Generic calculation of two-body partial decay widths at the full one-loop level.

Area of Science:

• High Energy Physics
• Theoretical Physics
• Computational Physics

Background:

• Precise theoretical predictions for particle decays are crucial for testing fundamental physics models.
• Existing computational tools often lack generality or full one-loop precision for diverse particle physics models.

Purpose of the Study:

• To implement a fully generic, one-loop calculation of two-body partial decay widths.
• To provide a framework compatible with various theoretical models, including the Standard Model and the Minimal Supersymmetric Standard Model (MSSM).

Main Methods:

• Development of generic expressions for virtual and real corrections at the full one-loop level.
• Implementation of renormalization schemes (e.g., on-shell, $\overline{\text{DR}}$) and model-specific counter-terms.
• Procedure for canceling infrared divergences using infrared counter-terms and corrected Goldstone boson vertices.

Main Results:

• Successful implementation of fermionic and scalar decays at full one-loop precision.
• Validation against established codes (SFOLD, FVSFOLD, HFOLD, CNNDecays) for MSSM and R-parity violating models.
• Demonstration of renormalization of electric charge in Standard Model top-quark decays.

Conclusions:

• The SARAH 4.11.0 framework now includes comprehensive one-loop two-body decay width calculations.
• The implemented methods offer enhanced accuracy and broader applicability for theoretical particle physics research.
• The framework facilitates precise comparisons between theoretical predictions and experimental observations.