SUMMARY
The dynamics of the astrophysical plasmas is known to cover a large range of scales and to be strongly dominated by nonlinear interactions. Most often solar system plasmas such as the solar wind or the planetary magnetosheats are found in a turbulent state. Over the decades, in seeking ways to understand, describe and model the complex turbulent state of space plasmas, physicists have invented progressively more complex models and data analysis techniques to extract meaningful and robust measures of the turbulent state of space plasmas while the wealth of space plasma measurements has been constantly expanding.
Through this project we aim to narrow the gap between data analysis techniques dedicated to turbulence and nonlinear dynamics that have advanced to a high degree of complexity and are becoming increasingly more demanding from the point of view of programming and computer resources and the huge amount of data that is continuously being collected by present and future ESA space missions.
Our goal is to develop an advanced open-source software analysis tool – ODYN – to investigate nonlinearity, turbulence and intermittency in the Solar System plasmas from data collected by past, current and future ESA missions in the heliosphere or orbiting planets in the solar system. We take advantage of an existing database dedicated to studying turbulence and intermittency in solar system plasmas, the European FP7-project STORM database of carefully selected time series of magnetic field and plasma measurements in the solar wind at different heliodistances and in the planetary magnetosheaths to test and validate our product.
Relying on the expertize of our team members in programming, designing user-dedicated interfaces and not the least highly trained in nonlinear dynamics and turbulence in space plasmas, through this proposal we start from the conceptual design of ODYN, which sets the start level of TRL at 2. Throughout the development of ODYN we will continually test the performance and reliability of our product and we will validate the developed software package by comparing our output with results found in the scientific literature. We aim to demonstrate the functionality of our product through testing and usage of ODYN on sample data from ESA databases by invited external and independent users (i.e. not necessarily possessing programming skills or prior knowledge of the programming language chosen to complete our goal). Thus, the expected end TRL is estimated at level 5.
The end-product of our project will have great potential to speed up and enhance the scientific output of ESA space missions both launched or soon to be launched, e.g. ExoMars, Solar Orbiter, BepiColombo, Juice, thus actively and amply contributing to ESA's scientific programme.
Turbulence and nonlinear dynamics are thought to be the main drivers for plasma heating, particle acceleration and energy dissipation, thus understanding the mechanisms of such phenomena is mandatory for attaining reliable predictability of future states of the complex dynamics of the heliosphere. ODYN will contribute to the advance of our understanding in this field with clear effects on improving our ability to predict natural phenomena in space that may be harmful for satellite operation, human space-flights or even ground based instruments and infrastructure. From this point of view, we address the issues considered through ESA's programme related to Space Security through Space Situational Awareness.
Earth Observation programme can also be tackled due to the ability of ODYN of analyzing measurements provided by dedicated ESA missions such as SWARM which is set to unravel the mystery of Earth's magnetic field.
ODYN holds several distinguishable features, i.e. automatized analysis, user-customization and easy-usage, that will facilitate the interaction between national and international scientists involved in nonlinear dynamics and turbulence analysis of solar system plasmas, a collaboration that will promote the development of our national research capabilities in space science, will strengthen our national position among the experts of this scientific field at the international level and, not the least will provide a proper scientific environment for improving the quality of our national fundamental research, which constitute indeed several of the main objective of the STAR programme. In the same context, as an open-access software, ODYN can have direct impact on the continuous training of scientists with straightforward progress towards excellency not only by providing easy access to data but also to complex analysis methods. Moreover, ODYN can benefit both research institutes and universities but also agencies or even interested private parties and this paves the way towards strengthening the relation between such entities at both national and international levels.
OBJECTIVES AND METHODS
The main goal of ODYN is to provide the space plasma scientific community with an open-source software package of algorithms that implement a comprehensive collection of analysis methods as an instrument for turbulence and non-linear dynamics analysis in solar system plasmas. ODYN will be enriched with two innovative features: customizable input parameters and the possibility for automatic analysis of larger sets of data collections.
The objectives of ODYN are:
- Development of robust open-source routines for retrieving, reading, processing and visualization of experimental data recorded by space missions.
- Open-source algorithm implementations of classical and advanced analysis methods dedicated to turbulence and non-linear dynamics.
- User-customizable features and automatized open-source software package suitable for the analysis of larger collections of measurements.
The kernel of ODYN includes the following complex analysis methods for turbulence and intermittency in space plasmas:
- Power Spectral Density (PSD)
- Wavelet Transforms
- Probability Distribution Functions (PDF)
- Structure Functions (SF-K/F)
- Fractals and Multifractals (ROMA)
- Partition Function Analysis (PFMA)
- Discriminating Statistics through Mutual Information (DS-MI)