An optical source catalog of the north ecliptic pole region

作者：Hwang Narae^*; Lee Myung Gyoon; Lee Hyung Mok; Im Myungshin; Kim Taehyun; Matsuhara Hideo; Wada Takehiko; Oyabu Shinki; Pak Soojong; Chun Moo Young; Watarai Hidenori; Nakagawa Takao; Pearson Chris; Takagi Toshinobu; Hanami Hitoshi; White Glenn J

来源：Astrophysical Journal, The - Supplement Series, 2007, 172(2): 583-598.

DOI：10.1086/519216

• catalogs
• galaxies : clusters : general
• galaxies : general
• galaxies : photometry

We present a five-band (u(*), g', r', i', z') optical photometry catalog of the sources in the north ecliptic pole (NEP) region based on deep observations made with MegaCam at CFHT. The source catalog covers about 2 square degree area centered at the NEP and reaches depths of about 26 mag for u*, g', r' bands, about 25 mag for i' band, and about 24 mag for z' band (4 sigma detection over a 100 aperture). The total number of cataloged sources brighter than r' 23 mag is about 56,000 including both point sources and extended sources. From the investigation of photometric properties using the color-magnitude diagrams and color-color diagrams, we have found that the colors of extended sources are mostly (u*- r') < 3: 0 and (g'- z') > 0.5. This can be used to separate the extended sources from the point sources reliably, even for the faint source domain where typical morphological classification schemes hardly work efficiently. We have derived an empirical color-redshift relation of the red sequence galaxies using the Sloan Digital Sky Survey data. By applying this relation to our photometry catalog and searching for any spatial overdensities, we have found two galaxy clusters and one nearby galaxy group.

• 出版日期2007-10