Abstract
One of the remarkable features of blazars is violent variability over a wide wavelength range. The variation mechanism causing the observed complex behavior is still under debate. The variability timescales range from less than a day to decades. Variation on timescales less than a day is known as “microvariability.” Such short-term variations can provide insights regarding the origin of the variability after they are distinguished from longer-term variational components. We select about 195 microvariability events from the continuous light curve of blazar W2R 1926+42 with 1-min time resolution obtained by the Kepler spacecraft, and estimate the timescale and amplitude of each event. The rise and decay timescales of the events reveal random variations over short timescales less than a day, but they indicate systematic variations on timescales longer than several days. This result implies that the events are not independent, but rather mutually correlated.
Highlights
Blazars have relativistic jets whose axes are nearly aligned to the line of sight [1,2]
We study the time variation of the characteristic timescales estimated from the power spectrum density (PSD) in each epoch of the light curve, and compare these characteristic timescales with the doubling times of the rise and decay phases in the micro-variation events
The blazar W2R 1926+42 exhibits violent variability with timescales less than one day, which is known as microvariability
Summary
Blazars have relativistic jets whose axes are nearly aligned to the line of sight [1,2]. Variability with timescale of less than one day, termed “microvariability” Such microvariability has been reported over wide ranges of wavelengths from radio [4] to optical [5,6], X-ray [3], GeV, and. It is not easy to extract detailed features of flare-like variations in the γ-ray band, because the time required to measure the γ-ray flux with Fermi and AGILE is usually longer than 3 h, since the number of detected photons is limited. Galaxies 2017, 5, 13 photon statistics is needed to extract the general features of microvariability in an effort to understand the underlying physics of relativistic jets. Edelson et al [12] reported numerous flares on timescales as short as 1 day in the Kepler light curve with 30-min time sampling in Quarters 11 and 12 of the Kepler mission. Continuous optical monitoring of W2R 1926+42 with denser (1 min) time sampling by Kepler [13] in Quarter 14 detected considerable microvariability of the flux
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
