Study on Long-Period Variability Analysis Methods of Quasars

This paper first introduces four methods for analyzing long-period variability of quasars, then uses a simulated periodic signal y=sinθ to test four methods. The analysis results show:(1) When the number of data points sampled by the celestial body is relatively small to a certain value, the analysis results of Jurkevich method, DCDFT method, DCF method and PSD method are different. After getting the shortest continuous data point, the analysis result of Jurkevich method is probably the most accurate and reliable among the four methods, and the calculation method is simple and practical. (2) The best parameters of the Jurkevich analysis method are obtained, and the best results are when m=9. (3) Using the Jurkevich method with m=9 to analyze the variability of 3C 279 is about (2.81±0.54) years and the variability of 3C 454.3 is about 457d.