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Strong-field manipulation of autoionizing states is a crucial aspect of electronic quantum control. Recent measurements of the attosecond transient absorption spectrum of helium dressed by a few- cycle visible pulse [Ott et al., arXiv:1205.0519[physics.atom-ph] ] provide evidence of novel ultrafast resonant phenomena, namely, two-photon Rabi oscillations between doubly excited states and the inversion of Fano profiles. Here we present the results of accurate ab-initio calculations that agree with these observations and in addition predict that (i) inversion of Fano profiles is actually periodic in the coupling laser intensity and (ii) the supposedly dark 2p2 1S state also appears in the spectrum. Closer inspection of the experimental data confirms the latter prediction.
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