  Using a one-dimensional stellar evolution code we simulate the response of a
red supergiant (RSG) star to injection of energy and to mass removal. We take
the values of the energy that we inject and the mass that we remove according
to our previous three-dimensional hydrodynamical simulations of a neutron star
(NS) on a highly eccentric orbit that enters the envelope of an RSG star for
half a year and launches jets as it accretes mass via an accretion disk. We
find that for injected energies of ~1e47-1e48 erg and removed mass of
~0.03-0.6Mo the RSG envelope expands to a large radius. Therefore, we expect
the NS to continue to orbit inside this massive inflated envelope for several
more months, up to about twice the initial RSG radius, to continue to accrete
mass and launch jets for a prolonged period. Although these late jets are
weaker than the jets that the NS launches while inside the original RSG
envelope, the late jets might actually be more influential on the light curve,
leading to a long, several months to few years, and bright, about >10^8Lo,
transient event. The RSG returns to more or less a relaxed structure after
about ten years, and so another transient event might occur in the next
periastron passage of the NS. Our results add to the already rich variety of
jet-driven explosions/outbursts that might account for many puzzling transient
events.
