New Evidence of Japan's Atom Bomb Program in World War II

On 5 August 2015, Japan's Asahi Shimbun reported on new evidence of Japan's race to create an atomic bomb during World War II. Here are some excerpts from the article by their staff writer Shingo Fukushima:

Earlier this year, notebooks of the late Sakae Shimizu, a professor emeritus at Kyoto University, were discovered by Akira Masaike, 80, professor emeritus of particle physics at Kyoto University, at a library of the school.

Shimizu, a friend of Masaike, is known to have worked as a lecturer under Bunsaku Arakatsu.

Arakatsu, a professor at the department of science of Kyoto Imperial University, the predecessor of Kyoto University, was involved in an Imperial Japanese Navy program to develop an atomic bomb that was code-named “F Research.”...

Masaike said he first became interested in the history of the nuclear weapons program in Japan while staying in the United States between 2004 and 2008....

During the wartime period, the development of centrifuges was under way at Kyoto Imperial University to separate and enrich uranium-235, which is found in uranium ore and is key to generating the chain reaction in nuclear fission....

The documents show the scientists intended to use extra super duralumin, a type of aluminum alloy, to produce a centrifuge....

Those documents revealed the development of the centrifuge was scheduled to be completed Aug. 19, 1945, just days after Japan surrendered to the Allies. Their research was suspended after the end of World War II.