1. Exploring high-energy emission from the bl lacertae object s5 0716+714 with the fermi large area telescope
- Author
-
Shen-Bang Yang, R. J. Britto, Guo-Mei Zhang, Bindu Rani, Wei Zeng, Stefan Larsson, T. Wen, D. J. Thompson, Xiong-Fei Geng, Wen Hu, Ben-Zhong Dai, and Gang Cao
- Subjects
Physics ,Range (particle radiation) ,010504 meteorology & atmospheric sciences ,Flux ,Astronomy and Astrophysics ,Astrophysics ,Light curve ,01 natural sciences ,Spectral line ,Astrophysical jet ,Astronomi, astrofysik och kosmologi ,Space and Planetary Science ,0103 physical sciences ,Astronomy, Astrophysics and Cosmology ,Blazar ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Fermi Gamma-ray Space Telescope ,BL Lac object - Abstract
We present the results of an extensive γ-ray data analysis of the emission from the blazar S5 0716+714 with the primary motivation to study its temporal and spectral variability behavior. In this work, we extract a 10 days binned γ-ray light curve from 2008 August 4 to 2016 April 27 in the energy range of 0.1–300 GeV and identify six outburst periods with peak flux of >4 × 10−7 ph cm−2 s−1 from this highly variable source. The brightest flares are identified by zooming in these outburst periods to 1 day binning and using the Bayesian Blocks algorithm. The fastest variability timescale is found to be 1.5 ± 0.3 hr at MJD 57128.01 ± 0.01 with a peak flux above 100 MeV of (26.8 ± 6.9) × 10−7 ph cm−2 s−1. No hint of periodic modulations has been detected for the light curve of S5 0716+714. During the outburst phases, the γ-ray spectrum shows an obvious spectral break with a break energy between 0.93 and 6.90 GeV energies, which may be caused by an intrinsic break in the energy distribution of radiating particles. The five highest-energy photons, with E > 100 GeV, imply that the high-energy emission from this source may originate from a moving emission region in a helical path upstream in the jet. The spectral behavior and temporal characteristics of the individual flares indicate that the location of the emission region lies in the sub-parsec scale (r γ
- Published
- 2020