47 citations · 282 across the 19 of their papers we have counts for
19 papers
Stochastic modeling of blob-like plasma filaments in the scrape-off layer: Time-dependent velocities and pulse stagnation
O. Paikina, J. M. Losada, A. Theodorsen +1
A stochastic model for a super-position of uncorrelated pulses with a random distribution of and correlations between amplitudes and velocities is analyzed. The pulses are assumed…
Apparent universality of spectra as an artifact of finite-size effects
M. A. Korzeniowska, A. Theodorsen, M. Rypdal +1
Power spectral density scaling with frequency as and is widely found in natural and socio-economic systems. Consequently, it has been suggested that such s…
Strongly intermittent far scrape-off layer fluctuations in Alcator C-Mod plasmas close to the empirical discharge density limit
Sajidah Ahmed, Odd Erik Garcia, Adam Q Kuang +3
Intermittent plasma fluctuations in the boundary region of the Alcator C-Mod device were comprehensively investigated using data time-series from gas puff imaging and mirror Langmu…
Stochastic modelling of blob-like plasma filaments in the scrape-off layer: Theoretical foundation
J. M. Losada, A. Theodorsen, O. E. Garcia
A stochastic model is presented for a super-position of uncorrelated pulses with a random distribution of amplitudes, sizes, velocities and arrival times. The pulses are assumed to…
Deviations from spectral Dirac comb due to semiperiodic pulses
Audun Theodorsen, Gregor Decristoforo, Odd Erik Garcia
In the frequency power spectral density, periodic oscillations appear as a Dirac comb at integer multiples of the frequency of the period. In weakly nonlinear systems or systems cl…
Numerical turbulence simulations of intermittent fluctuations in the scrape-off layer of magnetized plasmas
Gregor Decristoforo, Audun Theodorsen, John Omotani +2
Intermittent fluctuations in the boundary of magnetically confined plasmas are investigated by numerical turbulence simulations of a reduced fluid model describing the evolution of…
Comparison between mirror Langmuir probe and gas puff imaging measurements of intermittent fluctuations in the Alcator C-Mod scrape-off layer
R. Kube, A. Theodorsen, O. E. Garcia +3
Statistical properties of the scrape-off layer (SOL) plasma fluctuations are studied in ohmically heated plasmas in the Alcator C-Mod tokamak. For the first time, plasma fluctuatio…
Intermittent fluctuations due to Lorentzian pulses in turbulent thermal convection
G. Decristoforo, A. Theodorsen, O. E. Garcia
Turbulent motions due to flux-driven thermal convection is investigated by numerical simulations and stochastic modelling. Tilting of convection cells leads to the formation of she…
Scaling of shot noise processes
Audun Theodorsen
In this contribution, we investigate the scaling of the distribution of the shot noise process, its power spectral density and its time above threshold.
Reconstruction of intermittent data time series as a superposition of pulses
Sajidah Ahmed, Odd Erik Garcia, Audun Theodorsen
Fluctuations in a vast range of physical systems can be described as a superposition of uncorrelated pulses with a fixed shape, a process commonly referred to as a (generalized) sh…
Probability distribution functions for intermittent scrape-off layer plasma fluctuations
Audun Theodorsen, Odd Erik Garcia
A stochastic model for intermittent fluctuations in the scrape-off layer of magnetically confined plasmas has been constructed based on a super-position of uncorrelated pulses arri…
Intermittent electron density and temperature fluctuations and associated fluxes in the Alcator C-Mod scrape-off layer
Ralph Kube, Odd Erik Garcia, Audun Theodorsen +4
The Alcator C-Mod mirror Langmuir probe system has been used to sample data time series of fluctuating plasma parameters in the outboard mid-plane far scrape-off layer. We present…
Intermittent fluctuations in the Alcator C-Mod scrape-off layer for ohmic and high confinement mode plasmas
O. E. Garcia, R. Kube, A. Theodorsen +2
Plasma fluctuations in the scrape-off layer of the Alcator C-Mod tokamak in ohmic and high confinement modes have been analyzed using gas puff imaging data. In all cases investigat…
Level crossings and excess times due to a super-position of uncorrelated exponential pulses
Audun Theodorsen, Odd Erik Garcia
A well-known stochastic model for intermittent fluctuations in physical systems is investigated. The model is given by a super-position of uncorrelated exponential pulses, and the…
Auto-correlation function and frequency spectrum due to a super-position of uncorrelated exponential pulses
O. E. Garcia, A. Theodorsen
The auto-correlation function and the frequency power spectral density due to a super-position of uncorrelated exponential pulses are considered. These are shown to be independent…
SOL width and intermittent fluctuations in KSTAR
O. E. Garcia, R. Kube, A. Theodorsen +5
Radial profiles of the ion saturation current and its fluctuation statistics are presented from probe measurements in L-mode, neutral beam heated plasmas at the outboard mid-plane…
Statistical properties of a filtered Poisson process with additive random noise: Distributions, correlations and moment estimation
Audun Theodorsen, Odd Erik Garcia, Martin Rypdal
Filtered Poisson processes are often used as reference models for intermittent fluc- tuations in physical systems. Such a process is here extended by adding a noise term, either as…
Scrape-off layer turbulence in TCV: evidence in support of stochastic modelling
A. Theodorsen, O. E. Garcia, J. Horacek +2
Intermittent fluctuations in the TCV scrape-off layer have been investigated by analysing long Langmuir probe data time series under stationary conditions, allowing calculation of…
Fluctuation statistics in the scrape-off layer of Alcator C-Mod
Ralph Kube, Odd Erik Garcia, Audun Theodorsen +2
We study long time series of the ion saturation current and floating potential, sampled by Langmuir probes dwelled in the outboard mid-plane scrape off layer and embedded in the lo…