Direct measurements of two-way wave-particle energy transfer in a collisionless space plasma

N. Kitamura, M. Kitahara, M. Shoji, Y. Miyoshi, H. Hasegawa, S. Nakamura, Y. Katoh, Y. Saito, S. Yokota, D. J. Gershman, A. F. Vinas, B. L. Giles, T. E. Moore, W. R. Paterson, C. J. Pollock, C. T. Russell, R. J. Strangeway, S. A. Fuselier, J. L. Burch

Research output: Contribution to journalArticlepeer-review

26 Citations (Scopus)


Particle acceleration by plasma waves and spontaneous wave generation are fundamental energy and momentum exchange processes in collisionless plasmas. Such wave-particle interactions occur ubiquitously in space. We present ultrafast measurements in Earth’s magnetosphere by the Magnetospheric Multiscale spacecraft that enabled quantitative evaluation of energy transfer in interactions associated with electromagnetic ion cyclotron waves. The observed ion distributions are not symmetric around the magnetic field direction but are in phase with the plasma wave fields. The wave-ion phase relations demonstrate that a cyclotron resonance transferred energy from hot protons to waves, which in turn nonresonantly accelerated cold He+ to energies up to ~2 kilo–electron volts. These observations provide direct quantitative evidence for collisionless energy transfer in plasmas between distinct particle populations via wave-particle interactions.

Original languageEnglish
Pages (from-to)1000-1003
Number of pages4
Issue number6406
Publication statusPublished - 2018 Sep 7

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Direct measurements of two-way wave-particle energy transfer in a collisionless space plasma'. Together they form a unique fingerprint.

Cite this