Optical/NIR Quasi-Periodic Oscillations of the Blazar PKS 0537-441 with the Weighted Wavelet Z-Transform Technique

We present the integrated R- and J-band light curves obtained by combining the Rapid Eye Mount (REM) and Small Moderate Aperture Research Telescope System (SMARTS) data and the corresponding color indices of PKS 0537-441 in 2004-2015. By means of the weighted wavelet Z-transform (WWZ), there is evidence for quasi-periodic oscillations (QPOs) of 148 d and 429 d in R-band light curve, 150 d and 416 d in J-band light curve and 492 d in color indices curve. The inconsistency of QPOs in color indices and light curves probably reveals the existence of the multiple color behavior, although a moderate redder-when-bright trend has been detected in long-term timescales.