Infrared Imaging and Optical Imaging and Spectroscopy of (mostly) type I Planetary Nebulae II
Optical spectra, images in the main optical emission lines and IR images directedtowards the detection of molecular hydrogen, were obtained for 14 planetarynebulae (PNe). Eleven of these comply with the two criteria defining a type I PNe(He-rich with a large N/O ratio). All are classified as bipolar...
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2003 |
| País: | México |
| Institución: | Universidad Nacional Autónoma de México |
| Repositorio: | Redalyc-UNAM |
| OAI Identifier: | oai:redalyc.org:57139202 |
| Acceso en línea: | https://www.redalyc.org/articulo.oa?id=57139202 |
| Access Level: | acceso abierto |
| Palabra clave: | Física, Astronomía y Matemáticas 22) 3: SH1 89: WRAY16 ISM: PLANETARY NEBULAE ISM: INDIVIDUAL (A 24: A79: KJPN6: M3 |
| Sumario: | Optical spectra, images in the main optical emission lines and IR images directedtowards the detection of molecular hydrogen, were obtained for 14 planetarynebulae (PNe). Eleven of these comply with the two criteria defining a type I PNe(He-rich with a large N/O ratio). All are classified as bipolar, though two of them(A 24 and M3-5) are either bipolars seen pole-on or elliptical. Shocked molecularhydrogen was detected in eight of these objects, but not in A14, A24, and M1-57.KjPn 6 was tentatively classified as a type I PN, though its helium abundance issmaller than the minimum prescribed value and the sum of its nitrogen and oxygenabundances is low. The object is about 800 pc above the galactic plane, isbipolar and shows no trace of molecular hydrogen. The chemical composition ofA24, A79, M1-57, and Sh 1-89 indicates that third dredge-up episodes occured intheir progenitor star. Shock waves are propagating in the ionized component ofA79, M1-28 and NGC2818, and possibly A14, A24, and K3-46. An emission arcin the periphery of Wray 16-22, a type III PN, may be interpreted as a bow shockproduced by the supersonic motion of this object in the interstellar medium. |
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