Spatially resolved spectroscopic investigation of the born-again planetary nebula A 78

We present the analysis of spatially resolved spectroscopic observations of the born-again planetary nebula (PN) A 78 that are used to investigate the chemistry and physical properties of its three main morphological components, namely the inner knots, its eye-like structure, and the low surface-bri...

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Detalles Bibliográficos
Autores: Montoro-Molina, B., Guerrero, Martín A., Toalá, Jesús A.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/356471
Acceso en línea:http://hdl.handle.net/10261/356471
Access Level:acceso abierto
Palabra clave:(ISM:) planetary nebulae: individual: PN A66 78
(stars:) circumstellar matter
Stars: evolution
Stars: mass-loss
Stars: winds, outflows
Descripción
Sumario:We present the analysis of spatially resolved spectroscopic observations of the born-again planetary nebula (PN) A 78 that are used to investigate the chemistry and physical properties of its three main morphological components, namely the inner knots, its eye-like structure, and the low surface-brightness outer nebula. The H-poor chemical abundances of the inner knots confirm the born-again nature of A 78, with an N/O abundances ratio consistent with the predictions of very late thermal pulses (VLTP). On the other hand, the high Ne/O is not expected in VLTP events, which prompts a possible different evolutionary path may be involving a binary system. The low N/O ratio and He/H abundances of the outer shell are indicative of a low-mass progenitor, whereas the chemical abundances of the eye-like structure, which results from the interaction between the H-poor born-again material and the outer nebula, evidence their mixture. Unlike previous works, the extinction is found to be inhomogeneous, being much higher towards the H-poor inner knots, where the presence of large amounts of C-rich dust has been previously reported. Dust-rich material seems to diffuse into outer nebular regions, resulting in zones of enhanced extinction. © 2023 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society.