论文标题
主要序列星系中心和郊区的差分组装历史，$ z \ sim2.3 $
The Differential Assembly History of the Centers and Outskirts of Main Sequence Galaxies at $z\sim2.3$
论文作者
论文摘要
我们介绍了一项针对60美元的$ z \ sim2.3 $主序列的空间分辨恒星形成历史（SFHS）的研究，该研究是从Goods-N Field中的Mosdef Spectroscopic调查中选出的星形星系，中位数质量$ \ log（M_ \ \ Star/M_ \ odot）= 9.75 $ \ odot）= 9.75 $ $ \ odot） $ 8.6 <\ log（m_ \ star/m_ \ odot）<11.5 $。使用观察到的$ z_ \ mathrm {f850lp} -h_ \ mathrm {f160w} $ colors使用观察到的$ z_ \ mathrm {f850lp} $颜色，将光度法分解为中央和外部空间组件。该探矿代码用于使用HST/ACS和WFC3，Spitzer/IRAC以及地面光度法建模中心，郊区和集成星系的光谱能量分布，并在MOSDEF光谱中对气相金属性和SpectRoscopic Redshift具有其他约束。对于低分辨率带，通过迭代方法确定空间分辨的光度法。重建后的SFHS表明，观察到大多数具有$ \ log（M_ \ star/m_ \ odot）<10.5 $的星系<10.5 $，而其中央区域经历了相对较新的（$ <100 $）的星形爆发，而郊区郊区的Quasi-Steady Sfh则可以轻轻地朝着朝着Redshift the Redshift the Redshift the sfh，而郊区的Quasi-Steady Sfh则可以增强。中央部分增强的恒星形成活性与高度耗散气体压实和积聚产生的想法大致一致。样品中观察到的各种中央密度和大小的范围表明，对于所选的星系，此类过程已经开始，但仍未完成。这意味着在宇宙中午选择星系星系通常包括在“进化”进化阶段的系统，这些系统最近开始开始一系列恒星形成活动，这些恒星形成活动可能会在接下来的数百万年内引发内而外。
We present a study of spatially-resolved star formation histories (SFHs) for 60 $z\sim2.3$ main-sequence, star-forming galaxies selected from the MOSDEF spectroscopic survey in the GOODS-N field, with median stellar mass $\log(M_\star/M_\odot)=9.75$ and spanning the range $8.6<\log(M_\star/M_\odot)<11.5$. Photometry is decomposed into a central and outer spatial component using observed $z_\mathrm{F850LP}-H_\mathrm{F160W}$ colors. The Prospector code is used to model spectral energy distributions for the center, outskirt, and integrated galaxy using HST/ACS and WFC3, Spitzer/IRAC, and ground-based photometry, with additional constraints on gas-phase metallicity and spectroscopic redshift from MOSDEF spectroscopy. For the low-resolution bands, spatially-resolved photometry is determined with an iterative approach. The reconstructed SFHs indicate that the majority of galaxies with $\log(M_\star/M_\odot)<10.5$ are observed while their central regions undergo relatively recent ($<100$ Myr) bursts of star formation, while the outskirts have a smooth, quasi-steady SFH that gently increases towards the redshift of observation. The enhanced star formation activity of the central parts is broadly consistent with the idea that it is produced by highly dissipative gas compaction and accretion. The wide range of central densities and sizes observed in the sample suggests that for the selected galaxies such a process has started but is still far from being completed. The implication would be that selecting star-forming galaxies at cosmic noon frequently includes systems in an "evolved" evolutionary phase where the centers have recently started a burst of star formation activity that will likely initiate inside-out quenching in the next several hundred million years.
