A stochastic cascade model for Auger-electron emitting radionuclides

Area of Science:

• Nuclear Physics and Atomic Physics
• Computational Physics and Modeling

Background:

• Accurate modeling of Auger cascades is crucial for understanding radionuclide decay processes.
• Existing models require validation against established data for reliability in nuclear structure applications.

Purpose of the Study:

• To benchmark a newly developed Monte Carlo model for Auger cascades.
• To assess the model's applicability to Auger-electron emitting radionuclides using nuclear structure data.
• To compare simulated results with existing literature data for iodine isotopes.

Main Methods:

• Incorporation of Schönfeld's algorithms and BrIcc code for initial vacancy distributions (EC and IC).
• Utilization of Evaluated Atomic Data Library (EADL) for atomic transition probabilities (Z=1-100).
• Evaluation of atomic transition energies using a relativistic Dirac-Fock method and implementation of an energy-restriction protocol.

Main Results:

• Calculated initial vacancy distributions and average energy spectra for 123I, 124I, and 125I showed good agreement with literature data.
• Simulated kinetic energy spectra and frequency distributions of emitted electrons and photons were generated.
• Discrepancies were noted primarily in outer-shell Auger and Coster-Kronig transitions.

Conclusions:

• The Monte Carlo Auger cascade model demonstrates good agreement with published data for iodine radionuclides.
• The model is suitable for simulating Auger-electron emission from various radionuclides.
• Future validation against experimental data is recommended to further refine the model.