EMPRESS。III。极贫金属半导体（EMPGs）的形态、恒星星族和动力学：EMPGs是高- $z$年轻半导体的局部类似物吗？
EMPRESS. III. Morphology, Stellar Population, and Dynamics of Extremely Metal Poor Galaxies (EMPGs): Are EMPGs Local Analogs of High-$z$ Young Galaxies?
摘要：
本文给出了27个金属丰度为0.01- 0.1 Z $z\sim0$的极端贫金属星系（EMPG）的形态和恒星星族。我们使用{ \sc Galfit}软件对EMPG的深Subaru/HSC $i$波段图像进行多分量表面亮度（SB）轮廓拟合，仔细去除尾部的SB贡献。我们发现，中等恒星质量为$\log(M_{*}/{\rm M}_{\odot})=6.0$的EMPG具有中等的S{é}rsic指数$n=1.1$和中等的有效半径$r_{\rm e}=200$ pc，这表明典型的EMPG具有非常致密的盘.我们比较了EMPG与$z\sim6$星系和本星系的尺寸-质量（$r_{\rm e}$ - $M_*$）图，发现大多数EMPG具有类似于$z\sim0$的$r_{\rm e}$ - $M_*$关系，而不是$z\sim6$星系。在$r_{\rm e}$ - $M_*$关系中，并不是每个EMPG都是高$z$年轻星系的局部类似物.一对EMPG和尾巴的频谱，到目前为止，表明尾巴是动态相关的EMPG的中值速度差为$ΔV=101\pm32$公里秒$^{-1}$。这个中等大小的$ΔV$不能用尾部的动力学来解释，但很可能是尾部的坠落。这是第一次，我们可以识别出正在落入尾部的贫金属恒星形成系统。
英文摘要：
We present the morphology and stellar population of 27 extremely metal poor galaxies (EMPGs) at $z\sim0$ with metallicities of 0.01--0.1 Z$_{\odot}$. We conduct multi-component surface brightness (SB) profile fitting for the deep Subaru/HSC $i$-band images of the EMPGs with the {\sc Galfit} software, carefully removing the SB contributions of tails. We find that the EMPGs with a median stellar mass of $\log(M_{*}/{\rm M}_{\odot})=6.0$ have a median S{é}rsic index of $n=1.1$ and a median effective radius of $r_{\rm e}=200$ pc, suggesting that typical EMPGs have very compact disk. We compare the EMPGs with $z\sim6$ galaxies and local galaxies on the size-mass ($r_{\rm e}$-$M_*$) diagram, and identify that the majority of the EMPGs have a $r_{\rm e}$-$M_*$ relation similar to $z\sim0$ star-forming galaxies rather than $z\sim6$ galaxies. Not every EMPG is a local analog of high-$z$ young galaxies in the $r_{\rm e}$-$M_*$ relation. A spectrum of one pair of EMPG and tail, so far available, indicates that the tail is dynamically related to the EMPG with a median velocity difference of $ΔV=101\pm32$ km s$^{-1}$. This moderately-large $ΔV$ cannot be explained by the dynamics of the tail, but likely by the infall on the tail. For the first time, we may identify the metal-poor star-forming system just now infalling into the tail.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
