Using Subaru telescope and Suprime-Cam, the prime-focus wide-field camera, we have conducted the deep and very wide-field survey of Ly Alpha emission- and absorption-line objects at z=3. The survey area, in total of 3 square degrees, consists of the known high-density region of star-forming galaxies at z=3.1 (about 1.7 sq. deg. at SA22 fields) and other general control fields (about 1.3 sq. deg at GOODS-N, Subaru Deep Field, Subaru/XMM-Newton Deep Survey Field). We detected more than 2000 LyA emitters with very high significance and, maybe for the first time, evaluated the reliable overdensity of LyA emitters at ~30Mpc (comoving) scale for the density peak by using the sufficiently deep and multi-field control samples. Comparing the results with the prediction in the hierarchical structure-formation models, we found that the density peak is extremely rare one, if the Gaussian distribution of the density fluctuation is assumed. We also investigated the rest-frame equivalent-width (EW) distribution of the LyA emitters and found that at least more than 150 galaxies have EW larger than 240A, which suggests the star-formation under very metal-poor environments with top-heavy initial mass function. We are also studying the LyA Blobs (extended giant LyA nebular), LyA absorbers, and IR-selected objects in the fields.
The subject will be presented with a brief review of the wide-field astronomy using Subaru Suprime Cam and MOIRCS, our new wide-area infrared camera and spectrograph.

Toru Yamada