Radiative Decays and QED Corrections to Weak Decay Amplitudes

by Christopher Sachrajda (Uni. Southampton)

Tuesday 16 Jun 2026, 16:00 → 17:00 Europe/Berlin

D 308 (ENC)

Lattice QCD results for some physical quantities are now so precise that isospin-breaking effects, including in particular QED corrections, need to be included to make further progress in precision tests of the Standard Model and in determining CKM matrix elements. I will review the current status of including QED corrections in finite-volume Euclidean lattice computations and discuss the “Cabibbo Angle Anomaly”, the tension in the unitarity of the first row of the CKM matrix.

An important related class of processes are the radiative decays of pseudoscalar mesons, $P\to\ell\nu_\ell\gamma$ and $P\to\ell\nu_\ell(\ell^{+\prime} \ell^{-\prime})$. I will review the latest lattice predictions and compare them to experimental results from the KLOE(Frascati), E36(JPARC) and NA62(CERN) collaborations.

Novel techniques implemented in the above studies include “Infinite-Volume Reconstruction” and “Spectral Function Reconstruction”.