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R-Band Imaging of Fields Around 1<z<2 Radiogalaxies

N. Benitez·E. Martinez-Gonzalez·J. I. Gonzalez-Serrano·L. Cayon
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Abstract

We have taken deep $R$-band images of fields around five radiogalaxies: 0956+47, 1217+36, 3C256, 3C324 and 3C294 with $1<z<2$ . 0956+47 is found to show a double nucleus. Our data on 1217+36 suggest the revision of its classification as a radiogalaxy. We found a statistically significant excess of bright ($19.5<R<22$) galaxies on scales of 2 arcmin around the radiogalaxies (which have $R \approx 21.4$) in our sample. The excess has been determined empirically to be at $\gtrsim 99.5\%$ level. It is remarkable that this excess is not present for $22<R<23.75$ galaxies within the same area, suggesting that the excess is not physically associated to the galaxies but due to intervening groups and then related to gravitational lensing.

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N. Benitez, E. Martinez-Gonzalez, J. I. Gonzalez-Serrano, L. Cayon. 1994-12-21. R-Band Imaging of Fields Around 1<z<2 Radiogalaxies. https://doi.org/10.1086/117332

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