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We study stochastic nature of electrical discharge current fluctuations. Using Fourier-Detrended Fluctuations Analysis, sinusoidal trend and its noise are extracted from data set and consequently cleaned data will be retrieved. We mainly focus on the Markov property of fluctuations in the plasma fluid and utilize a set of data to construct a simple stochastic equation which governs the evolution of discharge current fluctuations. The Markov time scale over which data set behaves as a Markov chain will be determined. This time scale is an increasing and monotonic function versus discharge current intensity. Using the computed values of Kramers-Moyal coefficients, we formulate corresponding Fokker-Planck and Langevin equations. Drift and diffusion coefficients regarded to the deterministic and stochastic parts of Langevin equation decrease as discharge current intensity increases. It is due to the domination of direct ionization instead of step ionization.
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