On the UV compactness and morphologies of typical Lyman-a emitters from z~2 to z~6
Ana Paulino-Afonso, David Sobral, Bruno Ribeiro, Jorryt Matthee, Sérgio Santos, João Calhau, Alex Forshaw, Andrea Johnson, Joanna Merrick, Sara Pérez, Oliver Sheldon
We investigate the rest-frame UV morphologies of a large sample of Lyman-a emitters (LAEs) from z~2 to z~6, selected in a uniform way with 16 different narrow- and medium-bands over the full COSMOS field. We use 3045 LAEs with HST coverage in a stacking analysis and find that they have M_UV~-20, below M*_UV at these redshifts. We also focus our analysis on a subsample of 780 individual galaxies with i_AB<25 for which GALFIT converges for 429 of them. The individual median size (re~1 kpc), ellipticities (slightly elongated with (b/a)~0.45), Sérsic index (disk-like with n<2) and light concentration (comparable to that of disk or irregular galaxies, with C~2.7) of LAEs show mild evolution from z~2 to z~6. LAEs with the highest rest-frame equivalent widths (EW) are the smallest/most compact (re~0.8 kpc, compared to re~1.5 kpc for the lower EW LAEs). When stacking our samples in bins of fixed Lya luminosity and Lya EW we find evidence for redshift evolution in n and C, but not in galaxy sizes. The evolution seems to be stronger for LAEs with 25<EW<100 Å. When compared to other SFGs, LAEs are found to be smaller at all redshifts. The difference between the two populations changes with redshift, from a factor of ~1 at z>5 to SFGs being a factor of ~2-4 larger than LAEs for z<2. This means that at the highest redshifts, where typical sizes approach those of LAEs, the fraction of galaxies showing Lya in emission (and with a high Lya escape fraction) should be much higher, consistent with observations.
Tracing ionized gas kinematics in Lyman-Break Analogs. Implications for star formation compactness and outflow properties
Universidad de La Serena（拉塞雷纳大学）；Instituto de Astrofísica de Andalucía (CSIC)（安达卢西亚天体物理研究所）；Centro de Estudios de Física del Cosmos de Aragón (CEFCA)（阿拉贡宇宙物理学研究中心）；INAF - Osservatorio Astronomico di Roma（意大利国家天文台罗马天文台）；Michigan Institute for Data Science, University of Michigan（密歇根大学数据科学研究所）
The Lyman-alpha and Continuum Origins Survey II: the connection between the escape of ionizing radiation and Lyman-alpha halos in star-forming galaxies
Stockholm University（斯德哥尔摩大学）；University of Minnesota（明尼苏达大学）；Johns Hopkins University（约翰斯·霍普金斯大学）；Space Telescope Science Institute（太空望远镜科学研究所）；CNRS, Centre de Recherche Astrophysique de Lyon UMR5574, Univ Lyon, Ens de Lyon（法国国家科学研究中心，里昂天体物理研究中心UMR5574，里昂大学，里昂高等师范学校）；Observatoire de Genève, Université de Genève（日内瓦天文台，日内瓦大学）
JWST, ALMA, and Keck Spectroscopic Constraints on the UV Luminosity Functions at z~7-14: Clumpiness and Compactness of the Brightest Galaxies in the Early Universe
Power-law Emission-line Wings and Radiation-Driven Superwinds in Local Lyman Continuum Emitters
University of Michigan（密歇根大学）；University of Geneva（日内瓦大学）；Space Telescope Science Institute（太空望远镜科学研究所）；Stockholm University（斯德哥尔摩大学）；University of Minnesota（明尼苏达大学）；Arizona State University（亚利桑那州立大学）；Zhejiang University（浙江大学）；University of Texas at Austin（得克萨斯大学奥斯汀分校）；Laboratory for Atmospheric and Space Physics（大气与空间物理实验室）；University of Edinburgh（爱丁堡大学）；University of Massachusetts Amherst（马萨诸塞大学阿默斯特分校）；Johns Hopkins University（约翰斯·霍普金斯大学）；Williams College（威廉姆斯学院）；University of Virginia（弗吉尼亚大学）；Northwestern University（西北大学）
Rest-Frame UV and Optical Structural Evolution of Narrowband-Selected Lyman-alpha Emitters at z = 2-7 with JWST/NIRCam
National Astronomical Observatory of Japan（日本国立天文台）；The University of Tokyo（东京大学）；Nara Prefectural University（奈良县立大学）；The Graduate University for Advanced Studies（综合研究大学院大学）；Tohoku University（东北大学）；EPFL（洛桑联邦理工学院）；Alma Mater Studiorum Università di Bologna（博洛尼亚大学）；INAF–Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所博洛尼亚天文与空间科学观测站）；Universität Heidelberg（海德堡大学）
First Frontier Field Constraints on the Cosmic Star-Formation Rate Density at z~10 - The Impact of Lensing Shear on Completeness of High-Redshift Galaxy Samples
The morphological evolution, AGN fractions, dust content, environments, and downsizing of massive green valley galaxies at 0.5<z<2.5 in 3D-HST/CANDELS
为了探讨红、绿、蓝星系群之间的演化联系，我们以5个3D-HST/CANDELS场中0.5<z<2.5的大质量（$M_* > 10^{10} M_{\odot} $）星系为样本，研究了这3个星系群的尘埃含量、形态、结构、活动星系核分数和环境。绿谷星系被发现有中等的尘埃衰减，并居住在中间的区域所占据的静止和恒星形成星系的UVJ图。与z<2的蓝色和红色星系相比，绿色星系具有中等的紧凑性和形态参数，如Sersic指数，浓度，Gini系数和星系20%最亮像素的二阶矩。上述发现似乎支持了这样一种假设，即当恒星形成星系被淬灭进入静止状态时，绿色星系正处于过渡阶段。z<2的绿色星系显示出最高的活动星系核分数，这表明活动星系核反馈可能在恒星形成猝灭中发挥了重要作用。对于2<z<2.5的大质量星系，红星系和绿星系的活动星系核分数都比蓝星系高，这意味着活动星系核反馈可能有助于保持z>2的红星系的静止。在z = 0.5时，绿星系和红星系的<1.5. Green and blue galaxies at z>局域密度分布相似，表明在z>0.5时，环境猝灭不是停止恒星形成的主要机制。作为质量的函数的三个人口的分数支持一个“缩小”淬火图片，大部分的恒星形成在更大质量的星系比低质量的星系早完成。
University of Hertfordshire（赫特福德大学）；Tata Institute of Fundamental Research（塔塔基础研究所）；National Research Institute of Astronomy and Geophysics (NRIAG)（国家天文与地球物理研究所）；University of Tasmania（塔斯马尼亚大学）；University of Southampton（南安普顿大学）；Indian Institute of Technology Indore（印多尔印度理工学院）
