Intermittent fluctuations in physical systems

Research

We will use a central approach, the filtered Poission Process (FPP), to investigate time traces of intermittent and large-amplitude fluctuations. The FPP is a model for describing measurement time series as a superposition of uncorrelated pulses with fixed shape but randomly distributed amplitudes, arrival and duration times, or equivalently, the result of a characteristic response to pulse-like forcing. As such, it is a linear model for investigating and describing the statistical properties of non-linear systems. The model takes large-amplitude fluctuations directly into account.

We focus on the following research areas:
* near-wall turbulence in fusion energy reactors,
* cosmic dust in the interplanetary medium,
* the contribution of volcanic activity to the climate system, and
* transport of aerosol pollution in the atmosphere

Despite the large differences between these four systems, measurements from them share many statistical properties. With a common statistical modelling approach, this project will investigate important questions in all application areas:

* How do the properties of the turbulence depend on fusion energy reactor parameters
* How does the turbulence influence the interactions between the plasma and the wall and wall damage?
* How is cosmic dust distributed between the sun and the earth?
* What is the dust influx to the atmosphere of the Earth?
* What is the global temperature response to volcanic activity?
* What are the properties of the short-time structures in atmospheric aerosols?