Electrostatic Dipoles

One electostatic dipole consists of two curved plates, a negatively charged cathode and positively charged anode. The electrodes have the shape of coaxial cylinders differing by 10 cm in radius, average radius 200 cm and extending through an arc of 20 degrees. The voltage difference between cathode and anode may be as much as 400,000 volts DC.

The high voltages are produced by Cockroft-Walton generators: through a ladder network of diodes and capacitors, a voltage of several kilovolts alternating at radio-frequency is multiplied up to a large DC voltage. To inhibit voltage breakdown between electrodes or between electrodes and ground, sharp corners had to be avoided and the facing surfaces of the titanium electrodes were hand-polished to a mirror finish. The electrodes are supported on insulators which can withstand the high voltages, while keeping the 10-cm gap constant to within 0.01 cm. The second electrostatic dipole is even larger: it is curved on a 2.5 m radius and extends over an arc of 35 degrees.