Development of a Cryogenic High Voltage Multiplier

A classic electrostatic induction machine, Cavallo's multiplier, can be used for in situ production of very high voltage in cryogenic environments, starting with a much more modest high voltage fed in from outside the cryostat. The device is suitable for generating a large electrostatic field under conditions of very small load current. This talk will describe efforts to develop this device for a cryogenic neutron electric dipole moment experiment, in which a measurement cell filled with and surrounded by sub-1 Kelvin liquid helium is expected to withstand a working voltage of 650 kV across ≈8 cm. This talk will describe a cryogenic test apparatus, currently under construction at Los Alamos National Laboratory, to develop a Cavallo apparatus for the nEDM experiment and to test the effect of nearby sparks on SQUID magnetometers.