Professor Masashi Koji, Specially Appointed Assistant Professor, Institute for Space-Earth Environmental Research, Nagoya University, is the first in the world to collaborate with the Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA). We have demonstrated the energy transport of particles via plasma waves.
Outer space is not a perfect vacuum, but is filled with charged particles called plasma, but at a distance of thousands to tens of thousands of kilometers from the earth, the density is very low and the charged particles hardly collide with each other.However, around the earth, the existence of electrons with sufficient energy to make the aurora shine and high-energy particles that damage satellites are known.It remains a mystery how charged particles are accelerated to higher energies in the non-collision state.
This time, the group analyzed observation data centered on the low-energy ion measuring device mounted on the MMS satellite formation of NASA in the United States, and found different plasma particle groups (hydrogen ions and helium ions) in outer space near the earth. We succeeded in directly measuring the energy transport rate by capturing the site where energy is transported via plasma waves without collision.
It is the world's first achievement to demonstrate that energy transport occurs between different plasmas via plasma waves, and in the future, other types of plasma waves and the process of energy exchange with plasma will be directly and detailed. It is expected that it can be demonstrated by observation.
This achievement was published in the American scientific journal "Science" published on September 2018, 9.
Paper information:[Science] Direct measurements of two-way wave-particle energy transfer in a collisionless space plasma