Resonance-enhanced two-photon ionization (RETPI) of Sih II and an anomalous, variable intensity of the lambda-1892 Si III] line in the Weigelt blobs of eta Carinae
Context. The Si III] 1892 angstrom intercombination line shows an anomalously high intensity in spectra of the radiation-rich Weigelt blobs in the vicinity of Eta Carinae. The line disappears during the 100 days long spectral events occurring every 5.5 years. Aims. The aim is to investigate whether resonance-enhanced two-photon ionization (RETPI) is a plausible excitation mechanism for the Si III]