Calculating the annihilation rate of weakly interacting massive particles

Area of Science:

• Particle Physics
• Cosmology
• Astrophysics

Background:

• Weakly Interacting Massive Particles (WIMPs) are leading dark matter candidates.
• Annihilation of WIMPs can produce detectable gamma rays.
• Accurate calculation of annihilation rates is essential for WIMP detection.

Purpose of the Study:

• To develop a systematic formalism for calculating WIMP annihilation into high-energy gamma rays.
• To improve upon fixed-order calculations plagued by infrared logarithms.
• To provide a framework for more precise WIMP dark matter searches.

Main Methods:

• Development of a factorization theorem to separate initial-state and final-state radiative corrections.
• Resummation techniques to handle large logarithms beyond fixed order.
• Calculation of the resummed annihilation rate for Majorana WIMPs in the adjoint representation.

Main Results:

• The formalism allows systematic calculation of WIMP annihilation rates into high-energy gamma rays.
• Resummation effects can be significant (~100%) for very heavy WIMPs (20 TeV).
• For thermal relic WIMP masses, resummation modifies Sudakov factors by ~10%, and total radiative corrections are at the percent level.

Conclusions:

• The developed formalism provides a more accurate method for calculating WIMP annihilation signals.
• Radiative corrections, particularly through resummation, are important for precise WIMP studies.
• The formalism is generalizable to other WIMP types and models.