Speaker
Alexander Khodjamirian
(University of Siegen)
Description
Our ability to trace new physics in the $c\to u\ell^+\ell^-$ transitions
by measuring the $D\to\pi\ell^+\ell^-$ decay width
critically depends on the accurate knowledge of this decay amplitude,
dominated by an overlap of a singly Cabibbo suppressed weak decay and
electromagnetic lepton pair emission.
We calculate this amplitude, combining LCSRs with
hadronic dispersion relation, and present our preliminary results for the
differential width. We also demonstrate that an additional knowledge
can be gained, measuring Cabibbo favoured and doubly suppressed
$D_{(s)}\to P\ell^+\ell^-$ modes ($P=\pi,K,\eta$) which share common hadronic dynamics with
$D\to \pi\ell^+\ell^-$ and are also related to the latter by the U-spin
symmetry.
Primary author
Alexander Khodjamirian
(University of Siegen)
