J/A+A/559/A95 Fitted proper motions for the DR solution (Titov+, 2013)
Improved VLBI measurement of the solar system acceleration.
Titov O., Lambert S.
<Astron. Astrophys. 559, A95 (2013)>
=2013A&A...559A..95T 2013A&A...559A..95T
ADC_Keywords: Fundamental catalog ; Positional data; QSOs ; VLBI
Keywords: astrometry - reference systems
Abstract:
We propose new estimates of the secular aberration drift, mainly due
to the rotation of the Solar System about the Galactic center, based
on up-to-date VLBI observations and and improved method of outlier
elimination.
We fit degree-2 vector spherical harmonics to extragalactic radio
source proper motion field derived from geodetic VLBI observations
spanning 1979-2013. We pay particular attention to the outlier
elimination procedure to remove outliers from (i) radio source
coordinate time series and (ii) the proper motion sample.
We obtain more accurate values of the Solar system acceleration
compared to those in our previous paper. The acceleration vector is
oriented towards the Galactic center within ∼7°. The component
perpendicular to the Galactic plane is statistically insignificant. We
show that an insufficient cleaning of the data set can lead to strong
variations in the dipole amplitude and orientation, and statistically
biased results.
Description:
The file contains the mean positions and proper motions of 429 sources
used to adjust the secular aberration drift (the DR solution exismates
the Diploe and Rotation parameters)
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list429.dat 69 429 Position and proper motions of 429 quasars
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See also:
I/323 : International Celestial Reference Frame 2, ICRF2 (Ma+, 2009)
Byte-by-byte Description of file: list429.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- IERS Radio source IERS designation
(HHMM+DDd, B1950 equinox)
10- 13 I4 --- N Number of observing sessions
15- 25 F11.7 deg RAdeg Averaged right ascension (J2000)
27- 37 F11.7 deg DEdeg Averaged declination (J2000)
39- 45 F7.2 uas/yr pmRA [-110/110] Proper motion in right ascension (1)
47- 53 F7.2 uas/yr pmDE [-110/110] Proper motion in declination
56- 61 F6.2 uas/yr e_pmRA Error in proper motion in right ascension (1)
64- 69 F6.2 uas/yr e_pmDE Error in proper motion in declination
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Note (1): the value is multiplied by the cosine of the declination.
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Acknowledgements:
Sebastien Lambert, sebastien.lambert(at)obspm.fr
(End) Patricia Vannier [CDS] 16-Oct-2013