Invisibles25 Workshop

Session

Poster Session & Reception

1 Sept 2025, 17:30

500/1-001 - Main Auditorium (CERN)

169. Maximal CP violation from long-range forces

Anna Socha (LPENS & Sorbonne University)

Poster

In many theoretical models, the observed matter-antimatter asymmetry originates from out-of-equilibrium decays and scatterings of heavy particles. In these scenarios, charge-parity (CP) symmetry violation arises perturbatively through the interference between tree-level and one-loop diagrams. As a result, the CP asymmetry, characterized by the parameter $\epsilon$, is suppresed by higher...

65. Rekindling s-Wave Dark Matter Annihilation Below 10 GeV with Breit-Wigner Effects

Margaux Jomain (LAPTh)

Poster

Thermal Dark Matter (DM) below the GeV scale faces strong cosmological and astrophysical constraints, with Cosmic Microwave Background (CMB) observations excluding s-wave annihilation cross-sections for thermal DM below 10 GeV. Such limits can be evaded with velocity dependent cross-sections, for example when DM annihilates near a narrow resonance. In this work, we explore the impact of...