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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
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). 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) 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: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 10 01 21.0 +55 53 57 Q0957+561 = Name twin quasar ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
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)
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
Bytes Format Units Label Explanations
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
Acknowledgements: Luis J. Goicoechea, luis.goicoechea(at)unican.es
(End) L. Goicoechea [Univ. de Cantabria, Spain], P. Vannier [CDS] 20-Feb-2012
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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