NIR Narrow- and Broad-Band Study of the SSA 22 Field
Tadafumi Takata2001, Publications of the Astronomical Society of Japan
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Abstract
Deep narrow-and broad-band near-infrared imaging observations of the central 2 × 2 region of the SSA 22 field were made with the near-infrared camera (CISCO) attached to the Subaru Telescope. Using a narrow-band filter centered at 2.033 µm, [O III] λ 5007 emitters at z ∼ 3.06 ± 0.02 were searched to examine star-forming activities in an over-density region where a clustering of Lyman Break Galaxies (LBGs) and Lyman α emitter candidates around z = 3.09 was reported, though the targeted redshift is slightly different from that of the peak of the over-density region. Although one emitter candidate at z = 3.06 was detected, it is likely to be located at a redshift of between 1 and 2 judged based on multi-band photometry. Another emission-line object was detected in another narrowband filter ("off band" filter) centered at 2.120 µm, which is identified with a galaxy at z = 0.132 (the emission line is Paschen α). The K-band imaging data revealed the presence of 12 Extremely Red Objects (EROs) with I 814 −K ≥ 4. The distribution of the EROs does not seem to coincide with that of Lyman Break Galaxies or Lyman α emitters at z ∼ 3. The magnitudes and colors of the EROs are not consistent with those of passively evolving massive elliptical galaxies at z ∼ 3. Candidates for counterparts of the submm sources detected with SCUBA are found; no EROs around the submm sources are found in our magnitude limit.
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