Spectroscopic Study of Galaxy Formation and Evolution in the Early Universe

该项目的主要目的是获取所谓的高红移宇宙中相当早期的原星系演化过程的信息。这类目标物体的辐射大多从原来的紫外和光学波段转移到近红外波段，因此红外观测尤为重要。因此，我们利用京都大学开发的oh气辉抑制光谱仪，对几个高z星系以及agn型物体进行了高灵敏度分光光度测定，该光谱仪连接在夏威夷莫纳克亚天文台的2.2米望远镜上。在该项目期间的观测中，我们获得了2到3或更多红红色物体的非常特殊的光谱，显示出强烈的发射线，如h - α， [OIII]和[NeII]。其中一个极端天体的[OIII]线发射能量与光度h通带的比值高达75%，这表明即使是在最早阶段的星系也已经被金属元素污染了，或者正在非常活跃地产生富含金属的星际气体成分。我们还观察到一颗被尘埃包裹的类星体和一颗被倾倒的Ly-alpha类星体，这两颗类星体都可能是在原星系的早期进化阶段诞生的。我们也对附近活动星系核的中心区域进行了光谱观测，比如NGC1068和NGC7319，使用了新开发的近红外光谱仪和微透镜光学光谱仪，这些光谱仪连接在莫纳克亚山和莱蒙山天文台的望远镜上。光学观测揭示了中心附近气体的动态流入运动。另一方面，红外光谱显示在中心分子环面存在固体颗粒形式的有机成分。这些发现为模拟活动星系在致密分子气体起源及其化学历史方面的演化提供了信息。少

The primary purpose of the project is to obtain information on the evolutionary process of protogalaxies at fairly early stages in the so-called high redshift Universe. The radiation of such target objects is mostly shifted to near-infrared from the original ultraviolet and optical bands, so that infared observations is in particular important. We therefore conducted high sensitivity spectrophotometries towards a couple of high-z galaxies, as well as AGN-type objects exploiting the OH-airglow suppressed spectrograph which has been developed in Kyoto University and attached to the 2.2m telescope in the Mauna Kea observatory, Hawaii. In the observations made during the period of this project we obtained very peculiar spectra of objects in the redshit range from 2 to 3 or more, showing strong emission lines, such as H-alpha, [OIII], and [NeII]. One of the extreme objects has been found to have a ratio of the [OIII] line emission energy relative to that in the photometric H-passband as hig … More h as 75 percent, which is suggestive that even galaxies in the earliest stage are already contaminated by metalic elements, or are very actively producing metal-rich interstellar gaseous components. We have also observed a dust-enshrouded quasar and a dumped Ly-alpha quasar, both of which are pressumably in the early evolutionary stage born in protogalaxies.We have carried out spectroscopic observations of the central regions of nearby active galactic nuclei as well, such as NGC1068 and NGC7319, using the newly developed near-infrared spectrograph and the microlens-based optical spectrometer, attached to telescopes in the Mauna Kea as well as in the Mt.Lemmon observatory. The optical observations reveal a dynamical infall motion of gases in the central vicinity. On the other hand, the infrared spectra have shown the presence of organic compositions in the form of solid grains in the central molecular torus. These findings provide information to model evolution of active galaxies in terms of the origin of dense molecular gas and its chemical history. Less