Using the VLT to analyze the compact photoionized regions in NGC 3109

From ESO VLT \on-band o-band" imaging of the dwarf irregular - late type spiral NGC3109, we have detected20 planetary nebula (PN) candidates and many compact HII regions all over the galaxy. PN candidates havebeen selected as stellar objects with no detectable (or very faint) stellar continuum....

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Detalles Bibliográficos
Autores: M. Peña, M. G. Richer, G. Stasinska
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:México
Institución:Universidad Nacional Autónoma de México
Repositorio:Redalyc-UNAM
OAI Identifier:oai:redalyc.org:57102921
Acceso en línea:https://www.redalyc.org/articulo.oa?id=57102921
Access Level:acceso abierto
Palabra clave:Física, Astronomía y Matemáticas
HII REGIONS
PLANETARY NEBULAE
GALAXIES: INDIVIDUAL (NGC 3109)
Descripción
Sumario:From ESO VLT \on-band o-band" imaging of the dwarf irregular - late type spiral NGC3109, we have detected20 planetary nebula (PN) candidates and many compact HII regions all over the galaxy. PN candidates havebeen selected as stellar objects with no detectable (or very faint) stellar continuum. Further spectroscopy (withVLT FORS multi-object) in the 3700-6800 A range has confirmed the PN nature of several candidates. Most ofthe PNe appear as low excitation nebulae. Spectra were also acquired for several HII regions. For many objectsthe [O III] 4363 line, sensitive to electron temperature, was detected, allowing a trustworthy determination ofchemical abundances. Therefore a comparative analysis of chemical composition in both type of objects canbe performed. We find that the HII regions present very similar O/H abundances (in average 12 + log O/H =7.79 0.10), while O/H in PNe spreads in a larger range. Most of the PNe seem to be O-enriched.