J/AJ/133/906 Radio star proper motions (Boboltz+, 2007)
Very Large Array plus Pie Town astrometry of 46 radio stars.
Boboltz D.A., Fey A.L., Puatua W.K., Zacharias N., Claussen M.J.,
Johnston K.J., Gaume R.A.
<Astron. J., 133, 906-916 (2007)>
=2007AJ....133..906B 2007AJ....133..906B
ADC_Keywords: Positional data ; Radio sources ; Interferometry ; Proper motions
Keywords: astrometry - binaries: close - radio continuum: stars -
techniques: interferometric
Abstract:
We have used the Very Large Array, linked with the Pie Town Very Long
Baseline Array antenna, to determine astrometric positions of 46 radio
stars in the International Celestial Reference Frame (ICRF). Positions
were obtained in the ICRF directly through phase referencing of the
stars to nearby ICRF quasars whose positions are accurate at the
0.25mas level. Radio star positions are estimated to be accurate at
the 10mas level, with position errors approaching a few
milliarcseconds for some of the stars observed. Our measured positions
were combined with previous measurements taken from as early as 1978
to obtain proper-motion estimates for all 46 stars with average
uncertainties of ∼1.7mas/yr.
Description:
The VLA+PT radio observations occurred over three epochs: 2003 June
6-7, 2003 September 9-10, and 2004 October 18-19. Data for all three
epochs were recorded in dual circular polarization using two adjacent
50MHz bands centered on rest frequencies of 8460.1 and 8510.1MHz.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 64 46 Observed radio stars and corresponding ICRF
calibrator sources
table2.dat 77 47 Radio star positions estimated from the VLA+PT data
table3.dat 58 47 Radio star position uncertainties and
offsets from Hipparcos
table4.dat 52 46 Radio star proper-motions
table5.dat 58 46 Radio star proper-motion uncertainties and
offsets from Hipparcos
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See also:
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
I/251 : VLBI International Celestial Reference Frame (ICRF) (Ma+ 1997)
J/AJ/127/3587 : VLBI ICRF. II (Fey+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Star name
11- 16 I6 --- HIP Hipparcos number (HIP NNNNNN in Simbad)
18- 25 A8 --- ICRF ICRF calibrator (IERS name)
27 A1 --- n_ICRF [CDNO] ICRF category (1)
29- 30 I2 h RAh Hour of Right Ascension (J2000.0) (2)
32- 33 I2 min RAm Minute of Right Ascension (J2000.0) (2)
35- 43 F9.6 s RAs Second of Right Ascension (J2000.0) (2)
45 A1 --- DE- Sign of the Declination (J2000.0) (2)
46- 47 I2 deg DEd Degree of Declination (J2000.0) (2)
49- 50 I2 arcmin DEm Arcminute of Declination (J2000.0) (2)
52- 59 F8.5 arcsec DEs Arcsecond of Declination (J2000.0) (2)
61- 64 F4.1 deg Sep Separation between the target and the ICRF
reference source.
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Note (1): ICRF source category (Ma et al. 1998, Cat. I/251; Gambis 1999,
IERS Annu. Rep. (Paris: Obs. Paris) p. 87; Fey et al. 2004, Cat.
J/AJ/127/3587), defined as follows:
D = defining;
C = candidate;
O = other;
N = new in ICRF extension 1.
Note (2): ICRF extension 1 source positions (Gambis 1999, IERS Annu. Rep.
(Paris: Obs. Paris) p. 87).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Star name
10 A1 --- n_Name [*] Note on Name (1)
11- 16 I6 --- HIP Hipparcos number (HIP NNNNNN in Simbad)
18- 19 I2 h RAh Hour of Right Ascension (J2000.0)
21- 22 I2 min RAm Minute of Right Ascension (J2000.0)
24- 30 F7.4 s RAs Second of Right Ascension (J2000.0)
32- 37 F6.4 s e_RAs Error on RAs (in seconds of time)
39- 43 F5.3 arcsec eRAs Error on RAs (in seconds of arc)
45 A1 --- DE- Sign of the Declination (J2000.0)
46- 47 I2 deg DEd Degree of Declination (J2000.0)
49- 50 I2 arcmin DEm Arcminute of Declination (J2000.0)
52- 57 F6.3 arcsec DEs Arcsecond of Declination (J2000.0)
59- 63 F5.3 arcsec e_DEs Error on DEs
65- 73 F9.4 yr Epoch Epoch of observation
75 I1 --- Ns Number of successful observations
76 A1 --- --- [/]
77 I1 --- Nt Number of total observations (scans)
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Note (1): HD 193793 was observed in experiments AF399a and AJ315.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Star name
10 A1 --- n_Name [*] Note on Name (1)
11- 16 I6 --- HIP Hipparcos number (HIP NNNNNN in Simbad)
18- 21 F4.1 mas e_RAR Radio error in Right Ascension (RAcosDE)
23- 26 F4.1 mas e_DER Radio error in Declination
28- 31 F4.1 mas e_RAH Hipparcos error in Right Ascension
(RAcosDE) (2)
33- 36 F4.1 mas e_DEH Hipparcos error in Declination (2)
38- 41 F4.1 mas e_RA Combined error in Right Ascension
(RAcosDE) (3)
43- 46 F4.1 mas e_DE Combined error in Declination (3)
48- 52 F5.1 mas dRA Offset ΔHip-Rad (RAcosDE)
54- 58 F5.1 mas dDE Offset ΔHip-Rad
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Note (1): HD 193793 was observed in experiments AF399a and AJ315.
Note (2): Hipparcos uncertainties updated to the epoch of our observations
using the Hipparcos proper-motion uncertainties.
Note (3): Combined uncertainties are the rss (root sum square) of our
VLA+PT errors and the corresponding Hipparcos errors at epoch.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Star name
11- 16 I6 --- HIP Hipparcos number (HIP NNNNNN in Simbad)
18- 24 F7.2 mas/yr pmRA Proper motion in Right Ascension (pmRA*cosDE)
26- 29 F4.2 mas/yr e_pmRA Error in pmRA
31- 37 F7.2 mas/yr pmDE Proper motion in Declination
39- 42 F4.2 mas/yr e_pmDE Error in pmDE
44 I1 --- Npos Number of position measurements (1)
46- 52 F7.4 yr DeltaT Time between first and last position epochs
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Note (1): Number of position measurements used in the weighted
least-squares fit to estimate the proper motion.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Star name
11- 16 I6 --- HIP Hipparcos number (HIP NNNNNN in Simbad)
18- 21 F4.2 mas/yr e_pmRAR Radio error in pmRA*cosDE
23- 26 F4.2 mas/yr e_pmDER Radio error in pmDE
28- 31 F4.2 mas/yr e_pmRAH Hipparcos error in pmRA*cosDE
33- 36 F4.2 mas/yr e_pmDEH Hipparcos error in pmDE
38- 41 F4.2 mas/yr e_pmRAc Combined error in pmRA (1)
43- 46 F4.2 mas/yr e_pmDEc Combined error in pmDE (1)
48- 52 F5.2 mas/yr dpmRA Offset ΔHip-Rad for pmRA*cosDE
54- 58 F5.2 mas/yr dpmDE Offset ΔHip-Rad for pmDE
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Note (1): Combined uncertainties are the rss (root sum square) of our radio
errors and the corresponding Hipparcos errors at epoch.
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History:
From electronic version of the journal
(End) Marianne Brouty [CDS] 15-Oct-2009