J/A+A/471/1105 XMM-LSS at 240MHz and 610MHz (Tasse+, 2007)
GMRT observations of the XMM Large Scale Structure Survey field.
Tasse C., Roettgering H.J.A., Best P.N., Cohen A.S., Pierre M., Wilman R.
<Astron. Astrophys. 471, 1105 (2007)>
=2007A&A...471.1105T 2007A&A...471.1105T
ADC_Keywords: Surveys ; Active gal. nuclei ; Radio sources
Keywords: techniques: interferometric - methods: statistical - surveys -
galaxies: active - radio continuum: galaxies -
cosmology: large-scale structure of Universe
Abstract:
The low-frequency radio survey of the XMM-Large Scale Structure
(XMM-LSS) field aims to study the connection between the extragalactic
radio source populations and their environment as traced by X-ray and
optical emission. In this paper we present new radio observations of
the XMM-LSS field carried out using the Giant Meterwave Radio
Telescope at 240 and 610MHz. These observations complement the
observations presented by Cohen at al. (2003, Cat. J/ApJ/591/640)
and Tasse et al. (2006, Cat. J/A+A/456/791) at 74 and 325MHz with
the Very Large Array. At 240 and 610MHz, we reach noise levels of
∼2.5 and ∼0.3mJy/beam, leading to the detection of 466 and 769
sources over 18.0 and 12.7 degree2 with resolutions of 14.7arcsec
and 6.5arcsec respectively. Combining these data with the available
source lists at 74, 325 (Tasse et al., 2006, Cat. J/A+A/456/791) and
1400MHz (NVSS), we build a multifrequency catalogue containing 1611
radio sources. We check for consistency of the astrometry and flux
density estimates. We fit a simple synchrotron radiation model to the
flux density measurements of the 318 radio sources being detected in
at least 4 bands. While ∼26% of them show signature of spectral
ageing, ∼6% show self absorption.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 118 571 The 240MHz source list
table4.dat 118 1037 The 610MHz source list
table5.dat 131 318 Fitting parameters
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See also:
J/ApJ/591/640 : XMM-LSS low-frequency radio counterparts (Cohen+, 2003)
J/A+A/439/413 : XMDS/VVDS 4σ catalogue (Chiappetti+, 2005)
J/A+A/456/791 : XMM-LSS field at 74 and 325MHz (Tasse+, 2006)
Byte-by-byte Description of file: table[34].dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Source Name (JHHMM.m+DDMM)
14- 15 I2 h RAh Right ascension (J2000)
17- 18 I2 min RAm Right ascension (J2000)
20- 24 F5.2 s RAs Right ascension (J2000)
26- 29 F4.2 arcsec e_RAs rms uncertainty on RA
31 A1 --- DE- Declination sign (J2000)
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 42 F5.2 arcsec DEs Declination (J2000)
44- 47 F4.2 arcsec e_DEs rms uncertainty on DE
49 A1 --- Type [SMC] Source type: (S)ingle, (M)ultiple or
(C)omponent of multiple source
51- 57 F7.1 mJy Sint ? Total integrated flux density at 240MHz
(table3) or 610MHz (table4)
59- 64 F6.1 mJy e_Sint ? rms uncertainty on Sint
65 A1 --- n_Sint [*] *: flux calculated with pixel based method
66- 72 F7.1 mJy Scomp Integrated flux density of individual Gaussian
fitting component at 240MHz (table3)
or 610MHz (table4)
74- 79 F6.1 mJy e_Scomp rms uncertainty on Scomp
81 A1 --- l_amaj Limit flag on amaj
82- 85 F4.1 arcsec amaj Deconvolved size of major axis, or the 2σ
upper limit if the source is unresolved
87- 90 F4.1 arcsec e_amaj ? rms uncertainty on amaj
92 A1 --- l_amin Limit flag on amin
93- 96 F4.1 arcsec amin ?=- Deconvolved size of minor axis, or 2σ
upper limit if the source is unresolved
98-100 F3.1 arcsec e_amin ? rms uncertainty on amin
102-106 F5.1 deg PA ?=- Position angle of major axis
108-111 F4.1 deg e_PA ? rms uncertainty on PA
113 A1 --- l_SI Limit flag on SI
114-118 F5.2 --- SI ? Spectral index, with respect to NVSS flux
density (1.4GHz) (1)
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Note (1): Spectral index α2401400 for table3,
α6101400 for table4.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Name Source Name (JHHMM.m+DDMM)
14- 15 I2 h RAh Right ascension (J2000)
17- 18 I2 min RAm Right ascension (J2000)
20- 24 F5.2 s RAs Right ascension (J2000)
26- 29 F4.2 arcsec e_RAs rms uncertainty on RA
31 A1 --- DE- Declination sign (J2000)
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 42 F5.2 arcsec DEs Declination (J2000)
44- 47 F4.2 arcsec e_DEs rms uncertainty on DE
49- 54 F6.1 mJy S0 Best fit S0 parameter value
56- 60 F5.1 mJy E_S0 Upper limit of S0 68% confidence interval
62- 66 F5.1 mJy e_S0 Lower limit of S0 68% confidence interval
68- 72 F5.2 --- alpha Best fit spectral index α value
74- 77 F4.2 --- E_alpha Upper limit of alpha 68% confidence interval
79- 82 F4.2 --- e_alpha Lower limit of alpha 68% confidence interval
84- 89 F6.1 MHz nu1 ?=- Best fit ν1 parameter value
91- 95 F5.1 MHz E_nu1 ? Upper limit of nu1 68% confidence interval.
See note (1)
97-101 F5.1 MHz e_nu1 ? Lower limit of nu1 68% confidence interval.
See note (1)
102 A1 --- nenu1 [i] i for infinity
104-109 F6.1 MHz nuc ?=- Best fit νc parameter value
111-115 F5.1 MHz E_nuc ? Upper limit of nuc 68% confidence interval.
See note (2)
116 A1 --- nenuc [i] i for infinity
118-122 F5.1 MHz e_nuc ? Lower limit of nuc 68% confidence interval.
See note (2)
124-129 F6.2 --- log(chi2r) Least χ2reduced logarithmic value
131 A1 --- Class [0-3] Class indicator (3)
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Note (1): "---" means that the upper bound of the 68% confidence interval lies
below the lowest available frequency.
Note (2): "---" means that the lower bound of the 68% confidence interval lies
above the highest available frequency.
Note (3): Class indicator as follows:
1 = to fit the flux density points the model needs the presence of
self-absorption and no spectral aging
2 = to fit the flux density points the model needs the presence of
spectral aging and no self-absorption
3 = to fit the flux density points the model needs the presence of
self-absorption and spectral aging
0 = all other cases
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Acknowledgements:
Cyril Tasse, tasse(at)strw.leidenuniv.nl
(End) Patricia Vannier [CDS] 12-Jun-2007