I'm very late to this discussion but
@South block @Rajput Lion @D68 @Bon Plan and others, the real yields of Shakti 1 and Shakti 2 were discussed enormously well and in detail by this (I'm assuming American) scientist in a very old website. I'm attaching the link, you guys can read it:
What Are the Real Yields of India's Tests?
Tldr, basically Shakti 2, our pure fission device, was 100% succesful and detonated with a yield of 12 kilotons. However, Shakti 2 was not totally successful, but it did detonated with a likely yield of 31-35 kilotons, which is below BARCs claim of 45 kilotons. The author believes that the primary stage of Shakti 1 performed correctly, but the secondary stage only detonated partially and gave 10-15 kilotons:
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So our hydrogen bomb was NOT a "fizzle" like K Santhanam claims, it did detonate but not upto the desired level. The secondary stage did also detonated but did not provide the expected contribution to the explosion energy. The author thinks that India however can refine the design and indeed develop scaled up version of this device all the way up to 200 kilotons:
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K Santhanam claims that the hydrogen test was a total fizzle and 20 kt of yield came from the Shakti 2 explosion, but evidence shown in the article i shared disprove this, and goes to show Shakti 1 exploded and did explode in a thermonuclear reaction, just that it's level was not upto what was claimed. A partial success imo. And a big one at that, UK a pioneering country in nuclear technology failed multiple times in making hydrogen bombs! They succeeded after multiple failed tests.
I want to remind you guys of 2 key things which people rabidly advocating for testing forget:
1.) Scaling from lower yields is 100% possible, the American W41 was a whopping 25 megatons but was never tested, it was a scaled up version of a 5 megaton weapons iirc. I know we are not America but that was done in 1950s, today India has supercomputers of great complexity, programms to simulate explosions AND data from Shakti tests. It's not implausible to think we can simulate and design 2 stage thermonuclear weapons.
2.) Israel only tested like 1-2 times and has never tested its thermonuclear design and thought that computer simulations are enough. Now some of you may think US would freely give a thermonuclear design to them but imo that's highly unlikely. Thermonuclear weapon is the ultimate weapon of war which is crown jewel of nuclear technology, America didnt even give Israel atom bomb and was against it making it, it tried to stop its Dimon plant construction. So there's no reason to think Israel would get H bomb level of tech from somewhere else.
3.) India most definitely has boosted fission capability, and can boost fission warheads to near or beyond 100 kilotons if needed, which is also an extremely potent deterrent.