Experimental approaches to reveal formation process of cosmic dust taken into account singular properties in mesoscale

2014 Fiscal Year Final Research Report

• Project/Area Number: 24684033
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Solid earth and planetary physics
• Research Institution: Hokkaido University (2014); Tohoku University (2012-2013)
• Principal Investigator: KIMURA Yuki 北海道大学, 低温科学研究所, 准教授 (50449542)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 結晶成長 / ナノ粒子 / 宇宙ダスト / 干渉法 / 核生成

Outline of Final Research Achievements

We succeeded to measure the temperature and concentration of a vapor at the moments of nucleation using a specially designed interferometer. Surface free energy and sticking probability of nanoparticles can be determined based on nucleation theories. As the result, it has been found that extremely high supersaturation of ten to the power of 4th to 14th has been required and for homogeneous nucleation and then the sticking probability is as small as 0.01%. In addition, the nuclei form as a liquid phase and crystallize as temperature drops and, therefore, structure of nuclei does not determine at the time of initial nucleation.

Free Research Field

ナノ領域科学