E989

Features:

 Made of high-permeability permalloy (Ni: 78 %, Fe and others: 22 %)
Various sizes available with inner diameters from 12 mm to 138 mm
Lusterless black paint finish


Description

Photomultiplier tubes are extremely sensitive to magnetic fields and exhibit  output variations even from sources such as terrestrial magnetism.

Hamamatsu E989 series magnetic shield cases are designed specifically to protect photomultiplier tubes from the influence of such magnetic fields.  The E989 series uses permalloy, a material that has an extremely high per-meability (approximately 105). The magnetic field intensity within the shield case can be attenuated from 1/1000 to 1/10000 of that outside the shield  case (this ratio is called the shielding factor). The E989 series ensures a stable output for photomultiplier tubes operating in proximity to magnetic fields.