20 research outputs found
The lowest order inelastic QED processes at polarized photon-electron high energy collisions
The compact expressions for cross sections of photoproduction of a pair of
charged particles ; ; as
well as the double Compton scattering process are given. The explicit analytic
expressions for the case of polarized photon and the initial electron in the
kinematics when all the particles can be considered as a massless ones are
presented. The photon polarization is described in the terms of Stokes
parameters.Comment: LaTeX2e, 9 page
Radiative corrections in decay
The final state interaction of pions in the decay allows to obtain the value of the isospin and angular
momentum zero pion-pion scattering length . To extract this quantity
from experimental data the radiative corrections (RC) have to be taken into
account. Basing on the lowest order results and the factorization hypothesis,
we get the expressions for RC in the leading and next-to leading logarithmical
approximation. It is shown that the decay width dependence on the lepton mass
through the parameter
\sigma=\frac{\alpha}{2\pi}\br{\ln\frac{M^2}{m_e^2}-1} has a standard form of
the Drell-Yan process and is proportional to the Sommerfeld-Sakharov factor.
The numerical estimations are presented.Comment: 11 pages, 5 figures, 1 table, some minor misprints are correcte