1083 



U.S. PARTICIPATION AT CERN 



137 



GARGAMELLE received the support that was to lead to the identifica- 

 tion of weak neutral currents. On the negative side, we must count the 

 invitation to an entire U.S. team of experimenters that attempted to do a 

 major experiment at the CERN PS, using almost exclusively equipment 

 built in the United States and transported to CERN, in a search for the 

 relative parities of the sigma and lambda hyperons through spark 

 chamber techniques. This concerted effort to do an entire project from 

 the outside on a go-it-alone basis did not lead to success and would in- 

 fluence later attitudes toward experimental collaborations with 

 nonmember states. 



Also into this period falls the decision by Weisskopf to build the ISR, 

 permitting high-energy protons to interact with others of equal but op- 

 posite momentum; parallel initiatives at BNL had been rejected. The 

 technical success and experience thus gained permitted his successors 

 Leon van Hove and John Adams, in 1978, to support the conversion of 

 the SPS into a proton-antiproton collider, whose great later successes 

 would otherwise be unthinkable. 



The presence of U.S. physicists at CERN thereafter remained a persis- 

 tent but ad personam feature for years, until, with the advent of the 

 above-mentioned ISR in 1971, CERN had a unique facility at its disposal 

 that had no equivalent in the United States. At that point, discussions 

 between Bernard Gregory and Rodney Cool of Rockefeller University, 

 who had spent repeated periods at CERN, led to the entry of U.S. teams 

 into joint experimental ventures at the ISR. The pattern informally sug- 

 gested by Gregory, never elevated into a fixed rule, implied that there 

 should be at most 50-50 participation from the United States and that 

 there should be a proportionate sharing of the costs of experimental 

 equipment, but no charges for services, setup, or beamtime (as has been 

 the case at other laboratories). The ensuing CERN-Columbia- 

 Rockefeller collaboration has, with modifications, existed ever since. It 

 was later joined by a Brookhaven-Yale-Syracuse contingent for another 

 major ISR experiment series, whose head, W. Willis of Yale and 

 Brookhaven, has since become a permanent CERN staff member and by 

 a major search for high-mass states that might decay into ^ + /x~ pairs, 

 headed by S. Ting of MIT. In fact, in 1978, about 25 percent of all 

 physicists working on experiments at the ISR came from U.S. 

 laboratories. All of this happened simply by arrangement with the in- 

 dividual U.S. institutions, not by Council negotiations with U.S. 

 government agencies. 



The CERN Theory Division has similarly benefited from its frequent 

 U.S. contacts and from the inclusion of European returnees from the 

 United States among its staff. Much of European theory tradition tends 



