A general analysis of polarization phenomena for coherent pion
electroproduction on deuterons is presented.
The spin and isospin structures of the
$\gamma ^{*}+d\to d+P^0$ amplitudes
(where $\gamma ^*$ is a virtual
photon) are established and relationships
between meson electroproduction on
deuterons and on nucleons are given in the
framework of the impulse approximation.
The reaction $e+d\to e+d+\pi^0$ is investigated
in detail, for a relatively large
value of momentum transfer, 0.5 GeV$^2\le -k^2\le$
2 GeV$^2$, both at threshold and in the region
of $\Delta $-isobar excitation. Special attention
is devoted to the sensitivity of different
contributions to the exclusive cross section
for $d(e,e\pi^0)d$, as the
$\gamma^*\pi\omega$ form factor or the
$NN-$potential.
The predicted $k^2$-dependence of
the cross section agrees well with the
available experimental data. |
