#rds-1

[nelc]

Russia's first atomic bomb, the RDS-1

[nuclearvault]

Pervaya Molniya (RDS-1) (1949) Semipalatinsk Test Site (Semipalatinsk, Kazakh SSR) 22 kilotons

RDS-1, codenamed Joe-1 by the United States in reference to Joseph Stalin, was used in the Soviet Union's first nuclear weapon test.

[supercriticality]

The Soviet Union became a nuclear state in 1949 with it's first test codenamed "Lighting Joe", the RDS-1 bomb. It was very similar to the Fat Man as Soviet spies at the time had successfully stolen the design.

As a result of using the Fat Man's design, it was a Plutonium core and had a yield of 22kt.

The SU very quickly moved on to Thermonuclear weapons development by their 4th nuclear test in 1953 with the RDS-6 bombs. These weren't "true" fusion devices however, since they obtained most of their yield from fission reactions.

Some design notes:

The RDS-6s used a U-235 fissile core surrounded by alternating layers of fusion fuel (lithium-6 deuteride spiked with tritium), and fusion tamper (natural uranium) inside a high explosive implosion system. The small U-235 fission bomb acted as the trigger (about 40 kt). The total yield was 400 Kt, and 15-20% of the energy was released by fusion, and 90% due directly or indirectly to the fusion reaction.

Lots more here: http://nuclearweaponarchive.org/Russia/Sovwpnprog.html

[spssky]

 Izdeliye 501