太陽系科学研究系

齋藤 義文

サイトウ ヨシフミ  (Yoshifumi Saito)

基本情報

所属
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 太陽系科学研究系 教授
学位
修士(理学)(1991年3月 京都大学)
博士(理学)(1995年2月 東京大学)

連絡先
saitostp.isas.jaxa.jp
研究者番号
30260011
J-GLOBAL ID
200901006495017695
researchmap会員ID
1000174746

主要な論文

 411
  • Yoshifumi Saito, Dominique Delcourt, Masafumi Hirahara, Stas Barabash, Nicolas André, Takeshi Takashima, Kazushi Asamura, Shoichiro Yokota, Martin Wieser, Masaki N. Nishino, Mitsuo Oka, Yoshifumi Futaana, Yuki Harada, Jean André Sauvaud, Philippe Louarn, Benoit Lavraud, Vincent Génot, Christian Mazelle, Iannis Dandouras, Christian Jacquey, Claude Aoustin, Alain Barthe, Alexandre Cadu, Andréi Fedorov, Anne Marie Frezoul, Catherine Garat, Eric Le Comte, Qiu Mei Lee, Jean Louis Médale, David Moirin, Emmanuel Penou, Mathieu Petiot, Guy Peyre, Jean Rouzaud, Henry Claude Séran, Zdenĕk Nĕmec̆ek, Jana S̆afránková, Maria Federica Marcucci, Roberto Bruno, Giuseppe Consolini, Wataru Miyake, Iku Shinohara, Hiroshi Hasegawa, Kanako Seki, Andrew J. Coates, Frédéric Leblanc, Christophe Verdeil, Bruno Katra, Dominique Fontaine, Jean Marie Illiano, Jean Jacques Berthelier, Jean Denis Techer, Markus Fraenz, Henning Fischer, Norbert Krupp, Joachim Woch, Ulrich Bührke, Björn Fiethe, Harald Michalik, Haruhisa Matsumoto, Tomoki Yanagimachi, Yoshizumi Miyoshi, Takefumi Mitani, Manabu Shimoyama, Qiugang Zong, Peter Wurz, Herman Andersson, Stefan Karlsson, Mats Holmström, Yoichi Kazama, Wing Huen Ip, Masahiro Hoshino, Masaki Fujimoto, Naoki Terada, Kunihiro Keika
    Space Science Reviews 217(5) 2021年8月  査読有り筆頭著者責任著者
    BepiColombo Mio (previously called MMO: Mercury Magnetospheric Orbiter) was successfully launched by Ariane 5 from Kourou, French Guiana on October 20, 2018. The Mercury Plasma/Particle Experiment (MPPE) is a comprehensive instrument package onboard Mio spacecraft used for plasma, high-energy particle and energetic neutral atom measurements. It consists of seven sensors including two Mercury Electron Analyzers (MEA1 and MEA2), Mercury Ion Analyzer (MIA), Mass Spectrum Analyzer (MSA), High Energy Particle instrument for electron (HEP-ele), High Energy Particle instrument for ion (HEP-ion), and Energetic Neutrals Analyzer (ENA). Significant efforts were made pre-flight to calibrate all of the MPPE sensors at the appropriate facilities on the ground. High voltage commissioning of MPPE analyzers was successfully performed between June and August 2019 and in February 2020 following the completion of the low voltage commissioning in November 2018. Although all of the MPPE analyzers are now ready to begin observation, the full service performance has been delayed until Mio’s arrival at Mercury. Most of the fields of view (FOVs) of the MPPE analyzers are blocked by the thermal shield surrounding the Mio spacecraft during the cruising phase. Together with other instruments on Mio including Magnetic Field Investigation (MGF) and Plasma Wave Investigation (PWI) that measure plasma field parameters, MPPE will contribute to the comprehensive understanding of the plasma environment around Mercury when BepiColombo/Mio begins observation after arriving at the planet Mercury in December 2025.
  • Yoshifumi Saito, Shoichiro Yokota, Kazushi Asamura, Amanda Krieger
    Journal of Geophysical Research: Space Physics 122(2) 1816-1830 2017年2月1日  査読有り
    ©2017. American Geophysical Union. All Rights Reserved. The time resolution of low-energy charged particle measurements is becoming higher and higher. In order to realize high time resolution measurements, a 1-D circular delay line anode has been developed as a high-speed microchannel plate (MCP) anode. The maximum count rate of the 1-D circular delay line anode is around 1 × 107/s/360°, which is much higher than the widely used resistive anode, whose maximum count rate is around 1 × 106/s/360°. In order to achieve much higher speeds, an MCP anode with application-specific integrated circuit (ASIC) has been developed. We have decided to adopt an anode configuration in which a discrete anode is formed on a ceramic substrate, and a bare ASIC chip is installed on the back of the ceramic. It has been found that the anode can detect at a high count rate of 2 × 108/s/360°. Developments in both delay line and discrete anodes, as well as readout electronics, will be reviewed.
  • Yoshifumi Saito, Masaki N. Nishino, Masaki Fujimoto, Tadateru Yamamoto, Shoichiro Yokota, Hideo Tsunakawa, Hidetoshi Shibuya, Masaki Matsushima, Hisayoshi Shimizu, Futoshi Takahashi
    EARTH PLANETS AND SPACE 64(2) 83-92 2012年  査読有り
    At similar to 25 km altitude over magnetic anomalies on the Moon, the deceleration of the solar wind ions, acceleration of the solar wind electrons parallel to the magnetic field, and heating of the ions reflected by magnetic anomalies were simultaneously observed by MAP-PACE on Kaguya. Deceleration of the solar wind ions was observed for two major solar wind ion compositions: protons and alpha particles. Deceleration of the solar wind had the same Delta E/q (Delta E: deceleration energy, q: charge) for both protons and alpha particles. In addition, the acceleration energy of the electrons was almost the same as the deceleration energy of the ions. This indicates the existence of an anti-moonward electric field over the magnetic anomaly above the altitude of Kaguya. The reflected ions were observed in a much larger area than the area where magnetic field enhancement was observed. These reflected ions had a higher temperature and lower bulk velocity than the incident solar wind ions. This suggests the existence of a non-adiabatic dissipative interaction between solar wind ions and lunar magnetic anomalies below Kaguya.
  • Yoshifumi Saito, Shoichiro Yokota, Kazushi Asamura, Takaaki Tanaka, Masaki N. Nishino, Tadateru Yamamoto, Yuta Terakawa, Masaki Fujimoto, Hiroshi Hasegawa, Hajime Hayakawa, Masafumi Hirahara, Masahiro Hoshino, Shinobu Machida, Toshifumi Mukai, Tsugunobu Nagai, Tsutomu Nagatsuma, Tomoko Nakagawa, Masato Nakamura, Koh-ichiro Oyama, Eiichi Sagawa, Susumu Sasaki, Kanako Seki, Iku Shinohara, Toshio Terasawa, Hideo Tsunakawa, Hidetoshi Shibuya, Masaki Matsushima, Hisayoshi Shimizu, Futoshi Takahashi
    SPACE SCIENCE REVIEWS 154(1-4) 265-303 2010年7月  査読有り筆頭著者
    MAP-PACE (MAgnetic field and Plasma experiment-Plasma energy Angle and Composition Experiment) on SELENE (Kaguya) has completed its similar to 1.5-year observation of low-energy charged particles around the Moon. MAP-PACE consists of 4 sensors: ESA (Electron Spectrum Analyzer)-S1, ESA-S2, IMA (Ion Mass Analyzer), and IEA (Ion Energy Analyzer). ESA-S1 and S2 measured the distribution function of low-energy electrons in the energy range 6 eV-9 keV and 9 eV-16 keV, respectively. IMA and IEA measured the distribution function of low-energy ions in the energy ranges 7 eV/q-28 keV/q and 7 eV/q-29 keV/q. All the sensors performed quite well as expected from the laboratory experiment carried out before launch. Since each sensor has a hemispherical field of view, two electron sensors and two ion sensors installed on the spacecraft panels opposite each other could cover the full 3-dimensional phase space of low-energy electrons and ions. One of the ion sensors IMA is an energy mass spectrometer. IMA measured mass-specific ion energy spectra that have never before been obtained at a 100 km altitude polar orbit around the Moon. The newly observed data show characteristic ion populations around the Moon. Besides the solar wind, MAP-PACE-IMA found four clearly distinguishable ion populations on the day-side of the Moon: (1) Solar wind protons backscattered at the lunar surface, (2) Solar wind protons reflected by magnetic anomalies on the lunar surface, (3) Reflected/backscattered protons picked-up by the solar wind, and (4) Ions originating from the lunar surface/lunar exosphere.
  • Y. Saito, J. A. Sauvaud, M. Hirahara, S. Barabash, D. Delcourt, T. Takashima, K. Asamura
    PLANETARY AND SPACE SCIENCE 58(1-2) 182-200 2010年1月  査読有り
    Mercury is one of the least explored planets in our solar system. Until the recent flyby of Mercury by MESSENGER, no spacecraft had visited Mercury since Mariner 10 made three flybys: two in 1974 and one in 1975. In order to elucidate the detailed plasma structure and dynamics around Mercury, an orbiter BepiColombo MMO (Mercury Magnetospheric Orbiter) is planned to be launched in 2013 as a joint mission between ESA and ISAS/JAXA. Mercury Plasma Particle Experiment (MPPE) was proposed in order to investigate the plasma/particle environment around Mercury. MPPE is a comprehensive instrument package for plasma, high-energy particle and energetic neutral atom measurements. It consists of seven sensors: two Mercury electron analyzers (MEA1 and MEA2). Mercury ion analyzer (MIA), Mercury mass spectrum analyzer (MSA),. high-energy particle instrument for electron (HEP-ele), high-energy particle instrument for ion (HEP-ion), and energetic neutrals analyzer (ENA). Since comprehensive full three-dimensional simultaneous measurements of low to high-energy ions and electrons around Mercury as well as measurements of energetic neutral atoms will not be realized before BepiColombo/MMO's arrival at Mercury, it is expected that many unresolved problems concerning the Mercury magnetosphere will be elucidated by the MPPE observation. (C) 2008 Elsevier Ltd. All rights reserved.
  • Y. Saito, S. Yokota, T. Tanaka, K. Asamura, M. N. Nishino, M. Fujimoto, H. Tsunakawa, H. Shibuya, M. Matsushima, H. Shimizu, F. Takahashi, T. Mukai, T. Terasawa
    GEOPHYSICAL RESEARCH LETTERS 35(24) L24205 2008年12月  査読有り筆頭著者
    Interaction between the solar wind and objects in the solar system varies largely according to the settings, such as the existence of a global intrinsic magnetic field and/or thick atmosphere. The Moon's case is characterized by the absence of both of them. Low energy ion measurements on the lunar orbit is realized more than 30 years after the Apollo period by low energy charged particle analyzers MAP-PACE on board SELENE(KAGUYA). MAP-PACE ion sensors have found that 0.1%similar to 1% of the solar wind protons are reflected back from the Moon instead of being absorbed by the lunar surface. Some of the reflected ions are accelerated above solar wind energy as they are picked-up by the solar wind convection electric field. The proton reflection that we have newly discovered around the Moon should be a universal process that characterizes the environment of an airless body. Citation: Saito, Y., et al. (2008), Solar wind proton reflection at the lunar surface: Low energy ion measurement by MAP-PACE onboard SELENE (KAGUYA), Geophys. Res. Lett., 35, L24205, doi:10.1029/2008GL036077.
  • Yoshifumi Saito, Shoichiro Yokota, Kazushi Asamura, Takaaki Tanaka, Ryota Akiba, Masaki Fujimoto, Hiroshi Hasegawa, Hajime Hayakawa, Masafumi Hirahara, Masahiro Hoshino, Shinobu Machida, Toshifumi Mukai, Tsugunobu Nagai, Tsutomu Nagatsuma, Masato Nakamura, Koh-ichiro Oyama, Eiichi Sagawa, Susumu Sasaki, Kanako Seki, Toshio Terasawa
    EARTH PLANETS AND SPACE 60(4) 375-385 2008年  査読有り筆頭著者
    MAP-PACE (MAgnetic field and Plasma experiment-Plasma energy Angle and Composition Experiment) is one of the scientific instruments onboard the SELENE (SELenological and ENgineering Explorer) satellite. PACE consists of four sensors: ESA (Electron Spectrum Analyzer)-S1, ESA-S2, IMA (Ion Mass Analyzer), and IEA (Ion Energy Analyzer). ESA-S1 and S2 measure the distribution function of low-energy electrons below 15 keV, while IMA and IEA measure the distribution function of low energy ions below 28 keV/q. Each sensor has a hemispherical field of view. Since SELENE is a three-axis stabilized spacecraft, a pair of electron sensors (ESA-S1 and S2) and a pair of ion sensors (IMA and IEA) are necessary for obtaining a three-dimensional distribution function of electrons and ions. The scientific objectives of PACE are (1) to measure the ions sputtered from the lunar surface and the lunar atmosphere, (2) to measure the magnetic anomaly on the lunar surface using two ESAs and a magnetometer onboard SELENE simultaneously as an electron reflectometer, (3) to resolve the Moon-solar wind interaction, (4) to resolve the Moon-Earth's magnetosphere interaction, and (5) to observe the Earth's magnetotail.

MISC

 241

講演・口頭発表等

 202

共同研究・競争的資金等の研究課題

 32

● 指導学生等の数

 4
  • 年度
    2021年度(FY2021)
    博士課程学生数
    1
    修士課程学生数
    2
  • 年度
    2020年度(FY2020)
    博士課程学生数
    1
    修士課程学生数
    2
  • 年度
    2019年度(FY2019)
    博士課程学生数
    2
    修士課程学生数
    2
  • 年度
    2018年度(FY2018)
    博士課程学生数
    2
    修士課程学生数
    3

● 専任大学名

 1
  • 専任大学名
    東京大学(University of Tokyo)