Studies are made on electromagnetic field excitation by a charged particle bunch, entering a half infinite metal waveguide, filled up by a dielectric material. The wave-guide end-face through which the bunch comes in is closed off by
a metal wall. Such situations are considered when the Vavilov-Cherenkov radiation emission condition is fulfilled
and when this radiation emission is absent. Using a method, employed earlier in the study of electromagnetic signal
propagation in the ionosphere, precise analytical expressions are obtained for the fields, containing the Lommel
function from two variables. Excited field spatial pictures are presented, as obtained via numeric calculations for
different values of the bunch energy and kind shape as well as permittivity. The boundary influence is studied on
the wake-field excitation by a resonance bunch chain. It is shown that oscillations with a broad are excited in the
semi-bounded wave-guide in the Cherenkov resonance absence.
