Uranium 238 is not fissile. When bombarded with thermal neutrons it becomes Plutonium 239 which is fissile. However, I have read that U238 nucleus can split apart if bombarded with energetic fast moving neutrons. My question is, when bombarded with fast neutrons what exactly would be the fission products when U 238 splits apart, as U235 may split into barium and krypton?
[Physics] What are the fission products of Uranium 238
nuclear-physicsradiation
Related Solutions
They don't. Here's a figure from Wikipedia:
Typically there's daughter with mass around 95, a daughter with mass around 140, and two or three extra free neutrons. In discussion of environmental contamination after nuclear accidents, you hear a lot about iodine-133 and strontium-90, because they are relatively long-lived and biologically active. Iodine-133 lives for about a week and accumulates in the thyroid; strontium-90 lives for about 30 years and can replace calcium in bones.
There are several heavy isotopes which can spontaneously fission; the big ones are uranium, plutonium, and californium.
Best Answer
It's surprisingly hard to find this information. Presumably it's because U238 fission is of no commercial importance. Anyhow, the data can be found on the International Atomic Energy Agency web site.
The fast neutron fission can go via many different paths and there are many daughter products. For convenience I have sorted the data on the linked web page in descending order of fission product abundance:
This shows only the most abundant fission products as there are dozens of products with tiny abundances.
In general when you use fast neutrons you're going to get a messy fission process as there is lots of spare energy around to be randomly distributed around the nucleons.