Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||National Astrpopmical Observatory|
YAMASHITA Yasumasa Optical Infrared Astronomy Division, National Astronomical Observatory, 光学赤外線天文学研究系, 教授 (50011458)
TANABE Toshihiko Faculty of Science, University of Tokyo, 理学部, 助手 (90179812)
ISOBE Syuzo Optical Infrared Astronomy Division, National Astronomical Observatory, 光学赤外線天文学研究系, 助教授 (20012867)
NISHINO Yohei Solar Physics Division National Astoronomical Observatory, 太陽物理学研究系, 助手 (40189296)
KITAI Reizaburo Faculty of Science, Kyoto University, 理学部, 助手 (40169850)
SUEMATSU Yoshinori Solar Physics Division National Astronomical Observatory, 太陽物理学研究系, 助手 (50171111)
KUROKAWA Hiroki Faculty of Science, Kyoto University, 理学部, 助教授 (80135508)
HIRAYAMA Tadashi Solar Physics Division National Astronomical Observatory, 太陽物理学研究系, 教授 (20012841)
中村 士 国立天文台, 光学赤外線天文学研究系, 助手 (80107474)
代情 靖 国立天文台, 太陽物理学研究系, 助手 (60158516)
船越 康宏 京都大学, 理学部, 教務職員 (80127133)
|Project Period (FY)
1990 – 1991
Completed(Fiscal Year 1991)
|Budget Amount *help
¥8,000,000 (Direct Cost : ¥8,000,000)
Fiscal Year 1991 : ¥6,000,000 (Direct Cost : ¥6,000,000)
Fiscal Year 1990 : ¥2,000,000 (Direct Cost : ¥2,000,000)
|Keywords||Total Solar Eclipse / 11 JUly, 1991 / Solar Corona / Japanese Eclipse Expedition / Mexico / LA PAZ City / Universidad Autonoma DE Baja California Sur / MT. Popocatepetle / 予備調査 / 南バハカリフォルニア自治大学|
The 11-July-1991 Eclipse was one of the most important eclipse in this century because of its longest duration of totality. The purpose of this research project was to observe the solar corona and to study its physical condition by using this rare oppoetunity.
Japanese Eclipse Expedition consists of three institutes, i. e. National Astronomical Observatory (6persons), Kyoto university (3persons), and Hydrographic Department of Japan (2persons). The former two institutes were supported by this Grant under The Monbusho International Scientific Research. Three teams from Nationl Astron. Obs., Kyoto Univ. and Hydro. Depart. observed at the Campus of UABCS (Universidad Autonoma de Baja California Sur), and one team from National Astr. Obs., on the top of Mt. Popocateptle. The sky condition was perfect and the seeing condition was good at UABCS. It was fine before the 2nd contact, but a thin cirrus ran over the sun at Mt. Popocatepetle.
The instrumentation, general features of obtained data, a
nd the results of a preliminary analysis are briefly summarized below.
(1) Observation of Fine Structures in the Inner Corona
High resolution pictures of the inner corona were obtained in the lights of FeX6374A, FeXIV5303A, CaXV5694A, Halpha lines and 6100A continuum. The 6374 loop structures are found to be finer than any other 10^6K coronal loops which have ever been published. The emission-line images represent the fine structures of 1x10^6K (FeX), 2x10^6K (FeXIV), 3.5xl0^6K (CAXV) and 1x10^4 (HI) respectively, and the continuum images show the electron column density distribution. The detailed cottiparison of thein enables us to study the temperature-density structures of various types of coronal fine structures.
(2) Observation of the Cool Material in the Corona
The coronal images were taken in the light of HeI10830A, Fe5303A linese and 10000 continuum. Spectrographic observations were also made in the wavelength region of violet (lambda lambda3760-4060) and infrared (lambda lambda10745-10835)to obtain the detailed physical condition of the corona, especially of its cool part. The data obtained does not show any distinct cool structures other than ordinary prominences.
(3) Observation of the Coronal Rays
White light coronal pictures were observed to study the width-variations of the coronal rays. It is found that most of the rays expand lineally with distance with the rate of 20-50 arcsec per solar radius.
(4) Polarization Observation of the Solar F-Corona
Polarization of F-corona was measured in four wavelengths, i. e., 5325A, 5965A, 7200A, 8015A to study how far interplanetary dust grains reach to sun. With some assumptions, the map of two dimensional polarization distribution of the outer corona was obtained. It shows high polarization regions co-incident with coronal streamers. Less