Wide Field Deep Survey for Ly α Emitters around a Large Scale Structure at Redshift 3.1

该项目的目标包括以下内容：（A）对在SSA 22油田发现的z=3.1（C.C.）的Lya发射体（LAE）大尺度结构（LLS）周围区域进行宽视场深测量。Steidel，ApJ 2000，& T. Hayashino，AJ 2004）揭示了在超大尺度下高红移星系的空间分布;（B）通过与控制场的比较揭示了在z=3.1的SSA 22 LLS中LAEs的数超密度;（C）揭示了在LSS中发现的LAEs的三维空间分布。通过对Subaru 2005密集计划获得的2平方度视场（200 Mpc × 100 Mpc，z=3.1，共动坐标系）的观测数据进行分析，得到了以下结果，基本达到了我们的项目目标。(1)我们对红移z=3.09±0.03的LAEs进行了窄带滤波（CW 497 nm/BW 8 nm）测量（共动空间60 Mpc切片），在SSA 22测区探测到约2000个LAEs，显示出强烈的大尺度不均匀分布，即：我们在先前发现的大射电望远镜西侧发现了另一个100 Mpc尺度的大射电望远镜，以及一个直径70 Mpc的大空洞。(2)结果表明，虽然SSA 22测区不仅含有大尺度散射体，而且还含有一个大空洞，但在200 Mpc × 100 Mpc × 60 Mpc的测区中，LAEs的数密度几乎是控制场中相同红移的两倍。标准的CDM结构形成场景可以仅以10 μ s的概率在z=3.1处构造这样的大的高密度区域<-8>。(3)通过对200个LAEs的光谱观测，我们发现了LSS中LAEs的三维结构，这是标准CDM模拟所期望的。

The aim of this project consists of the followings, (A) Wide field deep survey for the region around the large scale structure (LLS) of Lya emitters (LAEs) discovered in SSA22 field at z=3.1 (C.C. Steidel, ApJ 2000, & T. Hayashino, AJ 2004) to reveal spatial distribution of high redshift galaxies in very large scale, (B) To reveal number overdensity of LAEs in the SSA22 LLS at z=3.1 by comparimg with controle fields, and (C) To reveal three dimensional spatial distribution of LAEs in the LSS discovered. Analysing the observational data over two square degree field (200Mpc×100Mpc at z=3.1 in comoving frame) obtained by the Subaru 2005 Intensive Program, we have gotten the following results which almost reach the goal of our project described above. (1) We carried out narrowband filter (CW497nm/BW8nm) survey for LAEs with redshifts z=3.09±0.03(6OMpc slice of comoving space) to detect ～2000 LAEs in the SSA22 survey area, showing strong inhomogeneous distribution in large scales, i.e., we have discovered another LSS of 10OMpc scale in the west of the LSS previously discovered, together with a big void of 70Mpc in diameter. (2) We have revealed that number density of LAEs in the SSA22 survey volume of 200Mpc×100Mpc×6OMpc is almost twice of it at the same redshift in controle fields, though the SSA22 survey region contains not only LSSs but a big void. Standard CDM structure formation scenario is possible to construct such a large high density region at z=3.1 with only 10^<-8> probability. (3) We have found out three dimensional filamentary structure of LAEs in the LSS by spectroscopic observation of ～200 LAEs, which is expected in general by standard CDM simulations.