Design study of the heliospheric imager

日光层成像仪的设计研究

• 批准号: 10554022
• 负责人: TOKUMARU Munetoshi
• 金额: $ 3.78万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10554022/
• 关键词: solar wind; CME; interplanetery scintillation; tomography; radio observation; アレーアンテナ; プラズマ; トモグラフィー法

Research of a new instrument for imaging heliosphere (heliospheric imager) and related studies have been done.(1) Heliospheric ImagerIn the first year, we designed the heliospheric imager. Very large effective area at least 3000mィイD12ィエD1 and reducing urban noise about 30dB are required to observe weak radio sources. For these reasons. a phase array antenna surrounded by metallic-fence with 10m height was adopted for the heliospheric imager. Thus we designed a phased array which consists of 16384 λ/2-dipole elements (256E-W) x 64(N-S), 3500mィイD12ィエD1). The sensitivity of the antenna is expected to be 0.2 Jy which will be the highest one among those of the current IPS network in our laboratory.Various parts such as a dipole element, a schpertop balun and connectors are developed and tested electric performance. Especially these are designed for mass production to cut down the cost. We success to develop a low ohmic-loss (-0.02dB) connector which can be used in the heliospheric imager. And also suitable cable (MFH-8AC) was found which have enough strength and low velocity factor.In the second year, we built a small phased array antenna (16(E-W) x 8(N-S), 32mィイD12ィエD1 to check our design. The antenna impedance is measured to be about 170Ω which well agrees with design calculation. The Sun and QSOs (3C273, 3C405) were observed to measure beam size, system temperature and aperture area, and they are 6.5 degree (FWHP), 290 K and 17mィイD12ィエD1 respectively. These values also agree with calculated ones. In conclusion, the design can be applied to the heliospheric imager.(2) Related StudiesOrigin compact very low speed solar wind and propagation of interplanetary disturbances measured with IPS were studied in these two years. These analysis techniques will be applied to new observations with the heliospheric imager. We expect that the new data will provide us further insights of dynamical phenomena in heliosphere.

第一年的新仪器（Heliosperic Imaster）的成像（Heliospherimager成像）设计了高效的面积，至少有3000m II D12用于Heliosepheric成像器的原因。 Schpertop Balun和连接器诸如偶极子元素，以降低成本合适的电缆（MFH-8AC）t一个小的相阵列天线（16（e-w）x 8（n-s），32m B. B. d12 tock我们的设计。对天线的测量为170Ω，使用设计计算。SUND和3C405）观察到梁的大小，系统温度和孔径区域，分别是6.5度（FWHP），290 K和17m II D1。在这两年中，这些分析技术与Heliospheric Imager一起应用于新的BSERTENS。

项目成果

Ananthakrishnan, S.: "Origin of travelling interplanetary disturbances" Advances in Space Research. (in press).

Ananthakrishnan, S.：“行星际扰动的起源”空间研究进展。

Kojima, M.: "The highest solar wind velocity in a polar region estimated from IPS tomography analysis" Proceedings of SOHO 7 Workshop. (in press).

Kojima, M.：“根据 IPS 断层扫描分析估算极地最高太阳风速度”SOHO 7 研讨会论文集。

Yokobe, A. et al.: "Radial distance dependence of the solar wind speed at high latitudes observed by interplanetary scintillation"Advanced Space Research. 25. 1947-1950 (2000)

Yokobe, A. 等人：“通过行星际闪烁观察到的高纬度太阳风速的径向距离依赖性”高级空间研究。

Kojima M. et al.: "The highest solar wind velocity in a polar region estimated from IPS tomography analysis"Space Science Review. 87. 237-239 (1999)

Kojima M. 等人：“根据 IPS 断层扫描分析估算极地最高太阳风速度”《空间科学评论》。

Tokumaru, M.: "Large-scale structure of solar wind turbulence near solar activity minimum" Advances in Space Research. (in press).

Tokumaru, M.：“太阳活动最小值附近太阳风湍流的大规模结构”空间研究进展。