Speaker
Dr
Kirill Semenov-Tian-Shansky
(CPHT Ecole Polytechnique, LPT Orsay)
Description
The concept of generalized parton distributions (GPDs),
non-diagonal matrix elements of quark-antiquark or gluon-gluon
non local operators on the light cone, has recently been extended
to baryon to meson and (and baryon to baryon)
transition distribution amplitudes (TDAs), non diagonal matrix elements
of three quark operators between two hadronic states of different baryon number
(or between a baryon state and a photon).
These objects are useful for the description of exclusive processes characterized by
a baryonic exchange such as backward deeply virtual Compton scattering
backward electroproduction of mesons or proton-antiproton annihilation.
Nucleon to meson TDAs are also considered to be a useful tool to quantify the pion cloud in the baryons.
In this talk we address the problem of construction
of a spectral representation of baryon to meson (and baryon to photon) transition distribution amplitudes.
We introduce the notion of quadruple distributions and generalize A. Radyushkin's
factorized Ansatz for this issue.
This allows the modeling of baryon to meson and baryon to photon TDAs
in the complete domain of their definition and quantitative
rate estimates in various hard exclusive reactions.
Primary author
Dr
Kirill Semenov-Tian-Shansky
(CPHT Ecole Polytechnique, LPT Orsay)
Co-authors
Prof.
Bernard Pire
(CPHT Ecole Polytechnique)
Prof.
Lech Szymanowski
(Institute for Nuclear Studies, Warsaw, Poland)
