Title: Radial transonic shock solutions of Euler-Poisson system in convergent nozzles,
Abstract: Given constant data of density $\rho_0$, velocity $-u_0{\bf e}_r$, pressure
$p_0$ and electric force $-E_0{\bf e}_r$ for supersonic flow at the entrance,
and constant pressure $p_{\rm ex}$ for subsonic flow at the exit, we prove that
Euler-Poisson system admits a unique transonic shock solution in a two
dimensional convergent nozzle, provided that $u_0>0$, $E_0>0$, and that $E_0$
is sufficiently large depending on $(\rho_0, u_0, p_0)$ and the length of the
nozzle.