Study on Particle Temperatures and Defects in Self-Organized Coulomb Crystals

2015 Fiscal Year Final Research Report

• Project/Area Number: 25610174
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Plasma science
• Research Institution: Japan Aerospace EXploration Agency
• Principal Investigator: ADACHI Satoshi 国立研究開発法人宇宙航空研究開発機構, 宇宙科学研究所, 准教授 (80358746)
• Co-Investigator(Renkei-kenkyūsha): OKADA Junpei 東北大学, 金属材料研究所, 准教授 (90373282)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 微粒子プラズマ / クーロン結晶 / 粒子温度 / イオン温度

Outline of Final Research Achievements

From velocity distribution of particle motion and wave propagation in the Coulomb crystal, it is found that particle temperature is several times higher than the room temperature. From the dispersion relation of the dust lattice wave (DLW), the ion temperature is obtained and is close to the room temperature. In order to investigate power sources of particle acceleration, the ion energy is estimated by considering ion acceleration caused by the negative potential on the particle surface. The potential profile is obtained by solving the Poisson equation. Thus the ion energy is obtained to be several times higher than the room temperature. Although the electron energy is still higher than the ion energy, the ion energy should be an important power source. A new plasma chamber is developed to suppress a void formation. The shape of Coulomb cloud suggests that the potential profile is much flat as expected. This result will be used for development of a next-generation apparatus.

Free Research Field

プラズマ物理、結晶成長工学