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Follow-Up Near-infrared Spectroscopy of Ultraluminous Infrared Galaxies observed by ISO

H. Dannerbauer·D. Rigopoulou·D. Lutz·R. Genzel·E. Sturm·A. F. M. Moorwood
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Abstract

We present low resolution near-infrared spectroscopy of an unbiased sample of 24 ultraluminous infrared galaxies (ULIRGs), selected from samples previously observed spectroscopically in the mid-infrared with the Infrared Space Observatory (ISO). Qualitatively, the near-infrared spectra resemble those of starbursts. Only in one ULIRG, IRAS 04114-5117E, do we find spectroscopic evidence for AGN activity. The spectroscopic classification in the near-infrared is in very good agreement with the mid-infrared one. For a subset of our sample for which extinction corrections can be derived from Pa-alpha and Br-gamma, we find rather high Pa-alpha luminosities, in accordance with the powering source of these galaxies being star formation.[Fe] emission is strong in ULIRGs and may be linked to starburst and superwind activity. Additionally, our sample includes two unusual objects. The first, IRAS F00183-7111, exhibits extreme [Fe] emission and the second, IRAS F23578-5307, is according to our knowledge one of the most luminous infrared galaxies in H2 rotation-vibration emission.

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H. Dannerbauer, D. Rigopoulou, D. Lutz, R. Genzel, E. Sturm, A. F. M. Moorwood. 2005-08-17. Follow-Up Near-infrared Spectroscopy of Ultraluminous Infrared Galaxies observed by ISO. https://doi.org/10.1051/0004-6361%3A20052812

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