An Automated Ac Susceptibility Set up Fabricated Using a Closed-Cycle   Helium Refrigerator
  We have described here the design and operation of an automated ac susceptibility set up using a closed cycle helium refrigerator. This set up is useful for measuring linear and nonlinear magnetic susceptibilities of various magnetic materials. The working temperature range is 2 K to 300 K. The overall sensitivity of the set up is found to be 10-3 emu. 
S. Kundu and T. K. Nath
physics.ins-det