J/A+A/531/A123 Optical light curve of PKS 2155-304 (Kastendieck+, 2011)
Long-term optical variability of PKS 2155-304.
Kastendieck M.A., Ashley M.C.B., Horns D.
<Astron. Astrophys. 531, A123 (2011)>
=2011A&A...531A.123K 2011A&A...531A.123K
ADC_Keywords: BL Lac objects ; Photometry
Keywords: BL Lacertae objects: individual: PKS 2155-304 - methods: statistical -
galaxies: photometry - accretion, accretion disks - galaxies: jets -
black hole physics
Abstract:
The long-term optical light curve of PKS 2155-304 is assembled from
archival data as well as from so-far unpublished observations mostly
carried out with the ROTSE-III and the ASAS robotic telescopes. A
forward folding technique is used to determine the best-fit parameters
for a model of a power law with a break in the power spectral density
function (PSD). The best-fit parameters are estimated using a
maximum-likelihood method with simulated light curves in conjunction
with the Lomb-Scargle periodogram and the first-order structure
function (SF). In addition, a new approach based upon the so-called
multiple fragments variance function (MFVF) is introduced and compared
to the other methods. Simulated light curves have been used to confirm
the reliability of these methods as well as to estimate the
uncertainties of the best-fit parameters.
Description:
Optical light curve (R-band) of PKS 2155-304 measured with ROTSE.
The light curve was observed from August 24th, 2003 till October 26th,
2010 with the ROTSE-III telescope system.
ROTSE (2003PASP..115..132A 2003PASP..115..132A) does not use an R-Band filter. The R-band
magnitudes are rather cross calibrated with the magnitudes of hundreds
of reference stars. Since the optical spectrum of PKS 2155-304
deviates from a star-like spectrum the measured luminosity deviates
systematically. A cross calibration with the ATOM telescope
(2004AN....325..659H 2004AN....325..659H) revealed that the ROTSE magnitude can be
adjusted by subtracting 0.22 from the measured values:
mR=mROTSE-0.22.
Objects:
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RA (2000) DE Designation(s)
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21 58 52.1 -30 13 32 PKS 2155-304 = QSO B2155-304
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
phot.dat 30 6310 Optical light curve (R-band) of PKS 2155-304
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See also:
IX/19 : X-ray lightcurves of bright AGNs from Ginga (Hayashida+ 1998)
J/A+A/469/503 : VRIJHK observations of PKS 2155-304 (Dolcini+, 2007)
Byte-by-byte Description of file: phot.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d JD Julian Date
17- 22 F6.3 --- Rmag Apparent R-band magnitude (1)
25- 30 F6.4 --- e_Rmag 1 σ statistical uncertainty of Rmag
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Note (1): Rmag deviates systematically with ~+0.22 (see descr. above)
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Acknowledgements:
Max A. Kastendieck, max.kastendieck(at)physik.uni-hamburg.de
References:
Akerlof, C. W. et al. 2003, (2003PASP..115..132A 2003PASP..115..132A)
The ROTSE-III Robotic Telescope System
Hauser, M. et al. 2004, (2004AN....325..659H 2004AN....325..659H)
ATOM - an Automatic Telescope for Optical Monitoring
(End) M. Kastendieck [Univ. of Hamburg, Germany], P. Vannier [CDS] 01-Jul-2011