Page 80 - Neutrons for Sciences and Society

Neutrons for Science
4.1 The Neutron Source
Dautray and Beckurts immediately set to work on the reactor project. Both had existing groups to help. Kouts who had built the HFBR at Brookhaven spent much of 1966 at Saclay bringing all his experience with no reservations. The Soviet knowledge was also very valuable. In June 1966 a group led by Pierre Balligand (Néel’s assistant at the CENG) and comprising nearly all the French who participated on the design team, visited the USSR to see what was being done on research reactors, and to discuss the fuel element.
The idea of a pulsed reactor was quickly abandoned for the reasons I have already mentioned above. However Maier-Leibnitz always regretted dropping the Ispra group which continued their own activities towards a pulsed reactor project. In Dautray’s notes and his questions where I have written records there is never any questioning of a static source. There remained many other choices to be made. The year 1966 was filled with meetings to make decisions on various aspects of the design.
4.1.1 Choice between light and heavy water
The most important decision concerned the choice of using ordinary water or heavy water as coolant for the reactor core. The source presented at Geneva used ordinary water. This was the logical consequence of choosing a swimming pool option. Heavy water offers some distinct advantages. These result mainly from
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