Large scale structures around radio galaxies at z ~ 1.5
MetadataShow full item record
We explore the environments of two radio galaxies at z ~ 1.5, 7C 1751+6809 and 7C 1756+6520, using deep optical and near-infrared imaging. Our data cover 15 × 15 arcmin2 fields around the radio galaxies. We develop and apply BzK color criteria to select cluster member candidates around the radio galaxies and find no evidence of an overdensity of red galaxies within 2Mpc of 7C 1751+6809. In contrast, 7C 1756+6520 shows a significant overdensity of red galaxies within 2Mpc of the radio galaxy, by a factor of 3.1±0.8 relative to the four MUSYC fields. At small separation (r > 6:"), this radio galaxy also has one z > 1.4 evolved galaxy candidate, one z > 1.4 star-forming galaxy candidate, and an AGN candidate (at indeterminate redshift). This is suggestive of several close-by companions. Several concentrations of red galaxies are also noticed in the full 7C 1756+6520 field, forming a possible large-scale structure of evolved galaxies with a NW-SE orientation. We construct the color-magnitude diagram of red galaxies found near 7C 1756+6520 (r < 2 Mpc), and find a clear red sequence that is truncated at Ks ~ 21.5 (AB). We also find an overdensity of mid-infrared selected AGN in the surroundings of 7C 1756+6520. These results are suggestive of a proto-cluster at high redshift. © 2009 ESO.
Showing items related by title, author, creator and subject.
Banfield, J.; Wong, O.; Willett, K.; Norris, R.; Rudnick, L.; Shabala, S.; Simmons, B.; Snyder, C.; Garon, A.; Seymour, Nick; Middelberg, E.; Andernach, H.; Lintott, C.; Jacob, K.; Kapinska, A.; Mao, M.; Masters, K.; Jarvis, M.; Schawinski, K.; Paget, E.; Simpson, R.; Klöckner, H.; Bamford, S.; Burchell, T.; Chow, K.; Cotter, G.; Fortson, L.; Heywood, I.; Jones, T.; Kaviraj, S.; López-Sánchez, R.; Maksym, W.; Polsterer, K.; Borden, K.; Hollow, R.; Whyte, L. (2015)We present results from the first 12 months of operation of Radio Galaxy Zoo, which upon completion will enable visual inspection of over 170 000 radio sources to determine the host galaxy of the radio emission and the ...
Kapiñska, A.; Terentev, I.; Terentev, W.; Shabala, S.; Shabala, A.; Rudnick, L.; Storer, L.; Banfield, J.; Willett, K.; Willett, F.; Willett, C.; Willett, A.; Middelberg, E.; Norris, R.; Norris, K.; Seymour, Nick; Simmons, B. (2017)Hybrid morphology radio sources (HyMoRS) are a rare type of radio galaxy that display different Fanaroff-Riley classes on opposite sides of their nuclei. To enhance the statistical analysis of HyMoRS, we embarked on a ...
Doherty, M.; Tanaka, M.; De Breuck, C.; Ly, C.; Kodama, T.; Kurk, J.; Seymour, Nick; Vernet, J.; Stern, D.; Venemans, B.; Kajisawa, M.; Tanaka, I. (2010)We present a spectroscopic campaign to follow-up red colour-selected candidate massive galaxies in two high redshift proto-clusters surrounding radio galaxies. We observed a total of 57 galaxies in the field of MRC0943-242 ...