Revisiting Quasi-periodic Modulation in γ -Ray Blazar PKS 2155-304 with Fermi Pass 8 Data

Journal Article · Wed Feb 01 00:00:00 EST 2017 · Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/835/2/260· OSTI ID:22663926

Zhang, Peng-fei; Liao, Neng-hui ^[1]; Yan, Da-hai; Wang, Jian-cheng ^[2]

---

1. Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)
2. Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011 (China)

We examine the gamma-ray quasi-periodic variability of PKS 2155-304 with the latest publicly available Fermi -LAT Pass 8 data, which covers the years from 2008 August to 2016 October. We produce the light curves in two ways: the exposure-weighted aperture photometry and the maximum likelihood optimization. The light curves are then analyzed by using Lomb-Scargle Periodogram (LSP) and Weighted Wavelet Z-transform, and the results reveal a significant quasi-periodicity with a period of 1.74±0.13 years and a significance of ∼4.9 σ . The constraint of multifrequencies quasi-periodic variabilities on blazar emission model is discussed.

• OSTI ID: 22663926
• Journal Information: Astrophysical Journal, Vol. 835, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
APERTURES
BL LACERTAE OBJECTS
COSMIC GAMMA SOURCES
EMISSION
GALAXIES
LIMITING VALUES
MODULATION
PERIODICITY
PHOTOMETRY
VISIBLE RADIATION