The Atomic Energy Commission (AEC) on Tuesday said it had “no reason to doubt the yield of the thermonuclear test carried out on May 11, 1998.”
In a press statement, the AEC said that in its meeting held on September 5, 2009, it discussed recent statements in the media on the thermonuclear test. Of particular concern were the statements made by K. Santhanam, who was a member of the team from the Defence Research and Development Organisation (DRDO) participating in the tests, it said.
The statement said the Commission had been briefed about the successful tests (on May 11 and 13, 1998) at its meeting held on May 21, 1998 wherein, details of the types of the tests, estimated yields and other technical details were given. Some subsequent media reports that appeared to question the reported yields of tests done on May 11, 1998 were discussed at a meeting of the AEC on November 12, 1998.
The Commission had noted at that time that “more recent reports have confirmed the Indian estimate of 60 kilotons for the combined yield of the fission device and the thermonuclear device,” the statement said. Some members of the Commission had felt [then] that the media reports could be more in the form of a disinformation campaign, it added. Later, at the meetings of the AEC held on March 26, 1999 and November 18, 1999, results of the radio-chemical analysis of bore-hole samples, re-confirming the estimated yields, were presented to the Commission.
The statement said: “Dr. Raja Ramanna was then a member of the Atomic Energy Commission and was present at all the meetings referred to above.
“The Atomic Energy Commission notes that the design yield of the thermonuclear test had to be kept at 45 KT in order to protect the nearby Khetolai village from the combined yield of the thermonuclear and the fission test (the two tests had to be necessarily done together as the two shafts were only 1.1 km apart). Close-in instrumentation was deployed. Analysis of the measurements from these instruments as well those from far field instruments located at Gauribidanur (in Karnataka) and several IMD (India Meteorological Department) stations confirmed the combined yield of the two tests to be 58-63 KT. The Commission noted that in the absence of knowledge about local geological conditions, seismic yield assessments could have large variations.
“The yields of the two tests were also confirmed through radiochemical analysis. This work had revealed the estimated yield of the thermonuclear test to be 50 plus or minus 10 KT. The AEC noted that these measurements also gave unambiguous evidence of fusion energy release.
“Finally, the AEC noted that the yield was further reconfirmed through comparison of ground motion and displacement simulation with actual observations in the field.”