidate is gravitationally lensed with a magnification of ~8, while the other three are located in a nearby NIRCam module with expected magnifications of <~ 1.1.
• Using SED fitting, we estimate the stellar masses of these galaxies are typically in the range log M*/Msun = 8.3 - 8.7.
• All appear young with mass-weighted ages < 240 Myr, low dust content A_V < 0.15 mag, and specific star formation rates sSFR ~0.25 - 10 /Gyr for most.