J/AZh/74/42 RATAN-600 radio sources spectra (Bursov 1997)
Spectra of weak radio sources from the RATAN-600 "Kholod" deep survey
Bursov N.N
<Astron. Zh., 74, 42 (1997)>
=1997AZh....74...42B 1997AZh....74...42B (SIMBAD/NED BibCode)
=1997ARep...41...35B 1997ARep...41...35B
ADC_Keywords: Radio sources ; Spectroscopy
Abstract:
A multifrequency deep survey of a band of sky with the declination of
the source SS 433 (δ∼5°±20') was performed as part of the
"Kholod" program on the RATAN-600 in 1987-1988. The right ascension
intervals covered by the survey are 0h<α<14h and
18h<α<24h. The spectral properties of 400 sources from the RC
catalog were determined for the first time by using only RATAN-600
data. The maximum in the flux density distribution for these sources
at the central wavelength, λ7.6cm, occurs at ∼30mJy. The lower
flux limits for the sample at wavelengths of 3.9, 7.6, 13.0, and
31.0cm are 16, 9, 37, and 61mJy, respectively. These observations
provide the first flux estimates at 13.0 and 31.0cm for 90% of the
sources. Spectra were measured for the first time for 112 sources
(28%) and were revised for 90 sources (23%). The maximum in the
spectral index distribution for the entire sample in the interval from
λλ7.6-31.0cm occurs at α=-0.86±0.04
(Sv~να). The spectra of some 20 of the sample sources
(5%) are peaked at roughly 1GHz, and about 40 spectra (10%) have
low-frequency breaks. Roughly 70 sources (19%) have flat spectra
(α>-0.5), and 64 (18%) have very steep spectra (α←1.1).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 100 400 Flux densities for RC radio sources (1988.0)
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See also:
VIII/33 : Spectral characteristics of RATAN (RC) Catalog (Bursov+ 1989)
J/A+AS/87/1 : RATAN-600 7.6 cm radio sources catalog (Parijskij+ 1991)
J/other/BSAO/40.128 : RATAN-600 radio sources spectra (Bursov 1996)
J/other/BSAO/40.5 : RATAN-600 RC radio sources (Parijskij+ 1996)
J/A+A/370/78 : RATAN-600 NCP bright radio sources (Mingaliev+, 2001)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/400]+ Sequential number
5- 14 A10 --- RC Name of the source in the RC catalogue derived
from the coordinates for the epoch J2000
16 A1 --- n_RC [cn] Corrected or new spectrum (1)
18- 19 I2 h RAh Right ascension (1950)
21- 22 I2 min RAm Right ascension (1950)
24- 28 F5.2 s RAs Right ascension (1950)
30 A1 --- DE- Declination sign
31- 32 I2 deg DEd Declination (1950)
34- 35 I2 arcmin DEm Declination (1950)
37- 40 F4.1 arcsec DEs Declination (1950)
42- 47 F6.2 arcmin Shift Shift in height {DELTA}h from the centre
of the antenna beam
48 A1 --- l_S3.9cm Limit flag on S3.9cm
49- 52 I4 mJy S3.9cm ? Flux density at λ3.9cm (7GHz)
53 A1 --- n_S3.9cm [n] n: Flux values is lacking
54- 56 I3 mJy e_S3.9cm ? rms uncertainty on S3.9cm
57 A1 --- l_S7.6cm Limit flag on S7.6cm (3.9GHz)
58- 61 I4 mJy S7.6cm ? Flux density at λ7.6cm
62 A1 --- n_S7.6cm [n] n: Flux values is lacking
63- 65 I3 mJy e_S7.6cm ? rms uncertainty on S7.6cm
66 A1 --- l_S13.0cm Limit flag on S13.0cm
67- 70 I4 mJy S13.0cm ? Flux density at λ13.0cm (2.3GHz)
71 A1 --- n_S13.0cm [n] n: Flux values is lacking
72- 74 I3 mJy e_S13.0cm ? rms uncertainty on S13.0cm
76 A1 --- l_S31.0cm Limit flag on S31.0cm
77- 80 I4 mJy S31.0cm ? Flux density at λ31.0cm (0.96GHz)
81 A1 --- n_S31.0cm [n] n: Flux values is lacking
82- 84 I3 mJy e_S31.0cm ? rms uncertainty on S31.0cm
86- 90 F5.2 --- SI ? Calculated spectral index from
λλ7.6-31.0cm
92-100 A9 --- Spectrum Type of the source spectrum (2)
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Note (1): n: sources with the spectra obtained for the first time
c: sources with revised or corrected spectra
For the rest of the sources, spectra was added
Note (2): Types from the classification of Kellerman (1974, in, Galactic and
Extragalactic Radio Astronomy, ed: G.L. Verschuur and K.I. Kellerman,
Springer-Verlag, berlin, Heildelberg, New-York, 320.).
S: linear power-law spectra associated with extended optically thin
radio sources.
C-: The spectrum has a negative second derivative of the dependence
logS-logν and is more steep at the short wavelengths. Such
spectra are also assigned to extended radio sources
Cmax: The power spectrum (class S) or dual power spectrum (class C-) at
short waves, but there is a sharp cut off at the long wavelengths.
Such spectra are produced by compact optically thick sources.
C+: The spectrum has positive curvature with a rise at the long or the
short wavelengths.
CPX: Complex spectra with one or more minima. The spectra are generally
believed to be composed of two or more spectra of class Cmax plus,
in some case, of class S. The spectra of this class are also
assigned to compact optically thick objects.
F: Flat spectra
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History: Prepared via OCR at CDS.
(End) James Marcout, Patricia Bauer [CDS] 16-Nov-1998