Detection and mapping of decoupled stellar and ionized gas structures in the ultraluminous infrared galaxy IRAS 12112+0305

Integral field optical spectroscopy with the INTEGRAL fiber-fed system and Hubble Space Telescope optical imaging are used to map the complex stellar and warm ionized gas structure in the ultraluminous infrared galaxy IRAS 12112+0305. Images reconstructed from wavelength-delimited extractions of the...

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Detalles Bibliográficos
Autores: Colina, Luis, Arribas-Mocoroa, Santiago, Borne, Kirk D., Monreal-Ibero, Ana
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2000
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/199146
Acceso en línea:http://hdl.handle.net/10261/199146
Access Level:acceso abierto
Palabra clave:Galaxies: active
Galaxies: individual (IRAS 1211210305)
Galaxies: interactions
Galaxies: nuclei
Galaxies: starburst
Descripción
Sumario:Integral field optical spectroscopy with the INTEGRAL fiber-fed system and Hubble Space Telescope optical imaging are used to map the complex stellar and warm ionized gas structure in the ultraluminous infrared galaxy IRAS 12112+0305. Images reconstructed from wavelength-delimited extractions of the integral field spectra reveal that the observed ionized gas distribution is decoupled from the stellar main body of the galaxy, with the dominant continuum and emission-line regions separated by projected distances of up to 7.5 kpc. The two optical nuclei are detected as apparently faint emission-line regions, and their optical properties are consistent with being dust-enshrouded weak [O I] LINERs. The brightest emission-line region is associated with a faint (m1 = 20.4), giant H II region of 600 pc diameter, in which a young (∼5 Myr) massive cluster of about 2 × 107 M⊙ dominates the ionization. Internal reddening toward the line-emitting regions and the optical nuclei ranges from 1 to 8 mag in the visual. Taking the reddening into account, the overall star formation in IRAS 12112+0305 is dominated by starbursts associated with the two nuclei and corresponds to a star formation rate of 80 M⊙ yr-1.