类星体3C345的光变周期特性

收集了类星体3C345光学B波段100多年来较为完备的观测数据，获得了其长期光变曲线.利用小波分析的方法对其中B波段28年的数据进行了多时间尺度分析，并用小波变换系数图展示了3C345光学B波段的爆发过程.通过研究发现了其中存在有450天，780天，1830天和3540天的近似光变周期.利用小波逆变换可以反映其光变在不同时间尺度上的演变特征，进而预测类星体3C345未来可能的光学爆发时间为2010年左右.关键词：小波分析方法光变曲线多时间尺度小波变换系数图

Analysis of the variability periodicities of quasar 3C345

This paper has collected all available optical B magnitudes of quasar 3C345 of more than 100 years, and acquired it's long-term light curve. We make a muti-time scale analysis to it's B band data with the wavelet analysis method, and get the wavelet transform coefficient plots to demonstrate the explosion process of the optical B band of 3C345. From the analysis, we have found that threr exist approximate periods of 450 d, 780 d, 1830 d and 3540 d. The inverse wavelet transform shows the light curve variability of 3C345 on different time scales, so we can predict it's possible explosion time is the year of 2010.