Speaker
Prof.
Christopher Sachrajda
(University of Southampton)
Description
We review the method proposed in [1] to compute electromagnetic effects in
hadronic processes, such as decays, using lattice simulations. The method
can be applied, for example, to the leptonic and semileptonic decays of light
or heavy pseudoscalar mesons. For these quantities the presence of infrared
divergences in intermediate stages of the calculation makes the procedure
much more complicated than is the case for the hadronic spectrum, for which
calculations already exist. In order to compute the physical widths, diagrams
with virtual photons must be combined with those corresponding to the
emission of real photons. Only in this way do the infrared divergences cancel
as rst understood by Bloch and Nordsieck in 1937. We present a detailed
analysis of the method for the leptonic decays of a pseudoscalar meson and
also review the status of exploratory numerical studies.
[1] N. Carrasco, V. Lubicz, G. Martinelli, C. T. Sachrajda, N. Tantalo,
C. Tarantino and M. Testa,
"QED Corrections to Hadronic Processes in Lattice QCD,"
Phys. Rev. D 91 (2015) 7, 074506 [arXiv:1502.00257 [hep-lat]].
Primary author
Prof.
Christopher Sachrajda
(University of Southampton)
