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Description
Foreground removal is a major challenge for detecting the redshifted 21-cm neutral hydrogen (HI) signal from the Epoch of Reionization. The authors have used 150-MHz Giant Metrewave Radio Telescope (GMRT) observations to characterize the statistical properties of the foregrounds in four different fields of view. The observational data were used to assess point source subtraction. Considering the brightest source (~1 Jy) in each field, the authors find that the residual artefacts are less than 1.5% in the most sensitive field (FIELD I). Considering all the sources in the fields, they find that the bulk of the image is free of artefacts, the artefacts being localized to the vicinity of the brightest sources. The authors have used FIELD I, which has an rms noise of 1.3 mJy beam<sup>-1</sup>, to study the properties of the radio source population to a limiting flux of 9 mJy. The differential source count is well fitted with a single power law of slope -1.6. They find there is no evidence for flattening of the source counts towards lower flux densities which suggests that source population is dominated by the classical radio-loud active galactic nuclei. The authors have observed FIELD I in GMRT Time Allocation Committee (GTAC) cycle 15 in 2008 January, whereas FIELD II and FIELD III were observed in cycle 17 during 2010 February. These target fields were selected at high Galactic latitudes (b > 10<sup>o</sup>) which were up at night time during the GTAC cycles 15 and 17, and which contain relatively few bright sources (>= 0.3 Jy) in the 1400 MHz NRAO VLA Sky Survey (NVSS). Finally, FIELD IV was observed in cycle 8 (2005 June). Full details of these 4 observations are given in Table 1 of the reference paper. This table contains the 150-MHz source catalog for the most sensitive observation, namely the 9.8-hour observation of Field I (centered on J2000.0 RA and Dec of 5<sup>h</sup> 30<sup>m</sup> 00<sup>s</sup>, +60<sup>o</sup> 00' 00"), which was made on 2008 January 8. This table was created by the HEASARC in September 2013 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/426/3295">CDS Catalog J/MNRAS/426/3295</a> file tablea1.dat This is a service provided by NASA HEASARC .
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