MAGNETIC-SUSCEPTIBILITY OF MATERIALS SCREENED FOR USE IN FABRICATING A NONMAGNETIC LIQUID-HELIUM DEWAR

In order to obtain a low noise environment for optimum performance of SQUID sensors, it is essential to minimize the magnetic signal of the materials used in the SQUID cold electronics and the structures surrou nding these sensors. We have, therefore, screened samples for potentia l use in the fabrication of a low-noise dewar that would house a low-T -c SQUID device. Susceptibility measurements were made at room tempera ture and 4.5 K in order to determine if the materials would be good ca ndidates for use in the construction of the dewar. The results of thes e magnetic susceptibility measurements are reported together with the materials' use and supplier.