A three-state radioactive sample. Radionuclides change from red to green to blue as they decay.
A three-state radioactive sample. Radionuclides change from red to green
to blue as they decay.
The Three State Nuclear Decay JavaScript Model extends the Two State Nuclear Decay JavaScript 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. Before the simulation starts, users can set the initial numbers N1 and N2, the decay constants k1 and k2, and the time interval between measurements Δt. The simulation counts the number of decay events ΔN1 and ΔN2 within Δt and stops when all nuclides are in the stable state.
The plot shows the time evolution of the nuclides as well as the number of decay events in each Δt time interval to allow users to compare the data generated by the random decay model with a differential equation-based model as described on the Theory page. The Radioactivity check box switches the view to show the number of decay events ΔN within the Δt interval as described on the Theory page. The Particles check box enlarges the nuclide view.
The Three State Nuclear Decay model was developed by Wolfgang Christian using version 5.2 of the Easy Java/JavaScript Simulations (EjsS) authoring and modeling tool. Although EjsS is a Java program, it creates ready-to-run JavaScript simulations and ePubs. Information about EJS is available at: < http://www.um.es/fem/Ejs/> and in the OSP ComPADRE collection < http://www.compadre.org/OSP/>.