J/A+A/540/A132 Optical follow-up of Q0957+561 in 2005-2010 (Shalyapin+, 2012)
A 5.5-year robotic optical monitoring of Q0957+561: substructure in a non-local
cD galaxy.
Shalyapin V.N., Goicoechea L.J., Gil-Merino R.
<Astron. Astrophys. 540, A132 (2012)>
=2012A&A...540A.132S 2012A&A...540A.132S
ADC_Keywords: QSOs ; Gravitational lensing ; Photometry, SDSS
Keywords: gravitational lensing: strong - quasars: individual: Q0957+561 -
galaxies: elliptical and lenticular, cD - black hole physics
Description:
The optical variability database of the two images (A and B) of the
gravitationally lensed quasar Q0957+561 is based on frames taken with
the Liverpool Robotic Telescope in the 2005-2010 period, as part of
the Liverpool Quasar Lens Monitoring (LQLM) project (Goicoechea et al.
2010AdAst2010E..29G 2010AdAst2010E..29G). A crowded-field photometry pipeline produced
instrumental fluxes of both quasar images, and only frames with
signal-to-noise ratio above 80 over Q0957+561A were passed through a
transformation pipeline. This pipeline transformed instrumental
magnitudes into SDSS magnitudes (the calibration-correction scheme is
described in Appendix A of Shalyapin et al. (2008A&A...492..401S 2008A&A...492..401S) and
the main text of the paper). We also turned SDSS magnitudes into
physical fluxes using suitable conversion equations (SDSS Photometric
Flux Calibration 2007,
http://www.sdss.org/dr7/algorithms/fluxcal.html). Table 1 contains
g-band fluxes for 357 different nights, while Table 2 includes r-band
fluxes for 371 observation nights.
Objects:
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RA (2000) DE Designation(s)
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10 01 21.0 +55 53 57 Q0957+561 = Name twin quasar
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 49 357 Fluxes in the g band (468.6nm)
table2.dat 49 371 Fluxes in the r band (616.5nm)
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See also:
J/ApJ/510/64 : Radio time delay of gravitational lens 0957+561 (Haarsma+, 1999)
Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 9 F9.3 d MJD Modified Julian Date
14- 19 F6.4 mJy SA Flux of Q0957+561A
24- 29 F6.4 mJy e_SA Error in the flux of Q0957+561A
34- 39 F6.4 mJy SB Flux of Q0957+561B
44- 49 F6.4 mJy e_SB Error in the flux of Q0957+561B
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Acknowledgements:
Luis J. Goicoechea, luis.goicoechea(at)unican.es
(End) L. Goicoechea [Univ. de Cantabria, Spain], P. Vannier [CDS] 20-Feb-2012