Extended Lyman-alpha emitters in and around a proto-cluster at z=3.1
Abstract
Here we present our result of deep and wide-field narrow-band imaging of the region of the "proto-cluster" at z=3.1 around the SSA22 field. We detected 283 highly confident Lyα emitter candidates (LAEs) and discovered that the belt-like high surface density region of these LAEs extends over ≈ 60 Mpc in comoving scale, which is much larger than it was known previously. We then successfully detected the 35 extended Lyα blobs (LABs) which are larger than 16 arcsec2 in isophotal area and brighter than 0.7 × 10-16 ergs s-1 cm-2. The distributions of average surface brightness and morphology are widespread from relatively compact high surface brightness objects to very diffuse low surface brightness ones. For one third of these 35 LABs, simple photo-ionization by massive stars is not sufficient to explain the Lyα luminosities, and other mechanisms, such as gravitational heating or superwind must be considered. From their large size and strong spatial clustering, we consider that these LABs are objects closely related to the massive galaxies in their forming phase in the environment of the proto-cluster or large-scale structure.
- Publication:
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IAU Colloq. 195: Outskirts of Galaxy Clusters: Intense Life in the Suburbs
- Pub Date:
- July 2004
- DOI:
- Bibcode:
- 2004ogci.conf..468Y