Approach to understand the solar coronal and chromospheric heating --- from Hinode, IRIS & CLASP to SOLAR-C

2018 Fiscal Year Final Research Report

• Project/Area Number: 25220703
• Research Category: Grant-in-Aid for Scientific Research (S)
• Allocation Type: Single-year Grants
• Research Field: Astronomy
• Research Institution: National Astronomical Observatory of Japan (2017-2018); Japan Aerospace EXploration Agency (2013-2016)
• Principal Investigator: Tsuneta Saku 国立天文台, 大学共同利用機関等の部局等, 台長 (50188603)
• Co-Investigator(Kenkyū-buntansha): 勝川 行雄 国立天文台, 太陽観測科学プロジェクト, 准教授 (00399289)
• Research Collaborator: KANO Ryouhei ; KUBO Masahito ; ISHIKAWA Ryohko ; BANDO Takamasa ; NARUKAGE Noriyuki ; OKAMOTO Takenori ; GOTO Motoshi ; HARA Hirohisa ; SAKAO Taro ; ISHIKAWA Shinnosuke ; SUEMATSU Yoshinori ; IMADA Shinsuke ; KATO Yoshiaki ; IIDA Yusuke ; GIONO Gabriel ; YOSHIDA Masaki ; SONG Donguk ; TRUJILLO BUENO Javier ; KOBIKI Toshihiko ; DE PONTIEU Bart ; ANTOLIN Patrick ; LEE Kyoung-Sun ; TEI Akiko ; KONO Shunya ; CARLSSON Mats ; LEENAARTS Jorrit ; PEREIRA Tiago
• Project Period (FY): 2013-05-31 – 2018-03-31
• Keywords: 太陽活動 / 太陽フレア / 彩層 / コロナ / 磁場 / 量子原子偏光 / 量子ハンレ効果 / ゼーマン効果

Outline of Final Research Achievements

The innovative precision UV polarimeters CLASP1 and CLASP2 developed in this research and launched onboard two NASA sounding rockets discovered quantum atomic polarization and the quantum Hanle effect in the solar transition region and chromosphere for the first time. These confirmed quantum-mechanical phenomena provide us with new means to measure magnetic fields in the solar corona, transition region, and chromosphere. These magnetic fields have been very difficult to measure with the classical Zeeman effect alone. These new observation methods will facilitate new research, such as obtaining critical information about the propagation and dissipation of magnetohydrodynamic waves throughout the chromosphere/transition region all the way to the corona. These methods will also enable the identification of magnetic neutral points/lines, from which solar flares emanate, to better understand and predict solar activity which affects modern civilization and humanity.

Free Research Field

数物系科学、太陽物理学

Academic Significance and Societal Importance of the Research Achievements

独創性の高い高精度紫外線偏光分光観測装置により、量子原子偏光と量子ハンレ効果の世界初確認に成功し、ゼーマン効果では困難なコロナ・遷移層・彩層の磁場観測を科学衛星で行う科学技術基盤を築いた。これにより、コロナ加熱や太陽フレアの発生や予報など、未解決課題の解明の端緒を開いた。太陽活動の高度文明に与える潜在的脅威の観点からも、社会的意義は高い。本研究の成果は、日本の次期太陽観測衛星のみならずNASAやESAの将来計画の企画立案に、科学と技術の両面で大きく貢献するであろう。