Grant-in-Aid for Overseas Scientific Survey.
|Research Institution||Faculty of Science, Shinshu University|
MORI Satoru Faculty of Science, Shinshu University, Japan, 理学部, 教授 (50020649)
森下 伊三男 朝日大学, 経営学部, 助教授 (40148200)
DULDIG M.L. オーストラリア, 南極局, 主任研究員
FENTON K.B. タスマニア大学, 名誉教授
FENTON A.G. タスマニア大学, 名誉教授
HUMBLE J.E. タスマニア大学, 物理, 准教授
藤井 善次郎 名古屋大学, 太陽地球環境研究所, 助手 (10022724)
宗像 一起 信州大学, 理学部, 助手 (40221618)
安江 新一 信州大学, 理学部, 講師 (80020668)
M.L.DULDIG オーストラリア, 南極局, 主任研究員
K.B. Fenton タスマニア大学, 名誉教授
A.G. Fenton タスマニア大学, 名誉教授
J.E. Humble タスマニア大学, 物理学科, 助教授
DULDIG Marcus L. Australian Antarctic Division, Australia
FENTON Keith B. University of Tasmania, Australia
FENTON Arthur G. University of Tasmania, Australia
FUJII Zenjro Solar-Terrestrial Environment Laboratory, Nagoya University, Japan
HUMBLE John E. Department of Physics, University of Tasmania, Australia
YASUE Shinichi Faculty of Science, Shinshu University, Japan
MUNAKATA Kazuoki Faculty of Science, Shinshu University, Japan
|Project Fiscal Year
1991 – 1992
Completed(Fiscal Year 1992)
|Budget Amount *help
¥4,700,000 (Direct Cost : ¥4,700,000)
Fiscal Year 1992 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Fiscal Year 1991 : ¥3,500,000 (Direct Cost : ¥3,500,000)
|Keywords||high energy cosmic rays / sidereal ansiotropy / north-south asymmetry of sidereal ansiotropy / underground observation of cosmic rays / two hemisphere observation of cosmic rays / 高エネルギー宇宙線 / 恒星時異方性 / 異方性の南北非対称性 / 宇宙線の地下観測 / 宇宙線の両半球観測 / 宇宙線 / 太陽磁気圏 / 南北非対称異方性 / 連続観測 / 宇宙線大気効果|
In order to study the north-south asymmetry in the intensity variation, particulary of sidereal anisotropy, of high energy cosmic rays (-10^<12>eV) we have collaboration between Shinshu University, Nagoya University and University of Tasmania for the period 1991-1992. We have started two hemisphere observations at two stations ; one at Matsushiro in the northen hemisphere and the other at Liapootah, Australia since December 1991. Two stations are located at a conjugate position at a similar geographical latituide and longitude, at almost the same depth underground of 220m.w.e. at Matsshiro and 154m.w.e. at Liapootah, respectively. The identical muon telescopes are installed ; 25m^2 in area at Matsushiro, and 20m^2 in area at Liapootah, both of which of multi-directional type. The telescopes and the electronics systems at both stations have been connected with each laboratory for controlling and data sending, by means of personal-computer systems, via pulic telephone lines.
servations commenced in December 1991 at Liapootah (at Matsushiro the observation has been carried out since April 1984).
The following preliminary results are obtained :
1. Observed counting-rates are in good agreement with those expected for each directional telescope at Liapootah.
2. The measured counts well follow the Poisson fluctuation as expected.
3. Good correlations (With coefficient -0.4 for 2968 data points) have been found between the observed intensity variations for the vertical telescope and the variations of the barometric pressures measured at Hobart (-90 km in distance). The barometer coefficient is -0.03%/hp, which is in agreement with th theoretical values by taking into accounts the upper atmospheric temperature effect.
4. Mothly average values show a remarkable semi-annual variation as likely to that at Matsushiro ; two maxima at summer and winter seasons. These also can be well explained in terms of the temperature effect.
5. The intensity variations are harmonically analyzed in solar, sidereal and anti-sidereal time, respectively. Significant sidereal diurnal vector is obtained at Liapootah for the vertical telescope as ; 0.057*0.014%, 3.1*1.0hr SLT. The value may be compared with that at Matsushiro ; 0.030*0.027%, 2.5 hr LST. This indicates that significant north-south asymmetry may be found in sidereal variation as has been expected.
6. Monthly diurnal vectors in each time coordinate has been examined. It is well established that month-to-month movement of sidereal vectors, for example, can be well explained in terms of annual movements of solar and anti-sidereal vectors and their synthesis.