If you deal with ionizing radiation, natural background is a free and always available source.

You could also search in the internet for Monte Carlo codes, for instance....

Perhaps could be useful to read the following documents:

1-A Fast Monte Carlo Algorithm to Simulate the Spectrum of DNA Damages Formed by Ionizing Radiation.

2-www.radiationsimulation.com/simulator.php/simulated-contamination

3- https://www.cdc.gov/nceh/radiation/ionizing_radiation.html

To perform simulations on a working dosimeter, you should check specialized monte-carlo codes such as FLUKA, Geant4 or MCNP, you can estimate the response of the dosimeter when irradiated by various sources.

Порівняйте дослідження опромінювання на двох групах тварин й використанням вашого дозиметра й відомого дозиметра

Which kind of doses, and which radiation qualities (X-rays? Which energies?) are you looking for. You may use a diagnostic, or a therapeutic device, where the doses are very well defined.

WD

Looking at your profile, I am led to assume that you want to make a numerical simulation of a dosimeter, not an experimental one.

Although there are also deterministic simulation codes, Monte Carlo codes are more popular and usually more flexible, and lead to reliable results provided you choose the appropriate options for your problem.

MCNP is popular but not free-access. Other well-known codes are GEANT or FLUKA which can be downloaded . EGS5 can also be considered, if your dosimeter is only sensitive to photons an electrons.

These codes will give you the simulation of the energy deposition in the dosimeter. Specific options may give more about the dosimeter response, like charge collection or luminescence emitted, but often you must rely for that on some experimental calibration, either your own measurements, or data from the litterature.

MCNP

Dear Aravinth,

Are you performing these studies as an academic question or are these detectors meant to be implemented in a radiation protection program?