Intern
RTG 2994 Particle physics at colliders in the LHC precision era

MSc. Abderahmane Maiza and MSc. Aryan Borkar

Julius-Maximilians-Universität Würzburg

T a l k : 15. January 2026

An introductory overview to Sommerfeld enhancement 

The Sommerfeld enhancement is a quantum mechanical effect that arises when slowly moving particles interact through a long-range attractive potential, leading to an increase in their annihilation cross sections compared to standard perturbative predictions. This effect is particularly relevant in indirect dark matter searches, for example in scenarios proposed to explain observed excesses in cosmic-ray electron and positron fluxes which could arise from a large dark matter annihilation cross section into electron-positron pairs.

In this talk, a quantitative description of the Sommerfeld enhancement is presented , followed by a qualitative discussion of its behavior for a Yukawa potential. The second part will introduce the basic framework of bound‑state formation and then describe, at a qualitative level, how quasi‑bound resonant states emerge in the two‑body spectrum when massive particles interact through a Yukawa‑type potential.