1. Stochastic modeling of multiwavelength variability of the classical BL Lac object OJ 287 on timescales ranging from decades to hours
- Author
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A. Goyal, Ł. Stawarz, S. Zola, V. Marchenko, M. Soida, K. Nilsson, S. Ciprini, A. Baran, M. Ostrowski, P. J. Wiita, null Gopal-Krishna, A. Siemiginowska, M. Sobolewska, S. Jorstad, A. Marscher, M. F. Aller, H. D. Aller, T. Hovatta, D. B. Caton, D. Reichart, K. Matsumoto, K. Sadakane, K. Gazeas, M. Kidger, V. Piirola, H. Jermak, F. Alicavus, K. S. Baliyan, A. Baransky, A. Berdyugin, P. Blay, P. Boumis, D. Boyd, Y. Bufan, M. Campas Torrent, F. Campos, J. Carrillo Gómez, J. Dalessio, B. Debski, D. Dimitrov, M. Drozdz, H. Er, A. Erdem, A. Escartin Pérez, V. Fallah Ramazani, A. V. Filippenko, E. Gafton, F. Garcia, V. Godunova, F. Gómez Pinilla, M. Gopinathan, J. B. Haislip, S. Haque, J. Harmanen, R. Hudec, G. Hurst, K. M. Ivarsen, A. Joshi, M. Kagitani, N. Karaman, R. Karjalainen, N. Kaur, D. Kozieł-Wierzbowska, E. Kuligowska, T. Kundera, S. Kurowski, A. Kvammen, A. P. LaCluyze, B. C. Lee, A. Liakos, J. Lozano de Haro, J. P. Moore, M. Mugrauer, R. Naves Nogues, A. W. Neely, W. Ogloza, S. Okano, U. Pajdosz, J. C. Pandey, M. Perri, G. Poyner, J. Provencal, T. Pursimo, A. Raj, B. Rajkumar, R. Reinthal, T. Reynolds, J. Saario, S. Sadegi, T. Sakanoi, J. L. Salto González, null Sameer, A. O. Simon, M. Siwak, T. Schweyer, F. C. Soldán Alfaro, E. Sonbas, J. Strobl, L. O. Takalo, L. Tremosa Espasa, J. R. Valdes, V. V. Vasylenko, F. Verrecchia, J. R. Webb, M. Yoneda, M. Zejmo, W. Zheng, P. Zielinski, J. Janik, V. Chavushyan, I. Mohammed, C. C. Cheung, and M. Giroletti
- Subjects
ACTIVE GALACTIC NUCLEI ,Astrophysics::High Energy Astrophysical Phenomena ,OJ-287 ,FOS: Physical sciences ,Astrophysics ,individual: OJ 287 [BL Lacertae objects] ,Type (model theory) ,Astronomy & Astrophysics ,magnetic fields ,01 natural sciences ,LARGE-AREA TELESCOPE ,Radio telescope ,PERIODICITIES ,0103 physical sciences ,individual (OJ 287) [BL Lacertae objects] ,Blazar ,010303 astronomy & astrophysics ,LACERTAE OBJECTS ,acceleration of particles ,MISSION ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Science & Technology ,010308 nuclear & particles physics ,OPTICAL POLARIZATION ,Spectral density ,Astronomy and Astrophysics ,Light curve ,non-thermal [radiation mechanisms] ,BLAZARS ,13. Climate action ,Space and Planetary Science ,Colors of noise ,Physical Sciences ,active [galaxies] ,UNEQUALLY-SPACED DATA ,Astrophysics - High Energy Astrophysical Phenomena ,OJ 287 ,Noise (radio) ,BL Lac object - Abstract
We present the results of our power spectral density analysis for the BL Lac object OJ\,287, utilizing the {\it Fermi}-LAT survey at high-energy $\gamma$-rays, {\it Swift}-XRT in X-rays, several ground-based telescopes and the {\it Kepler} satellite in the optical, and radio telescopes at GHz frequencies. The light curves are modeled in terms of continuous-time auto-regressive moving average (CARMA) processes. Owing to the inclusion of the {\it Kepler} data, we were able to construct \emph{for the first time} the optical variability power spectrum of a blazar without any gaps across $\sim6$ dex in temporal frequencies. Our analysis reveals that the radio power spectra are of a colored-noise type on timescales ranging from tens of years down to months, with no evidence for breaks or other spectral features. The overall optical power spectrum is also consistent with a colored noise on the variability timescales ranging from 117 years down to hours, with no hints of any quasi-periodic oscillations. The X-ray power spectrum resembles the radio and optical power spectra on the analogous timescales ranging from tens of years down to months. Finally, the $\gamma$-ray power spectrum is noticeably different from the radio, optical, and X-ray power spectra of the source: we have detected a characteristic relaxation timescale in the {\it Fermi}-LAT data, corresponding to $\sim 150$\,days, such that on timescales longer than this, the power spectrum is consistent with uncorrelated (white) noise, while on shorter variability timescales there is correlated (colored) noise., Comment: ApJ accepted
- Published
- 2017
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