J/A+A/552/A98 Optical monitoring of extragalactic sources (Taris+, 2013)
Optical monitoring of extragalactic sources for the link between the ICRF and
the future Gaia celestial reference frame.
I. Variability of ICRF sources.
Taris F., Andrei A., Klotz A., Vachier F., Cote R., Bouquillon S.,
Souchay J., Lambert S., Anton S., Bourda G., Coward D.
<Astron. Astrophys. 552, A98 (2013)>
=2013A&A...552A..98T 2013A&A...552A..98T
ADC_Keywords: QSOs ; Photometry
Keywords: reference systems - astrometry - quasars: general
Abstract:
The goal to this work is to observe a first set of 70 extragalactic
sources at optical wavelengths that could achieve the link with the
ICRF. Variations in the light curves of these targets are connected
with astrophysical processes that could produce displacements of the
optical photocenter. Such displacements, if they exist, are critical
in the framework of the link of reference systems.
Four telescope were used to observe the targets at optical
wavelengths. Two of them are located in France, one in Chile, and the
last in Australia. First observations were carried out during one year
and a half in the R and V bands. A new method of characterizing the
compactness of the targets was applied to the images obtained.
Description:
File table4 contains the name of the sources, their observation dates,
the location of the telescope used, the filter names, the magnitudes
and their corresponding uncertainties. The observations have been
carried out between 2010 and 2012.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
qsos.dat 36 47 List of studied QSOs
table4.dat 51 2636 List of observations from 2010 to 2012
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Byte-by-byte Description of file: qsos.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- QSO Target name (HHMM+DDd, B1950)
10- 11 I2 h RAh SIMBAD right ascension (J2000)
13- 14 I2 min RAm SIMBAD right ascension (J2000)
16- 20 F5.2 s RAs SIMBAD right ascension (J2000)
22 A1 --- DE- SIMBAD declination sign (J2000)
23- 24 I2 deg DEd SIMBAD declination (J2000)
26- 27 I2 arcmin DEm SIMBAD declination (J2000)
29- 32 F4.1 arcsec DEs SIMBAD declination (J2000)
34- 36 I3 --- Nvr Number of VR measurements
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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- 3 A3 --- Obs Telescope location (1)
8- 15 A8 --- QSO Target name (HHMM+DDd, B1950)
20- 29 F10.2 d JD Julian Date of observation
34 A1 --- Filter [RV] Filter used (Cousins system)
39- 43 F5.2 --- mag Magnitude in filter
48- 51 F4.2 --- e_mag Uncertainty of the magnitude determination
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Note (1): abbreviations used for the telescope location:
OHP = Observatoire de Haute Provence
OCA = Observatoire de la Cote d Azur
ESO = European Southern Observatory
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Acknowledgements:
Francois Taris, francois.taris(at)obspm.fr
(End) Francois Taris [Obs. de Paris, France], Patricia Vannier [CDS] 07-Feb-2013