Saskatchewan Accelerator Laboratory

Around 1947 members of the Department of Physics at the University of Saskatchewan decided to obtain a 25 MeV Betatron. The principal interest was in nuclear physics, but they were also interested In the possible therapeutic uses for the treatment of cancer, Funding was obtained from the Atomic Energy Control Board , the National Research Council (NRC), the National Cancer Institute, local cancer societies and the university. The machine was installed in summer 1948 in a new building built in one angle of the existing Physics department, connected to the main building. It was manufactured by the Allis-Chalmers Company of Milwaukee, Wisconsin, and was very similar to the one being used at the time by Donald Kerst at the University of Illinois.{{Cite journal |last1=Harrington |first1=E. L. |last2=Haslam |first2=R. N. H. |last3=Johns |first3=H. E. |last4=Katz |first4=L. |year=1949 |title=The Betatron Building and Installation at the University of Saskatchewan |journal=Science |volume=110 |issue=2855 |pages=283–285 |doi=10.1126/science.110.2855.283 The first cancer patient was treated on Mar. 29, 1949 starting the really first concerted clinical investigation of the usefulness of the betatron as a radiotherapeutic tool, with over 300 patients treated in 17 years of operation. The success of the program led to the installation of the world's first cobalt-60 source for radiotherapy at the university in 1951. ==Linear Accelerator: 1962–1983==

The construction of the Linear Accelerator (LINAC) was announced in September 1961, Construction officially began on May 10, 1962, when Sir John Cockcroft, Nobel Prize in Physics winner, ceremonially turned the first sod. The accelerator was designed and constructed by Varian Associates. It was a four-section 140 MeV machine operating, with the first section designed for higher current (and thus lower energy) for radiation chemistry. A 270" magnetic system at the end of the first section could divert the electron beam for such research. For radiation protection purposes the accelerator and research facilities were housed in an underground building with 10 feet of compacted gravel above it and considerably thicker shielding over the regions where the full beam intensity was diverted into the experimental areas. During the 1970s SAL regularly published important nuclear physics results, and the LINAC was upgraded to 220 MeV in 1975, and 300 MeV in 1980. ==EROS: 1984–1996==

Linear accelerators have an inherently low duty cycle, and one solution to this is to add a storage ring - a so-called pulse-stretcher ring (PSR). The short particle bursts from the LINAC are injected into the storage ring, and in the time between two bursts the circulating electrons are slowly extracted from it, to give a nearly continuous beam. A PSR had been proposed for SAL as far back as 1971, and much of the pioneering work on PSRs had been performed by SAL scientists. In 1983 funding was obtained for a PSR for SAL, As an economical solution, the ring was squeezed into the existing building by the "ingenious expedient" of hanging it from the ceiling. An energy compression system was also installed in the late 1980s, and by 1990, with EROS operational, SAL was once more at the forefront of medium energy nuclear physics. In 1991 the underground experimental area EA2 was enlarged to house a new electron scattering spectrometer. By 1994 SAL was operating 24/7, delivering about 5000 hours of beam for experiments per year. In 1994 an NSERC panel had proposed that a synchrotron should be built in Canada, and SAL director Dennis Skopik convinced the university to bid to host the new facility. ==The Canadian Light Source and the end of SAL==

The two Universities bidding to host the new synchrotron facility - the Canadian Light Source (CLS) were Saskatchewan and the University of Western Ontario (UWO). NSERC set up a committee of international experts to recommend one of the two sites. Funding still had to be found for the new facility, and it was not until 1999, that the full funding needed was awarded. The end-point tagger was transferred to MAX-Lab at Lund University. In 2002 the SAL LINAC was refurbished to operate at 250 MeV and now serves as part of the injection system for the CLS storage ring. The current CLS building, finished in 2001, incorporates the old SAL building, with much larger addition built directly adjoining it to house the synchrotron storage ring. The former SAL underground experimental area EA2 now houses a 35MeV LINAC which is part of a CLS project to produce the medical isotope technetium-99m, a mainstay of nuclear medicine. ==External links==