“SHOOTING” AT ATOMS

Wanganui Chronicle, Volume 79, Issue 196, 22 August 1935, Page 10

“SHOOTING” AT ATOMS

Super-Giant Tube Described

One year's research in the building of a super-giant vacuum tube able to withstand terrific pressure set up in Technology’s 10,000,000-volt electrostatic generator, was described by Dr Karl T. Compton, president of Massachusetts Institute of Technology, before directors of the Research Corporation. Knowing that ordinary vacuum tubes would be blown to bits by the first flash-over from the poles ol Tech’s *‘atom gun/’ engineers under the direction of Dr. Robert J. Van de Graaff have designed and nearly completed a great cylinder of papier macho, as strong as steel and capable of swallowing several dozen ordinarysized X-ray tubes. Outlined by Dr Compton, tho building of such a hollow tube, one foot in diameter, 1-1 feet long, has been a scientific problem as difficult us the original design of the generator. Meanwhile, it was revealed that the generator itself has undergone improvement. Accurate voltage and current controls, as well as vibration elimin ators, have been installed. With th< completion of preliminary tests early in June, experiments in atomic d’sinte gration were expected to begin. The tube, when finished, will consist of five identical units, penned ent] to end and sealed to metal cans at the

two extremities. Through one end will bo loosed the beam of proton particles, invisible millets; through the other will appear atomic targets. The hollow tube is designed for rapid pumping out of air, Dr. Campton told tho directors, and it is provided internally with a series of specially built metal shields to hold the beam of electrified particles accurately in focus and distribute voltage along tho *ube in the most advantageous manner. Ln operation, the protons ire fed into the magazine end of die tube like cartridges on a machine gun belt. The kick is administered by the electrical output of tho generator, so that a steady stream of particles is directed on atom targets made of thin sheets of various metals at the muzzle cud. An important development resulting from investigations already carried out with the generator, was the discovery that very penetratin'- X-rays up to 700,000 volts could gained z coupling the Van de Graaff belt generator with a modified Lauritsen X-ray tube The advantages if such a hook-up over previous X-ray outfits, Dr Compton asserts to be demonstrated in cheapness, simplicity of construction, case and accuracy of voltage and current control; and most important of all, the entire current at maximum voltage is used to produce A-rnvs.