your ID: 0247 First Name: Dimitrios Last Name: Emmanoulopoulos Affiliation: ZAH, Landessternwarte Title: Higher Order Time Series Analysis of Mrk 421 Authors: D.Emmanoulopoulos, S.J.Wagner Topic: 3 Session: poster Abstract: We have analyzed all the archival RXTE data of Mrk 421 taken from the PCA. After homogenized them we performed a higher-order time series analysis in order to characterize the dynamical properties of the emission mechanism. We find a strong indication of genuine non-stationarity in the radiation process.