Nuclear Thread - 4

[ramana]

Hindu Busnessline Article by P.K. Iyengar



Pokhran II revisited

Pokhran-II revisited



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Overall, the question mark over the yield and efficacy of the thermonuclear device, and hence our nuclear deterrent, still remains.





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P. K. Iyengar



In a recent interview with Karan Thapar, the former chief of the Atomic Energy Commission, Dr Anil Kakodkar, reiterated the Principal Scientific Advisor to the Government, Dr R. Chidambaram's stand on the success of Pokhran-II, but did not really address any of the concerns raised about the efficacy of the thermonuclear test. Most of the points he raised in a very general way have been dealt with before in a more detailed technical manner.



Take, for example, the issue about the lack of a crater for the thermonuclear explosion. It is true that if you bury such a device very deep, there will be a very small crater, or even none at all. But no one associated with Pokhran-II has come out with a number for that depth, though there is no secrecy needed here, as it reveals nothing about the design of the device. In fact, for Pokhran-I, we had immediately revealed that the device was buried 107m deep.



Only K. Santhanam, former DRDO scientist, has revealed that the thermonuclear device was buried at a depth of 130m, compared to the fission device's 100m deep location. If these numbers are correct, and no one has contradicted them, it is simply not credible to say that such a small difference in the depth (only 30m) made such a huge difference in the geology or in the crater size.



The repeated assertion that granite in the thermonuclear shaft was responsible for the small crater is also difficult to understand. Usually, shock waves couple better to hard rock and so the effect is expected to be larger. To muffle the explosion, one buries the device in soft material like sand or in an empty cavity. The reverse assertion seems to be a new advance in geology that the CTBT Organisation needs to take note of!



Puzzling statements



Similarly, the statements on the simulations are puzzling. He brought out a new simulation experiment, perhaps done after Dr Santhanam's revelation. Using the borrowed data-base of an underground nuclear explosion in Nevada, they claim to have simulated what would have happened had the fission and fusion devices been interchanged between the two shafts S1 and S2.



He revealed that the fission device would have shown no crater, and the fusion device a much larger crater. This difference in the behaviour between the two sites, 1 km apart, and at almost similar depths, 100 m and 130 m, as revealed by Dr Santhanam, is inexplicable.



Simulations can be tweaked to predict anything you want. Also, there is a huge gap between simulating something and actually making it work in real life. Ultimately, there is no escape from detailed experiments. The computer and the word ‘simulated' have been so extensively used by Dr Chidambaram and others that one wonders if there is any need at all for testing and experimental work in a wide variety of scientific investigations!



I am also disappointed about the implications regarding statements from people not directly associated with Pokhran-II. This suggests that no experts, anywhere in the world, are competent to comment on Pokhran-II! This is unscientific.



One doesn't need to know every detail of the test to make intelligent estimates about the expected yield, or the crater size. In science, anyone can make a scientific observation, and it has to be refuted scientifically, and not by mere assertion. Those who are raising these questions have sufficient knowledge and experience to make those questions pertinent and relevant.



Searching questions



Dr Kakodkar also revealed that we have more then one hydrogen bomb in our arsenal, and that we now have devices with yields ranging from sub-kt to 200 kt.



It must be reassuring to the military to know that the quantity issue has been addressed. But what is more important is to address the quality issue, about which the military should also ask searching questions. After all, deterrence is in the eyes of the enemy; it is not important what a few people assert, but what the whole world thinks.



Overall, I would say that the question mark over the yield and efficacy of the thermonuclear device, and hence our nuclear deterrent, still remains. Right from the beginning, the official response to very legitimate questions, raised by those who are knowledgeable and acting in the best interests of the nation, has been defensive and closed-minded. This does not augur well for the health of our strategic deterrent. Given the strong support from the new US administration for the NPT and the CTBT, and the international pressure that will certainly be put upon India in the near future, this is an issue the Government must address seriously.

Quite well argued. There seems to be an ego trip on the side of the offical group.