令天文学家欣喜的新望远镜,带来了观测宇宙最初十亿年星系无与伦比的新视角。天文学家在用韦布空间望远镜(James Webb Space Telescope,JWST)观测宇宙最初的几十亿年时,期待看到什么呢?哈勃望远镜的观测已经揭示了宇宙在不同的时期都拥...令天文学家欣喜的新望远镜,带来了观测宇宙最初十亿年星系无与伦比的新视角。天文学家在用韦布空间望远镜(James Webb Space Telescope,JWST)观测宇宙最初的几十亿年时,期待看到什么呢?哈勃望远镜的观测已经揭示了宇宙在不同的时期都拥有多姿多彩的星系。数十亿年前,星系是年轻、活跃,而且无序的——正等待着演化至我们现在看到的壮观的旋臂盘星系和椭圆星系。展开更多
Brightest Cluster Galaxies (BCGs) are mostly elliptical galaxies and very rarely have prominent star formations. We found that five out of 8,812 BCGs are E+A (i.e., post-starburst) galaxies, having an Hd absorpti...Brightest Cluster Galaxies (BCGs) are mostly elliptical galaxies and very rarely have prominent star formations. We found that five out of 8,812 BCGs are E+A (i.e., post-starburst) galaxies, having an Hd absorption line with an equivalent width 〉2.5 A and no distinct emission lines in [O II] and Ha-. The E+A features we identified from the BCGs for the first time are not as significant as those in general galaxies, indicating that historically the star formations were not very violent.展开更多
文摘令天文学家欣喜的新望远镜,带来了观测宇宙最初十亿年星系无与伦比的新视角。天文学家在用韦布空间望远镜(James Webb Space Telescope,JWST)观测宇宙最初的几十亿年时,期待看到什么呢?哈勃望远镜的观测已经揭示了宇宙在不同的时期都拥有多姿多彩的星系。数十亿年前,星系是年轻、活跃,而且无序的——正等待着演化至我们现在看到的壮观的旋臂盘星系和椭圆星系。
基金supported by the Liaoning Educational Foundation of China (Grant No.2009A646)the National Natural Science Foundation of China (Grant Nos.10773016,10821061 and 1083303)+1 种基金the National Key Basic Research Science Foundation of China (Grant No.2007CB815403)Funding for the creation and distribution of the SDSS Archive has been provided by the Alfred P.Sloan Foundation
文摘Brightest Cluster Galaxies (BCGs) are mostly elliptical galaxies and very rarely have prominent star formations. We found that five out of 8,812 BCGs are E+A (i.e., post-starburst) galaxies, having an Hd absorption line with an equivalent width 〉2.5 A and no distinct emission lines in [O II] and Ha-. The E+A features we identified from the BCGs for the first time are not as significant as those in general galaxies, indicating that historically the star formations were not very violent.