Magnetic field shield for high resolution nondestructive DC current monitors

用于高分辨率无损直流电流监视器的磁场屏蔽

• 批准号: 09640357
• 负责人: HATANAKA Kichiji
• 金额: $ 1.86万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09640357/
• 关键词: DC current monitor; Superconducting; SQUID; Magnetic field shield; 超電等; 超電受量子干渉素子; 電磁モニター; 超電導量子干渉素子

A beam intensity monitor using a SQUID was designed at RCNP in order to measure the ion beam intensity in a non-destructive manner.1. Magnetic field shilding is an essential point to realize the high resolution. Shielding effects of superconductors were simulated following the London equation.2. Two types of small-sized models were tested ; a coaxial cavity and a folder type cavity with five ring type shield elements. Cavity walls were made of 1 mm thick lead.3. A double washer DC SQUID was used as the magnetic flux sensor.4. For the coaxial type cavity, the shielding efficiency of 10ィイD1-13ィエD1 was observed as expected from the numerical simulations. However, the caxial cavity cannot be used as an actual monitor, because it is generally difficult to accommodate the long cavity in the beam line.5. Shielding efficiency of the folder type cavity was measured to be 10ィイD1-8ィエD1 which was 10 times worse than numerical estimations.6. From these investigation, a current monitor was designed and fablicated. From preliminary tests, 10 nA current was detected with 1-2 nA resolution.

为了以非破坏性的方式测量离子束强度，RCNP设计了一种使用SQUID的束强度监测器.磁场屏蔽是实现高分辨力的关键。采用伦敦方程模拟了超导体的屏蔽效应.两种类型的小尺寸模型进行了测试;同轴腔和折叠式腔与五个环型屏蔽元件。空腔壁由1 mm厚的铅制成。采用双垫圈直流SQUID作为磁通传感器.对于同轴型腔，如数值模拟所预期的那样，观察到10 μ m D1-13 μ m D1的屏蔽效率。但是，同轴腔不能用作实际的监视器，因为它通常很难容纳光束线中的长腔。折叠式腔体的屏蔽效率被测量为10毫米D1-8毫米D1，比数值估计差10倍。在此基础上，设计并制作了电流监测仪。根据初步测试，以1-2 nA分辨率检测到10 nA电流。

项目成果

Y.Sasaki,K.Hatanaka,et al.: "Nondestructive DC Beam Current Monitor with Nano-Ampere Resolution"Proc.of The XVI RCNP Osaka Int.Conference. 249-251 (1997)

Y.Sasaki,K.Hatanaka,et al.：“具有纳安分辨率的无损直流束电流监测器”第 XVI RCNP 大阪国际会议记录。

Y.Sasaki,K.Hatanaka,et al.: "Nondestructive DC Beam Current Monitor with Nano-Ampere Resolution"Proc.of The 11th Symposium on Accelerator Science and Technology. 255-257 (1998)

Y.Sasaki，K.Hatanaka，等：“具有纳安分辨率的无损直流束流监测器”第十一届加速器科学与技术研讨会论文集。

Y. Sasaki K. Hatanaka et al.: "Nondestructive DC Beam Current Monitor with Nano-Ampere Resolution"Proc. Of The First Asian Particle Accelerator Conference. 543-545 (1999)

Y. Sasaki K. Hatanaka 等人：“具有纳安分辨率的无损直流束电流监测器”Proc。

Y.Sasaki: "Nondestructive DC Bean Current Monitor with Nano-Ampere Resolution" Proc.of the 11th Symposium on Accelerator Science and Technology. 255-257 (1997)

Y.Sasaki：“具有纳安分辨率的无损直流豆电流监测器”第十一届加速器科学与技术研讨会论文集。