Program for simulation of radioactive decay.

When the program is started, a radioactive isotope is randomly selected from the database. The chemical symbol of the selected isotope is displayed to the student. The objective is to find the half-life, decay constant, lifetime of a radioactive isotope. Then, using the found half-life, identify a specific isotope of a given element.

The program operates in one of two modes: Half-Life and Decay Constant.

In Half-Life mode, simulation continues until the number of decayed atoms reaches half of the initial number of atoms.

In Decay Constant mode, the simulation continues until the decay time reaches the value set by the user. The decay time can be set between 1 and 10 seconds using the spinner control. You can also enter an arbitrary value in the textbox; to set infinite time leave the textbox blank.

To start the simulation, press the Start button. During the simulation, the atom states are displayed in the viewport; the number of undecayed (remaining) and decayed atoms and the current time are displayed on the corresponding indicators.

To reset all atoms to active (undecayed) state, use the Reset button. It is not necessary to press the Reset button before each start of the simulation: the program performs reset automatically.

To determine the half-life, select Half-Life mode and run the simulation. At the end of the simulation (when half of all nuclei have decayed), the time displayed by the program will be the half-life. Repeat the experiment 10 times. Note that the half-life in each experiment will be slightly different due to the stochastic nature of the process. Find the average half-life (T_1/2).

To determine the decay constant, set mode 2 and decay time to 1 s. Run the experiment and record the number of undecayed atoms N, as well as the natural logarithm of this value ln N. Repeat the experiment for decay times of 2, 3, ... 10 s. The slope of the dependence (ln N(t)) will be equal to the decay constant (lambda). Find the average lifetime (tau=1/lambda) and the half-life (T_1/2=ln2/lambda).

To identify an isotope, open Table of Isotopes and enter the symbol of the element under study in the search bar. Then scroll down to the isotope that has the closest half-life to that determined from the simulation.

The program has multilingual support. Translation into other languages can be done by creating additional resource-only DLLs. The package contains such DLL for Ukrainian language. The procedure how to create localized satellite DLL is described here. To switch language use command line parameter /lang XXX, where XXX is three letter code of language. For example, to set Ukrainian language launch program like this: Decay.exe /lang UKR.

To build the application a Visual Studio 2019 solition is provided.