A one tenth scaled magnetically shielded room of double cylindrical HTS combined with ferromagnetic metals

摘要

This paper deals with a cylinder with both ends closed and a hole at the middle point on the side of both cylinders. The holes can be aligned to permit the examinee to enter or exit the double cylindrical MSR (Magnetically Shielded Room). An MSR one tenth the size of a human body was made. The diameter and length of the cylinder were 250 mm and 350 mm, respectively. The size of the hole was 90 mm/spl times/180 mm. The material used for this MSR was mainly high T/sub c/ superconductor with a coating of Bi/sub 2/Sr/sub 2/Ca/sub 1/Cu/sub 2/O/sub x/ 100 /spl mu/m thick. The ends of the MSR were plated with permalloy. To detect the inner magnetic fields at various points of the MSR, 33 sensors with three-dimensional sensitivity were placed at one closed end. The ratio of the internal to external field strength was measured by applying external magnetic fields parallel and perpendicular to the door. The readings of the ratios obtained were 10/sup -2/ to 10/sup -3/ in the parallel and 10/sup -3/ to 10/sup -4/ in the perpendicular case.