Period analysis for simultaneous multichannel photometric observations

The method of three stage weighted period analysis is generalized for simultaneous multichannel ob- servations. The new method is based on the phase disper- sion minimization over all channels simultaneously. The three stages in the full algorithm are phase dispersion minimization method (PDM), linear modeling (LM) and nonlinear modeling (NLM). Simple computational tests of the multichannel period analysis (MPA) are presented. We show that the method has advantages if compared with methods where single channels are analysed sepa- rately. We derive a general formula for spurious periods and demonstrate that the interpretation of peaks in the PDM spectra can be more complicated than in classical power spectra.