| Autor: |
Ryan, James L., Siemiginowska, Aneta, Sobolewska, Malgosia, Grindlay, Jonathan |
| Rok vydání: |
2019 |
| Předmět: |
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| Druh dokumentu: |
Working Paper |
| DOI: |
10.3847/1538-4357/ab426a |
| Popis: |
Characteristic variability timescales in blazar gamma-ray light curves can provide insight into the physical processes responsible for the gamma-ray variability. The power spectral density (PSD) is capable of revealing such timescales, which may appear as breaks or periodicities. Continuous-time autoregressive moving-average (CARMA) models can be used to accurately estimate a light curve's PSD. Through a lightcurve simulation study, we develop a methodology to identify PSD breaks using CARMA models. Using this methodology, we study the gamma-ray light curves of 13 bright blazars observed with the Fermi Large Area Telescope in the 0.1-300 GeV band over 9.5 years. We present the blazar gamma-ray PSDs, which provide evidence for low-frequency breaks on timescales ~1 year in four sources, and an additional high-frequency break on a timescale ~9 days in one source. |
| Databáze: |
arXiv |
| Externí odkaz: |
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