Intense laser pulses can couple resonances in the continuum, giving rise to a
split pair of autoionizing polaritons whose lifetime can be extended as a
result of interference between radiative and Auger decay channels. We present
an extension of the Jaynes-Cummings model to autoionizing states which
quantitatively reproduces this phenomenology and allows us to study how the
dressing laser parameters can be tuned to control the ionization rate of the
polariton multiplet. We illustrate the potential of this model to estimate the
splitting and widths of the polaritonic features in the attosecond
transient-absorption spectrum of the argon atom in the energy region close to
the 3s−1nℓ autoionizing states and compare the results with ab initio
simulations of the spectrum in realistic experimental conditions.Comment: 15 pages, 13 figure