Yuko KAKAZU
(Institut d'Astrophysique de Paris)
We present the preliminary results of our ongoing search for the 'Ultra-Strong Emission Line galaxies (USELs)' in the COSMOS field. The USELs, originally selected by their large color excesses in optical narrowband filters, are interesting population due to their unique selection criteria (Kakazu et al. 2007). They may correspond to: (1) AGNs, (2) young star-forming galaxies that contain very massive stars, and (3) extremely metal-poor galaxies. The existing narrow- and intermediate-band photometry in the COSMOS-21 dataset makes it ideal to investigate such population. In this talk, we show the statistical and photometric properties of the USELs found in the COSMOS field.