| 摘要 |
A magnet assembly has a generally U-shape, the bight (3) of the U including a permanent magnet (4) which generates a magnetic field whose flux passes through a working volume defined between the arms (1, 2) of the U. The dimensions of the assembly are chosen such that Lg/Lm=Br/2Bg(1) where Lg is the length of the gap between the arms, Lm is the length of the magnet, Br is the remnant field of the magnet, and Bg is the field in the gap. |
