We present the results of a systematic study of the rest-frame optical
morphology of quiescent galaxies at zβ₯3 using the Near-Infrared Camera
(NIRCam) onboard JWST. Based on a sample selected by UVJ color or NUVUVJ
color, we focus on 26 quiescent galaxies with
9.8<log(Mββ/Mββ)<11.4 at 2.8<zphotβ<4.6 with publicly
available JWST data. Their sizes are constrained by fitting the S\'ersic
profile to all available NIRCam images. We see a negative correlation between
the observed wavelength and the size in our sample and derive their size at the
rest-frame 0.5ΞΌm taking into account this trend. Our quiescent
galaxies show a significant correlation between the rest-frame 0.5ΞΌm size and the stellar mass at zβ₯3. The analytical fit for them at
log(Mββ/Mββ)>10.3 implies that our size - stellar mass relations
are below those at lower redshifts, with the amplitude of βΌ0.6kpc
at Mββ=5Γ1010Mββ. This value agrees with the
extrapolation from the size evolution of quiescent galaxies at z<3 in the
literature, implying that the size of quiescent galaxies increases
monotonically from zβΌ3β5. Our sample is mainly composed of galaxies with
bulge-like structures according to their median S\'ersic index and axis ratio
of nβΌ3β4 and qβΌ0.6β0.8, respectively. On the other hand, there is a
trend of increasing fraction of galaxies with low S\'ersic index, suggesting
3<z<5 might be the epoch of onset of morphological transformation with a
fraction of very notable disky quenched galaxies.Comment: 23 pages, 16 figures, 2 tables; submitted to Ap