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Kepler observations of rapid optical variability in the BL Lac object W2R1926+42

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journal contribution
posted on 10.02.2016 by R. Edelson, R. Mushotzky, Simon Allan Vaughan, J. Scargle, P. Gandhi, M. Malkan, W. Baumgartner
We present the first Kepler monitoring of a strongly variable BL Lac, W2R1926+42. The light curve covers 181 days with ~0.2% errors, 30 minute sampling and >90% duty cycle, showing numerous delta I/I > 25% flares over timescales as short as a day. The flux distribution is highly skewed and non-Gaussian. The variability shows a strong rms-flux correlation with the clearest evidence to date for non-linearity in this relation. We introduce a method to measure periodograms from the discrete autocorrelation function, an approach that may be well-suited to a wide range of Kepler data. The periodogram is not consistent with a simple power-law, but shows a flattening at frequencies below 7x10-5 Hz. Simple models of the power spectrum, such as a broken power law, do not produce acceptable fits, indicating that the Kepler blazar light curve requires more sophisticated mathematical and physical descriptions than currently in use.

History

Citation

Astrophysical Journal, 2013, 766 (1), 16

Author affiliation

/Organisation/COLLEGE OF SCIENCE AND ENGINEERING/Department of Physics and Astronomy

Version

VoR (Version of Record)

Published in

Astrophysical Journal

Publisher

IOP Publishing, American Astronomical Society

issn

0004-637X

eissn

1538-4357

Acceptance date

01/02/2013

Copyright date

2013

Available date

10/02/2016

Publisher version

http://iopscience.iop.org/article/10.1088/0004-637X/766/1/16/meta

Language

en

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