Report on NATO Science Committee Dr. Norman Ramsey reported on the status of activities and problems of the NATO Science Committee and on his position as Science Adviser to NATO. There were no actions taken by the PSAC. Dr. Ramsey outlined the following areas of help he might expect from the PSAC: a. Support of actions by the NATO Science Committee. b. Identifying and helping to recruit outstanding persons to head up one or two study groups. c. Assisting in bringing about better interchange of scientific personnel between the U. S. and NATO countries, starting in fields of low security sensitivity. Nuclear Weapons Tests (Item 2) Dr. Carson Mark of the AEC Los Alamos Scientific Laboratory reported on the results of the Hardtack series and their implication on availability of weapons in various weight classes, including clean weapons. He also reported on the results of a LASL study on induced radioactivity associated with ground bursts of clean weapons. The significant points covered were the availability of warheads with expected yields in the 300 and 600 pound weight classes, a 25% reduction in yield expected in the 1600 pound warheads and unavailability of clean weapons in the lower weight range. It was also significant that the LASL study of induced activity showed radioactivity equivalent to 20% fission yield for a ground burst on "standard" ground. (Ref.: Letter from H. A. Bethe to C. Mark, 5/28/58, Secret-Restricted Data.) Atomic Clock Experiment ACTION: The Committee was not enthusiastic about proposing this type of cooperation at the present relatively less advanced state of U. S. rocketry. YH BY UdsNUOddsaY There was general discussion of the suggestion by Dr. Zacharias that the U. S. enter into a cooperative program with the USSR for the launching of atomic clocks to test out experimentally certain aspects of the theory of relativity. ee eot® “ar AQVGUL GAAMVUUNYADS La U wHULMU wer ROOeT oes eee inne oe mi < ja ee . Sa sat mncas wm a