  Dynamical association of Efimov trimers in thermal gases by means of
modulated magnetic fields has proven very fruitful in determining the binding
energy of trimers. The latter was extracted from the number of remaining atoms,
which featured oscillatory fringes stemming from the superposition of trimers
with atom-dimers. Subsequent theoretical investigations utilizing the
time-dependent three-body problem revealed additional association mechanisms,
manifested as superpositions of the Efimov state with the trap states and the
latter with atom-dimers. The three atoms were initialized in a way to emulate a
thermal gas with uniform density. Here, this analysis is extended by taking
into account the effects of the density profile of a semi-classical thermal
gas. The supersposition of the Efimov trimer with the first atom-dimer remains
the same, while the frequencies of highly oscillatory fringes shift to lower
values. The latter refer to the frequencies of trimers and atom-dimers in free
space since the density profile smears out the contribution of trap states.
