论文标题
$ z \ gtrsim的星系形态9 $由JWST/NIRCAM成像发现：宇宙尺寸的演变和对$ z \ sim 12 $的非常紧凑的明亮星系的识别
Morphologies of Galaxies at $z \gtrsim 9$ Uncovered by JWST/NIRCam Imaging: Cosmic Size Evolution and an Identification of an Extremely Compact Bright Galaxy at $z\sim 12$
论文作者
论文摘要
我们以$ z \ gtrsim的形态介绍了星系的形态9 $由jwst/nircam $ 2 $ - $5μ$ m成像。我们的样本包括$ 22 $的Galaxy候选人，这些候选者通过严格的辍学和玻璃，Ceors，SMACS J0723和Stephan's五重侧侧翼田地的标准确定，其中一个是$ z = 11.44 $的光谱识别。我们以$ 6 $的明亮星系为单独的$ 6 $明亮的星系，单独使用S/N $ = 10 $ - $ 40 $进行表面亮度（SB）配置文件，用于单独使用的堆叠的微弱星系，具有nircam真实数据的安全点传播功能（PSF），通过Monte-Carlo Simulations仔细评估Sytemics。我们将我们的结果与以前的JWST研究的结果进行了比较，并确认我们测量的有效半径$ r _ {\ rm e} $与以前的测量值$ z \ sim 9 $一致。我们获得了$ r _ {\ rm e} \ simeq 200 $ - $ 300 $ PC，带有类似指数的配置文件，$ n \ simeq 1 $ - $ 1.5 $的sérsic索引，$ z \ s \ sim 12 $ - $ 16 $，表示为$ r _ prepto \ rm e} \ rm e} sim \ rm e} sim \ rm rm e} sime（ $ s = -1.22^{+0.17} _ { - 0.16} $解释了$ z \ sim 0 $ - $ 16 $的宇宙进化，$ \ sim l^*_ {z = 3} $ galaxies。一个明亮的（$ m _ {\ rm uv} = - 21 $ mag）$ z \ sim 12 $，gl-z12-1，具有非常紧凑的配置文件，带有$ r _ {\ rm e} = 39 \ pm 11 $ PC，肯定扩展了PSF。即使在GL-Z12-1 SB符合AGN $+$ GALAXY复合配置文件的情况下，最佳拟合的星系组件再次紧凑，$ r _ {\ rm e} = 48^{+38} _ { - 15} $ PC（$ r r r ym ym ym ym ym ym ym ym ym ym ym）与数值模拟相比，我们发现这种紧凑的星系在$ z \ gtrsim 10 $中自然形成，并且在早期时期的频繁合并产生了$ r _ {\ rm e} \ propto（1+z）^s $的关系之后产生更多扩展的星系。
We present morphologies of galaxies at $z \gtrsim 9$ resolved by JWST/NIRCam $2$-$5μ$m imaging. Our sample consists of $22$ galaxy candidates identified by stringent dropout and photo-$z$ criteria in GLASS, CEERS, SMACS J0723, and Stephan's Quintet flanking fields, one of which has been spectroscopically identified at $z=11.44$. We perform surface brightness (SB) profile fitting with GALFIT for $6$ bright galaxies with S/N $=10$-$40$ on an individual basis and for stacked faint galaxies with secure point-spread functions (PSFs) of the NIRCam real data, carefully evaluating systematics by Monte-Carlo simulations. We compare our results with those of previous JWST studies, and confirm that effective radii $r_{\rm e}$ of our measurements are consistent with those of previous measurements at $z\sim 9$. We obtain $r_{\rm e}\simeq 200$-$300$ pc with the exponential-like profiles, Sérsic indexes of $n\simeq 1$-$1.5$, for galaxies at $z\sim 12$-$16$, indicating that the relation of $r_{\rm e}\propto (1+z)^s$ for $s=-1.22^{+0.17}_{-0.16}$ explains cosmic evolution over $z\sim 0$-$16$ for $\sim L^*_{z=3}$ galaxies. One bright ($M_{\rm UV}=-21$ mag) galaxy at $z\sim 12$, GL-z12-1, has an extremely compact profile with $r_{\rm e}=39 \pm 11$ pc that is surely extended over the PSF. Even in the case that the GL-z12-1 SB is fit by AGN$+$galaxy composite profiles, the best-fit galaxy component is again compact, $r_{\rm e}=48^{+38}_{-15}$ pc that is significantly ($>5σ$) smaller than the typical $r_{\rm e}$ value at $z\sim 12$. Comparing with numerical simulations, we find that such a compact galaxy naturally forms at $z\gtrsim 10$, and that frequent mergers at the early epoch produce more extended galaxies following the $r_{\rm e}\propto (1+z)^s$ relation.
