J/MNRAS/390/741 150MHz GMRT survey in Eridanus (George+, 2008)
A deep 150MHz Giant Metrewave Radio Telescope survey in Eridanus.
George S.J., Stevens I.R.
<Mon. Not. R. Astron. Soc., 390, 741-751 (2008)>
=2008MNRAS.390..741G 2008MNRAS.390..741G
ADC_Keywords: Radio sources ; Surveys
Keywords: surveys - galaxies: active - galaxies: starburst -
radio continuum: general
Abstract:
We present results of a 150MHz survey of a field centred on ε
Eridani, undertaken with the Giant Metrewave Radio Telescope (GMRT).
The survey covers an area with a diameter of ∼2°, has a spatial
resolution of ∼30arcsec and a noise level of σ=3.1mJy at the
pointing centre. These observations provide a deeper and higher
resolution view of the 150MHz 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 1.4GHz) and VLA Low-frequency Sky
Survey (VLSS) (at 74MHz). 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.
Description:
The radio observations discussed here were conducted with the GMRT,
during cycle 11 on 2006 August 10 and lasted for duration of 4.13h.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 91 113 The complete GMRT 150MHz source catalogue
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [GMRT]
5- 20 A16 --- [GS2008] GMRT source name (JHHMMSS.s+DDMMSS)
23- 24 I2 h RAh Right ascension (J2000)
26- 27 I2 min RAm Right ascension (J2000)
29- 33 F5.2 s RAs Right ascension (J2000)
35 A1 --- DE- Declination sign (J2000)
36- 37 I2 deg DEd Declination (J2000)
39- 40 I2 arcmin DEm Declination (J2000)
42- 45 F4.1 arcsec DEs Declination (J2000)
47- 52 F6.1 mJy Bpeak Peak brightness at 150MHz (in mJy/beam)
54- 59 F6.1 mJy S150 ? Flux density at 150MHz (only given for
resolved sources)
60 A1 --- n_S150 [*] Note on S150MHz (1)
63- 66 F4.1 mJy e_Bpeak ? 1sigma error on Bpeak for point sources
68- 72 F5.2 mJy e_S150 ? 1sigma error on S150MHz for resolved ones
74- 78 F5.1 arcsec theta Angular size
80- 85 F6.1 mJy SNVSS ? NVSS 1.4GHz peak flux
86 A1 --- n_SNVSS [+] Note on SNVSS (1)
88- 91 I4 mJy SVLSS ? VLSS 74MHz peak flux
--------------------------------------------------------------------------------
Note (1): Note as follows:
* = the source flux was determined by manual inspection using the
AIPS task TVSTAT. See text for further details of these parameters.
+ = These sources appear to be distinct objects in the GMRT
observations but appear as one unresolved source in the NVSS.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 30-Apr-2009