De kjernefysiske prøvesprengningene i India og Pakistan (1974 og 1998)

Abstract

On 18 May 1974 and again on 11 May 1998 the world was shocked by Indian nuclear tests. The archrival Pakistan followed on 28 and 30 May 1998. For the 1974 Indian test the official yield is 12 kt. Common literature estimates around 2–5 kt imply a fizzle (failure). Seismic studies at NORSAR in Norway suggest approximately the announced yield. From this, the apparent lack of technical evidence for a low yield, and from the long-time nuclear research and experience in India, we conclude that the 1974 test most likely was a technical success and as announced. Even though most independent yield estimates for the 1998 Indian tests suggests a lower yield than the official values, India probably performed at least some successful detonations. We believe that the claim of a small two-stage thermonuclear device cannot be disregarded, but that a detonation of a two-stage thermonuclear experiment is more likely. Due to its long experience with nuclear devices and alleged outside assistance, Pakistan probably successfully detonated at least some fission devices. The number of Pakistani explosions is probably exaggerated. Pakistan had for a long time shown interest in tritium, and boosting experiments cannot be excluded. India has suggested the same yield estimates for the Pakistani tests as did NORSAR. This suggests that NORSAR’s estimates for the Indian 1974 and 1998 tests are correct. The technical results from the nuclear tests were probably valuable to the two states.