Experimental Physics: Plasmas

Plasma experiments usually do not allow true interaction between the trainees and the equipment because they must be conducted under vacuum, with expensive devices and usually the time-to-practice is too long. So, there is no effective gain in leading the trainees to interact directly with the equipment as most of it is automated and already controlled by digital means. On the other hand, plasma experiments are very rich in terms of data analysis and their physical interpretation, being a must for acquiring the necessary sensibility to work in this field. In this course you will learn and perform two remote-controlled experiments on how to measure the most important plasma parameters, namely their density and temperature, by intrusive and non-intrusive methods. Among the data analysis techniques introduced, two less common data fittings are used, one with a piecewise function fitting and another based on a RF spectrum interpretation.

Matrícula Encerrada

General description

The course consists of two main practical topics after an introduction on plasma diagnostics related to intrusive and non-intrusive diagnostics in plasma physics each one anchored on a remote laboratory. The introduction to the fundamentals of plasma physics and their diagnostics will consist on a brief overview as the course is imminently practical. The remote controlled laboratories will take place over the FREE platform where you must conduct and analyze data from (i) a Langmuir probe and an (ii) electromagnetic resonant cavity experiments. Such experiments are fully automated but configurable by the user. Emphasis will be given to special techniques on data analysis, on how to supersede the noise, and their interpretation. This course is unique in the sense that, to our knowledge, it is the very first MOOC where your experimental data is automatically analyzed by our FREE framework and your calculations automatically checked based on that data. You'll receive instant feedback on your performance.

Target audience

The course is targeted for graduate students in physics or engineering interested in plasma physics but can be followed by undergraduate students with previous knowledge of electromagnetism and experimental physics.

Main goals

When concluding this course you are expected to know how to measure some basic plasma parameters and master the necessary techniques of data analysis to interpret the raw data coming from the experiments. As data taken from plasma diagnostics can be quite noisy, another important outcome is to develop a critical view on the quality of the information retained.

Prerequisites

You should have some background in electromagnetism and experimental physics; knowledge of plasma physics may be useful but is not mandatory.

Fundamentals of plasma diagnostics;
Remote controlled laboratories in plasma physics;
Data analysis ;
Noise suppression on data processing;
Interpretation of a Langmuir probe I(V) characteristic;
Behaviour and influence of the plasma dispersion relation in a resonant cavity.

Organization and Duration

This course is organized in three main topics, and each topic will take one week. The topics include videos that will be complemented with support notes. The course also includes a discussion forum in which the participants can ask questions to the tutors and share ideas with the peers.

Enrollment opens June, 3rd

Assessment and Certification

The course will be considered passed if the final score is 60% or more of the maximum possible graded activities. The final grade has two components: (i) some exercises that are mostly follow-up quizzes and (ii) the data analysis of the two remote controlled plasma experiments. You have 2 attempts to answer most questions. The experiment’s assessment is done on the Framework for Remote Experiments in Education (FREE) where you will be asked for important measurements of your work. The course has the unique feature of automatically analyzing your specific data, giving a direct assessment on your results.

Tutors

Horácio Fernandes

Associate professor at Técnico and researcher at IPFN, where he coordinates the activities in the tokamak ISTTOK. In 1999 he created the elab, the first remote laboratory at Técnico and one of the few in the world designed for education, with free access to about 20 experiments.

His scientific interests cover engineering, diagnostics and real-time operation of nuclear fusion devices. He regularly participates in science outreach activities. He was a member of the Technical Advisor Panel at F4E (the European agency at ITER) and is a research coordinator at IAEA.

Carlos Silva

Senior Researcher at Técnico in IPFN, with research focused on edge physics, multi-scale turbulent transport and diagnostic development in fusion devices. The work is performed in devices such as ISTTOK (Portugal), TJ-II (Spain), AUG (Germany) and JET (UK), where I regularly participate in experimental campaigns. His research methodology combines data analysis with diagnostic development aiming at contributing to the understanding of turbulent transport in fusion devices. Carlos Garcia Silva contributes to the support of the Master and Ph.D. programs at IST and is responsible for the Master course on Plasma Diagnostic Techniques and the Ph.D. course on Diagnostic Methods for Plasmas since 2013.

Pedro Rossa

Técnico’s undergraduate student in MEFT, has developed work on the installation of remote controlled experiments, some of them for plasma diagnostics. He was part of the team that created the Framework for Remote Experiments in Education (FREE), turning elab into a web application.

João Nuno Silva

João Nuno Silva holds a Ph.D. degree in computer science. He is currently an Assistant Professor with the Department of Electrical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Portugal, and researcher at INESC-ID (Instituto de Engenharia de Sistemas e Computadores: Investigação e Desenvolvimento em Lisboa). He has been doing research and development in parallel and distributed systems, for many years, with a focus on mobile computing, and web architectures and technologies.

José Lopes

Master's student of Electrical and Computer Engineering at Instituto Superior Técnico. Contributed in the development of quizzes and deployment of remote controlled experiments to the Framework for Remote Experiments in Education (FREE). Interested in AI as a tool to solve complex problems, additive manufacturing processes and free and open-source software (FOSS).

FAQs

Do I need special software to follow the course?

Although the course can be followed on-line with an usual browser, it is better to use a personal computer for an optimal experience, avoiding cell-phones. The data can be analyzed on any spreadsheet but a software system or numerical framework with built-in libraries for technical computing that allow statistics, data manipulation, series analysis, and various types of data plotting is recommended (such as Mathematica, Origin, Fitteia, Python, Dadisp, Matlab, etc.)

FREE and the feX-Plasmas (MOOC) accounts have to be the same?

On the FREE framework only Google or Fenix (IST LMS platform) accounts can be used. Conversely, at Open edX fex-Plasmas any account created specifically on the IST MOOC platform can be utilized. Nevertheless, even using a common account on FREE and IST Open edX platform, access to the data generated inside the MOOC platform can only be reached by execution number on FREE; so please have your executions manually registered in case you want to access that data later outside feX-Plasmas.

Are the plasma experiments available freely 24x7?

The plasma experiments offered by the advanced laboratory in elab are available 24x7 but a special care has to be taken in analyzing the data: effectively there are restrictions on the gasses buffering stage which are refilled periodically but under high usage their consumption can lead to empty buffers and the initial atmosphere for the plasma creation may be fake.

Bibliography

Most resources are available on the elab wiki’s project. Nevertheless we recommend some important bibliography in this field:

I. H. Hutchinson, "Principles of Plasma Diagnostics", 2nd edition, Cambridge, 2002.
John R. Taylor, “An Introduction to Error Analysis: The Study of Uncertainties in Physical Measurements”, University Science Books; 2nd edition (August 1, 1996)
V. Thomsen. “Precision and The Terminology of Measurement”. The Physics Teacher, Vol. 35, pp.15-17, Jan. 1997.

The following course and its contents are licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Técnico Lisboa - MOOC: feX_plasmas
Experimental Physics: Plasmas