Unveiling Luminous Ly Emitters at z 6 through JWST/NIRCam Imaging in the COSMOS Field

We study a sample of 14 spectroscopically confirmed Ly alpha Emitters (LAEs) in the late era of reionization (at redshift z approximate to 6) based on the JWST/NIRCam imaging dataset. These LAEs with high Ly alpha luminosity of L(Ly alpha) similar to 10(42.4)-10(43.4) erg s(-1) have been covered by the (ongoing) COSMOS-Web survey (Kartaltepe et al., 2021; Casey et al., 2023) over 0.28 deg(2) in four NIRCam bands (F115W, F150W, F277W, and F444W). With JWST/NIRCam imaging, we determine the M-UV continua with UV ranging from -20.5 to -18.5 mag. The UV slopes have a median value of beta approximate to-2.35, and the steepest slopes can reach beta <-3. Under an excellent spatial resolution of JWST, we identify three out of the sample as potential merging/interacting systems. The 14 LAEs (and their components) are compact in morphology residing substantially below the mass-size relation of high-z galaxies. We further investigate their physical properties including the stellar mass (M-*) and star-formation rates (SFRs). Most of the LAEs lie on the SFR-M-* main-sequence relation while two of them featured as "little red dots" likely host active galactic nuclei (AGN), implying a similar to 10% AGN fraction. Moreover, we reveal that a new correlation may exist between Ly alpha equivalent width and the offset between Ly alpha and UV emission (Delta d(Ly alpha)) with a median Delta d(Ly alpha)similar to 1 kpc. This could be explained by Ly alpha radiative transfer process in both ISM and CGM. The results usher a new era of detailed analysis on high-z LAEs with the JWST capability.