抄録
This paper presents a new concept for a cylindrical magnetic shield with magnetic shaking enhancement. The shield consists of two C-shaped blocks. Magnetic shaking enhancement was properly applied to the block as a result of a closed magnetic flux pass. The shape of the shield is a double concentric shell with two magnetic shunts between the outer and inner shells. The effect of the shunts on shielding performance was analyzed using an FEM program. A prototype shield model, (length: 20cm, diameter: 7.5cm, shell thickness: 0.04mm), was made by winding a cobalt-based amorphous ribbon, Metglas2705M, twice around a paper tube cut in half transversally. A large and constant transverse shielding factor of 1, 000 was obtained even against a weak low-frequency magnetic field as low as 0.1Hz, 10nT.
