J/A+A/529/A91 Proper motions of 555 quasars from VLBI (Titov+, 2011)
VLBI measurement of the secular aberration drift.
Titov O., Lambert S.B., Gontier A.-M.
<Astron. Astrophys. 529, A91 (2011)>
=2011A&A...529A..91T 2011A&A...529A..91T
ADC_Keywords: QSOs ; Positional data ; Interferometry ; Proper motions
Keywords: astrometry - reference systems - techniques: interferometric
Abstract:
While analyzing decades of very long baseline interferometry (VLBI)
data, we detected the secular aberration drift of the extragalactic
radio source proper motions caused by the rotation of the Solar System
barycenter around the Galactic center. Our results agree with the
predicted estimate to be 4-6 micro arcseconds per year (uas/yr)
towards RA=266° and DE=-29°. In addition, we tried to detect
the quadrupole systematics of the velocity field.
The analysis method consisted of three steps. First, we analyzed
geodetic and astrometric VLBI data to produce radio source coordinate
time series. Second, we fitted proper motions of 555 sources with long
observational histories over the period 1990-2010 to their
respective coordinate time series. Finally, we fitted vector spherical
harmonic components of degrees 1 and 2 to the proper motion field.
Description:
The file contains the mean positions and proper motions of 555 sources
used to adjust the secular aberration drift.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list555.dat 94 555 Position and proper motions of 555 quasars
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See also:
I/251 : VLBI International Celestial Reference Frame, ICRF (Ma+, 1997)
J/A+A/355/398 : Celestial Ephemeris Origin definition (Capitaine+, 2000)
J/AZh/81/1032 : VLBI position measurements (Titov, 2004)
Byte-by-byte Description of file: list555.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- IERS Radio source IERS designation
9- 18 I10 --- N Number of sessions after 1990
19- 36 F18.12 deg RAdeg Averaged right ascension, J2000
37- 54 F18.12 deg DEdeg Averaged declination, J2000
55- 64 F10.2 uas/yr pmRA Proper motion in right ascension, pmRA*cosDE
65- 74 F10.2 uas/yr pmDE Proper motion in declination
75- 84 F10.2 uas/yr e_pmRA rms uncertainty on pmRA
85- 94 F10.2 uas/yr e_pmDE rms uncertainty on pmDE
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Acknowledgements:
Sebastien Lambert, sebastien.lambert(at)obspm.fr
(End) Patricia Vannier [CDS] 15-Mar-2011