  A variant of the Anderson model, that describes hybridization between
localized state (c-state) of a quantum dot and a Fermi sea conduction band, is
investigated. We demonstrate that, as a function of the hybridization parameter
v, the system undergoes a crossover from the state where the conduction band
and the c-level are fully coupled to a state where these are decoupled. The
c-electron spectrum, however, has a gap together with the presence of the Kondo
peak in the former state. For the latter, we have a Mott-like localization
where the c-electron spectrum again has a gap without the Kondo peak. Within
this gap the conduction electrons fully recover the free band density of states
and the effective hybridization is practically zero. Our main aim, however, is
to study the emission and absorption in a quantum dot with strongly correlated
Kondo ground state. We use the Green function equation of motion method for
this purpose. We calculate the absorption/emission (A/E) spectrum in the Kondo
regime through a symmetrized quantum autocorrelation function obtainable
directly within perturbation theory using the Fermi golden rule approximation.
The spectrum reveals a sharp, tall peak close to Kondo-Abrikosov-Suhl peak and
a few smaller, distinguishable ones on either side. The former clearly
indicates that the Kondo phenomenon has its impact on A/E (non-Kondo
processes), which are driven by the coupling involving the dipole moment of
quantum dot transitions reflecting the physical structure of the dot including
the confinement potential, in the Kondo regime.
