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Harvard's facilities for nuclear research date back quite a while. Before the Second World War, the University owned a small, constant frequency cyclotron ("the only kind available at that time," says William M. Preston, director of the current cyclotron laboratory). During wartime, however, this machine was appropriated by the government and taken out to Los Alamos for use in the experiments that led to the atomic bomb...
...present, Preston says, the Harvard machine can be considered an "intermediate energy cyclotron;" there are about half a dozen larger accelerators of this type in the world. Beyond a certain level of energy (about 600 million electron volts), he says, this particular type of machine (utilizing a single large magnet) is no longer practicable, because of the large size of the magnet required. Therefore, new methods involving a series of magnets, such as those used in the Cambridge Electron Accelerator and the Brookhaven cyclotron, had to be devised...
...chief difference between the cyclotron and the Electron Accelerator, according to Preston, aside from the obvious fact that the former works with protons and the latter with electrons, is one of method. In the cyclotron the protons are subjected to a constant magnetic field and spiral out in ever-increasing orbits; in the election accelerator, on the other hand, the orbit is constant and the magnetic field is increased in order to keep the electrons in a stable path. The cyclotron, Preston says, unlike the C.E.A., can properly be called an "accelerator," for the velocity...
...beam is directed into an experimental area. There are, however, no serious problems here of deflecting the particles: once the spiraling beam reaches the outer limit of the cyclotron chamber, it can be made to fly off on a tangential line into the experimental area. A typical experiment, Preston says, might involve a beam hitting a target of some element, perhaps carbon. Counters would be set up at various angles to the beam at the point of collision, and the data thus obtained--used with the laws of momentum--might give important information as to the nature of the carbon...
Tucker cannot quite match the brash enthusiasm of Robert Preston...