J/AJ/139/1695 Celestial Reference Frame at 24 and 43 GHz (Lanyi+, 2010)
The Celestial Reference Frame at 24 and 43 GHz. I. Astrometry.
Lanyi G.E., Boboltz D.A., Charlot P., Fey A.L., Fomalont E.B.,
Geldzahler B.J., Gordon D., Jacobs C.S., Ma C., Naudet C.J., Romney J.D.,
Sovers O.J., Zhang L.D.
<Astron. J., 139, 1695-1712 (2010)>
=2010AJ....139.1695L 2010AJ....139.1695L
ADC_Keywords: Fundamental catalog ; Positional data ; VLBI ; QSOs
Keywords: astrometry - catalogs - quasars: general - radio continuum: galaxies -
reference systems - techniques: interferometric
Abstract:
We present astrometric results for compact extragalactic objects
observed with the Very Long Baseline Array at radio frequencies of 24
and 43GHz. Data were obtained from ten 24-hr observing sessions made
over a five-year period. These observations were motivated by the need
to extend the International Celestial Reference Frame (ICRF) to higher
radio frequencies to enable improved deep space navigation after 2016
and to improve state-of-the-art astrometry. Source coordinates for 268
sources were estimated at 24GHz and for 131 sources at 43GHz.
Description:
Observations were made using the ten 25m antennas of the National
Radio Astronomy Observatory (NRAO) VLBA.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 88 268 Coordinates of sources at K band (24 GHz)
table3.dat 89 131 Coordinates of sources at Q band (43 GHz)
table4.dat 21 112 Sources observed unsuccessfully
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See also:
I/251 : VLBI International Celestial Reference Frame (ICRF) (Ma+, 1997)
J/AJ/127/3587 : VLBI ICRF. II (Fey+, 2004)
J/AJ/139/1713 : Celestial Reference Frame at 24 and 43GHz. II. (Charlot+, 2010)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- JName Source name based on J2000 position
(JHHMM+DDMM)
12- 19 A8 --- BName Source name based on B1950 position
(HHMM+DDd)
21- 24 F4.2 Jy S24 ?=- The total source flux density at 24GHz
from Table 2 of Paper II
26- 27 I2 h RAh Right ascension (J2000)
29- 30 I2 min RAm Right ascension (J2000)
32- 40 F9.6 s RAs Right ascension (J2000)
42 A1 --- DE- Declination sign (J2000)
43- 44 I2 deg DEd Declination (J2000)
46- 47 I2 arcmin DEm Declination (J2000)
49- 56 F8.5 arcsec DEs Declination (J2000)
58- 65 F8.6 s e_RAs rms uncertainty on RA
67- 73 F7.5 arcsec e_DEs rms uncertainty on DE
75- 80 F6.3 --- C.pos [-1/1] Correlation between right ascension and
declination
82- 83 I2 --- Nep Number of epochs at which source was observed
85- 88 I4 --- Nobs Number of pairs of group delay and phase
delay-rate measurements used in the
solutions to obtain the estimated position
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- JName Source name based on J2000 position
(JHHMM+DDMM)
12- 19 A8 --- BName Source name based on B1950 position
(HHMM+DDd)
21- 25 F5.2 Jy S43 The total source flux density at 43GHz
from Table 3 of Paper II
27- 28 I2 h RAh Right ascension (J2000)
30- 31 I2 min RAm Right ascension (J2000)
33- 41 F9.6 s RAs Right ascension (J2000)
43 A1 --- DE- Declination sign (J2000)
44- 45 I2 deg DEd Declination (J2000)
47- 48 I2 arcmin DEm Declination (J2000)
50- 57 F8.5 arcsec DEs Declination (J2000)
59- 66 F8.6 s e_RAs rms uncertainty on RA
68- 74 F7.5 arcsec e_DEs rms uncertainty on DE
76- 81 F6.3 --- C.pos [-1/1] Correlation between right ascension and
declination
84 I1 --- Nep [1/10] Number of epochs at which the source
was observed
87- 89 I3 --- Nobs Number of pairs of group delay and phase
delay-rate measurements used in the
solutions to obtain the estimated position
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- JName Source name based on J2000 position (JHHMM+DDMM)
12- 19 A8 --- BName Source name based on B1950 position (HHMM+DDd)
21 A1 --- Band [KQ] Observed band (k=24GHz, Q=43GHz)
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History:
From electronic version of the journal
References:
Charlot et al., Paper II, 2010AJ....139.1713C 2010AJ....139.1713C, Cat. J/AJ/139/1713
(End) Patricia Vannier [CDS] 21-May-2012