The Three State Nuclear Decay model extends the Two State Nuclear Decay model to simulate the radioactive decay of atomic nuclei in which the parent nucleus first decays into an intermediate state before decaying into a stable state. Although the decay of both the parent and intermediate nucleus (radionuclides) is spontaneous and unpredictable, the probability of decay of each  radionuclide is constant and is usually known.  The model displays a color-coded sample with N1 parent nuclides, N2 intermediate state nuclides, and N3 stable state nuclides.  Users can set the initial numbers N1 and N2, the decay the decay constants k1 and k2, and the time interval between measurements Δt before the simulation is run. The simulation counts the number of decay events and stops when all nuclides are in the stable state.
 
Check boxes display a plot and a table showing the time evolution of each state as well as the number of decay events in each time interval.  The data plot allows users to compare the data generated by the random decay model with a differential equation-based model.


The Three State Nuclear Decay model was developed using the Easy Java Simulations (Ejs) modeling tool.  It is distributed as a ready-to-run (compiled) Java archive.  Double clicking the ejs_nuclear_ThreeStateNuclearDecay.jar file will run the program if Java is installed.

Please note that this resource requires at least version 1.5 of Java.