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While Dr. Wilson's contributions to accelerator technology are well known, I would like to make this audience aware of his considerable contributions to accelerator radiation protection. In 1952, Dr. Wilson performed one of the first Monte-Carlo calculations of the propagation of the electromagnetic cascade. Done before the widespread availability of computers, wheels of chance were used to simulate events. The published results stand to this day as being surprisingly accurate. Though performed for physics research purposes, they set the scale needed to understand radiation safety issues in a rudimentary manner.
Later, when he was creating Fermilab from the green sod of the Illinois prairie, Wilson took an innovative approach toward the development its radiation safety program. He was a creative genius with the artistic talent of an accomplished sculptor who threw himself full force against the "conventional wisdom" of how to run a laboratory. Wilson understood the importance of radiation safety, but rather than to rely on "professionals" specifically educated in the field of health physics, he chose instead to recruit individuals holding Ph.D.'s in nuclear and particle physics who had an interest in, and aptitude for, radiation protection.
Wilson, apparently, believed that such individuals "had what it took" to solve the radiation problems of a large accelerator because they would have a higher level of knowledge of the physical processes involved compared with that of "typical" radiation protection specialists. This philosophy of staffing the leadership level of Fermilab's radiation protection program has continued to the present day. An important benefit of this tradition is that it allows for the leaders of the radiation protection effort to maintain their participation in basic scientific research through their participation in Fermilab experiments. This cross-fertilization has been extremely useful. In fact, several of the physicists initially recruited by Wilson later excelled in other areas not directly associated with radiation protection. As a reflection of the spirit of this program, the radiation protection program at Fermilab was deliberately called "radiation physics" rather than "radiation control" or "health physics", nomenclature that has persisted, at least informally, to the present day. Wilson's most crucial recruit for the task of establishing the radiation physics program, which set the tone for its success, was his first, the late Dr. Miguel Awschalom.
Wilson, due to both his artistic talents and his love of the outdoors, desired to build a laboratory that was both aesthetically pleasing and environmentally protective. Thus, environmental protection was important at an early stage in the building of Fermilab. Wilson was very much aware of the fact that the laboratory was located near a densely populated metropolitan area. He realized that the farmland in the vicinity of Fermilab during the late 1960s was likely to become the suburban residential area that it now is. These considerations, and perhaps others, led Wilson to issue a statement in June of 1971 that it would be the goal of Fermilab not to exceed a dose equivalent of 10 millirem per year at any point on the site boundary.
This limit, stated at a time when the comparable Atomic Energy Commission limit was 500 millirem per year to a given member of the general public, was considered by many to be "astoundingly" low. As it has turned out, this goal has never been exceeded by more than 4 millirem throughout the history of Fermilab. The application of this goal has served Fermilab well in keeping radiation exposures to the general public to very low levels compared to natural background sources. Similar stringent standards were developed and applied to the control of radioactivity produced in soil to protect groundwater supplies.
As some of my colleagues know, a number of the radiation safety instruments that have been designed "in house" at Fermilab are known by unusual names such as "albatross", "chipmunk", "scarecrow", and "wallflower". The name of the one of these instruments, a neutron monitor based on a moderating "pseudosphere", was clearly chosen as a result of Dr. Wilson's interest in the radiation protection program. When this particular instrument was designed, Awschalom and his colleagues envisioned a system employing a number of such detectors connected to a central rate meter. Apparently, Wilson, in general, disliked the idea of central controls. When Awschalom presented this idea to Wilson, it is reported that Awschalom was told in no uncertain terms that the units must have local radiation level readouts and be self-contained. Wilson's directive complicated the design considerably, and Awschalom and his group felt that Wilson's preferences had been "imposed" upon them. The detector was thus named, appropriately, the "albatross". However, in actual use in real radiation fields, the advantages of decentralized electronics quickly became evident. The naming of the albatross also established the tradition of giving Fermilab radiation instruments "unusual" names.
I arrived at Fermilab in mid-1978, just about the time that Wilson stepped down as Director. Thus my recollections have been garnered from others who had worked directly with him and from the Fermilab historical archives. However, it was my privilege to meet this great man and converse with him on a small number of occasions.