A deep 150 MHz Giant Metrewave Radio Telescope survey in Eridanus

Abstract

We present results of a 150 MHz survey of a field centred on e Eridani, undertaken with the Giant Metrewave Radio Telescope (GMRT). The survey covers an area with a diameter of ∼2°, has a spatial resolution of ∼30 arcsec and a noise level of σ= 3.1 mJy at the pointing centre. These observations provide a deeper and higher resolution view of the 150 MHz radio sky than the 7C survey (although the 7C survey covers a much larger area). A total of 113 sources were detected, most are point-like, but 20 are extended. We present an analysis of these sources, in conjunction with the National Radio Astronomy Observatory (NRAO) Very Large Array (VLA) telescope Sky Survey (NVSS) (at 1.4 GHz) and VLA Low-frequency Sky Survey (VLSS) (at 74 MHz). This process allowed us to identify five Ultra-Steep Spectrum (USS) radio sources that are candidate high-redshift radio galaxies (HzRGs). In addition, we have derived the dN/dS distribution for these observations and compare our results with other low-frequency radio surveys.