講演情報
[PCG18-P01]Test results of the breadboard-model ion mass spectrometer for the Comet Interceptor mission
*笠原 慧1、渡辺 瑞穂1、川島 桜也1、横田 勝一郎2、斎藤 義文3、浅村 和史3、平原 聖文4 (1.東京大学、2.大阪大学、3.宇宙科学研究所、4.名古屋大学)
Comets are pristine small bodies and thus provide key information about the solar system evolution. Remote observations by ground observatories have characterized various comets, while in-situ observations by spacecraft have brought much more detailed information on several comets. However, the direct observations by spacecraft fly-by or rendezvous have been limited to the short-period comets, which neared the sun many times in the past and thus lost some of primitive characteristics. The Comet Interceptor mission, led by ESA, aims at a long period comet or an interstellar object. JAXA will provide an ultra-small (24 U) daughter spacecraft (probe B1), whose closest approach will be less than 1,000 km, allowing the first-ever multi-spacecraft fly-by observations of a comet. Probe B1 will be equipped with three scientific instruments: (1) the Plasma Suite, which is comprised of an ion mass spectrometer and a three-axis magnetometer, (2) the Hydrogen Imager, and (3) the Narrow/wide Angle Cameras. Here we report our test results of the breadboard-model ion mass spectrometer. The mass resolution obtained in the laboratory experiment is M/dM > 30, which agrees with the numerical simulation. It enables the discrimination among carbon, nitrogen, and oxygen ions, which are major elements in cometary comae.