IV IPARCOS Congress

Understanding large local CP violation in B± → K±π+π− using dispersive methods

10 Dec 2025, 15:35

13m

Aula Magna M1 (Facultad de Ciencias Físicas, UCM)

Oral presentation Short contributions

Speaker

Alba Reyes Torrecilla (Universidad Complutense de Madrid and IPARCOS)

Description

We utilize the universality of pion–pion (ππ) final-state interactions at small invariant masses to understand the enhanced local CP violation in B± → K±π+π−, using a dispersive approach. From a fit to the integrated CP-asymmetry data, we successfully predict the Dalitz-plot kinematic distribution of the asymmetry in the low-energy ππ region, including the large local CP violation recently observed by LHCb. An essential role is played by the contributions of isospin 2. This formalism, whose parameters have a physical meaning, can be adapted straightforwardly to other systems with CP violation enhanced by final-state interactions.

Presentation materials

ReyesTorrecila_Alba_Congreso_IPARCOS_2025.pdf