Toré Andre was awarded the 2018 Yara’s Birkeland price for his PhD thesis “Development of a miniaturized multi-Needle Langmuir Probe system for in-situ measurements of electron density and spacecraft floating potential”, for which he was awarded the degree for Philosophiae Doctor at the University of Oslo in 2017. He was supervised by professors Torfinn Lindem and Jøran Idar Moen at the Department of Physics, University of Oslo.
About Yara Birkeland price:
The price is awarded the PhD to best meets Birkelands philosophy of research. The price and presentation is focused on environment and technology and to capture interest for research and development across subject matters.
The Yara’s Birkeland price is awarded yearly alternate between physics and chemistry. The price is presented at the Birkeland Lecture at The Norwegian Academy of Science and Letters.
The winner is selected by a committee of five members including members representing Yara, Norske Fysiske Selskap, Norske Kjemiske Selskap. The committee selects the price winner based upon a PhD evaluated at a Norwegian Universety within in the last two years.
About the multi-Needle Langmuir Probe:
Tore André Bekkeng’s field of research is plasma physics of the ionosphere. The scientific exploration and technological utilization of the ionosphere and near space depends crucially on the reliability of radio communication with satellite and sounding rockets. Radio signals are sensitive to the density of free electrons in the medium they propagate through, and in the ionosphere this varies significantly both in time, on scales from years to below a second, and in space, on scales of hundreds of kilometers to below a meter. These variations significantly influence radio wave propagation. This can have significant practical consequences, e.g. for the accuracy of GPS systems. For scale lengths above a kilometer and timescales longer than a minute, the electron density profiles are successfully monitored by using incoherent scatter radars. In his work Bekkeng successfully addresses the challenge of measuring variations in the electron density on scales from a kilometer to below a meter from sounding rockets and satellites.
Bekkeng’s approach is based on an improvement of the Langmuir probe, originally introduced by Irving Langmuir in the 1920s. Such a probe works by inserting one or a number of electrodes into a plasma. By varying the electrode potentials and measuring the resulting currents, information on electron density and other plasma parameters can be extracted. The improved instrument, called a Four-Needle Langmuir Probe (4-NLP), or more generally a multi-Needle Langmuir Probe (m-NLP), allows for much better resolution in space and time for measurements of plasma turbulence. The idea for this instrument germinated in the research group in ionospheric plasma physics at the Physics Department of the University of Oslo, where Bekkeng obtained his PhD. Combining improvements in the theory of Langmuir probes with experiments and engineering developments, Bekkeng has developed the improved probe from an idea into a fully operational robust and flexible instrument. It has been successfully tested in sounding rocket experiments, obtaining valuable data, and is now operational in the Norwegian space weather satellite NorSat-1. The instrument has made it possible to obtain much more accurate and detailed information on the electron density in the ionosphere on meter scales with sampling rates above 5 kHz. Probes suitable for mass deployment in miniaturized CubeSat satellites have also been developed, and are presently being tested. The technology has been patented and is process of being commercialized.
In conclusion, Tore André Bekkengs work represent a valuable improvement in our ability to map and understand variations in the electron density of the ionosphere, and its consequences. The work is directly related both in spirit and in substance to Kristian Birkeland’s research, representing fundamental research into the physics of ionospheric phenomena with immediate potential applications to important technologies.