Abstract
Flux density variations of the extragalactic radio source OJ 287 are studied by applying the wavelet and the singular spectrum methods to the long-term monitoring data at 14.5, 8.0 and 4.8 GHz acquired at the University of Michigan Radio Astronomy Observatory during 40 years. This monitoring significantly supplements the episodic VLBI data. The wavelet analysis at all three frequencies revealed the presence of quasiperiods within the intervals 6.0–7.4 and 1.2–1.8 years. The singular spectrum analysis revealed the presence of quasiperiods within the intervals 6–10 and 1.6–4.0 years. For each quasiperiod the time interval of its existence was determined.
REFERENCES
Alexandrov Th., Golyandina N. 2004, Exponenta Pro, 3, 5410.5802/aif.2085Search in Google Scholar
Aller H. D., Aller M. F., Latimer G. E., Hodge P. E. 1985, ApJS, 59, 51310.1086/191083Search in Google Scholar
Blandford R. D., Königl A. 1979, ApJ, 232, 3410.1086/157262Search in Google Scholar
Chistyakova A. A., Shamsha B. V. 2011, Radioelectronic and Computer Systems, 4, 105Search in Google Scholar
Cooley J. W., Lewis P., Welch P. 1969, IEEE Trans. on Education, 12, 110.1109/TE.1969.4320436Search in Google Scholar
Donskykh G. I., Ryabov M. I., Sukharev A. L., Aller M. F. 2015, Odessa Astronomical Publications, 28(2), 21710.18524/1810-4215.2015.28.71008Search in Google Scholar
Golyandina N. E. 2004, The Caterpillar-SSA Method: Time Series Analysis, St. Petersburg State University, p. 74Search in Google Scholar
Golyandina N., Shlemov A. 2015, Statistics and its Interface, 8, 27710.4310/SII.2015.v8.n3.a3Search in Google Scholar
Hardee P. E. 2000, ApJ, 533, 17610.1086/308656Search in Google Scholar
Hovatta T., Lehto H. J., Tornikoski M. 2008, A&A, 488, 89710.1051/0004-6361:200810200Search in Google Scholar
Hughes P. A., Aller H. D., Aller M. F. 1998, ApJ, 503, 66210.1086/306014Search in Google Scholar
Marscher A. P., Gear W. K. 1985, ApJ., 298, 11410.1086/163592Search in Google Scholar
Mignone A., Rossi P., Bodo G., Ferrari A., Massaglia S. 2010, MNRAS, 402, 710.1111/j.1365-2966.2009.15642.xSearch in Google Scholar
Parker M. L., Fabian A. C., Matt G. et al. 2014, MNRAS, 447, 7210.1093/mnras/stu2424Search in Google Scholar
Polikar R. 2001, http://users.rowan.edu/polikar/WAVELETS/WTutorial.htmlSearch in Google Scholar
Sillanpää A., Haarala S., Valtonen M.J., Sundelius, B., Byrd G. G. 1988, ApJ, 325, 62810.1086/166033Search in Google Scholar
Stickel M., Fried W., Kühr H. 1989, A&AS, 80, 10310.1111/j.1600-0404.1989.tb01767.xSearch in Google Scholar
Torrence C., Compo G. P. 1998, Bull. American Meteorological Soc., 79, 6110.1175/1520-0477(1998)079<0061:APGTWA>2.0.CO;2Search in Google Scholar
Valtonen M. J., Lehto H. J. 1997, ApJ, 481, L510.1086/310642Search in Google Scholar
Valtonen M., Pihajoki P. 2013, A&A, 557, A2810.1051/0004-6361/201321754Search in Google Scholar
Valtonen M. J., Lehto H. J., Nilsson K. et al. 2008, Nature, 452, 85110.1038/nature06896Search in Google Scholar
Van den Berg J. C. (ed.) 2004, Wavelets in Physics, Cambridge, Cambridge University PressSearch in Google Scholar
© 2016 Ganna Donskykh, published by De Gruyter Open
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.