Scientists have developed the first fully microscopic simulation of what occurs when an atom undergoes nuclear fission, or splits in two.
The simulation modeled the fission of uranium-238, plutonium‐240, and californium-252 under different conditions using a national lab supercomputer.
It revealed the fission process occurs in 4 main steps over different timescales: 1) Initial rearrangement in 10-14 seconds, 2) Rapid shifts establishing fragments in 5×10-21 seconds, 3) Official splitting called “scission” in 10-22 seconds, 4) Fragments pull apart and decay over 10-18 seconds.
The simulation provides the most precise theoretical description yet of the “neck rupture” or scission stage without assumptions. It predicts properties of neutrons released during this stage.
Some surprises were found, like an identifiable “wrinkle” in particle density before scission and protons splitting before neutrons.
The next step is experimentally verifying the simulation’s revelations about individual particle behavior during nuclear fission.
Source: ScienceAlert
