Contents I. Introduction
Twenty-five years ago, on September 22, 1993, an event unprecedented in the nuclear age took place at Arzamas-16 (now Sarov), Russia, the location of the All-Russian Scientific Research Institute of Experimental Physics (VNIIEF). A unique scientific experiment was conducted jointly by VNIIEF with its US counterpart, the Los Alamos National Laboratory (LANL). Until then such open, unclassified cooperation between the two institutes that had designed the first nuclear weapons of their respective nations had been impossible due to secrecy and other limitations imposed on the institutes by the political posture of the Cold War. Fortunately, the end of the Cold War, less than two years before the first joint experiment, opened up new possibilities for the former Cold War adversaries, Russia and the US, to work together in a variety of scientific areas. Although leaders of both nations were initially suspicious of the motives of the other, the first joint experiment demonstrated that the two institutes, and, by implication, the two nations, could work together side-by-side as equals in scientific endeavors for mutual benefit. In this paper we describe the first joint experiment and many of the joint scientific accomplishments that followed.
