THE 3D VELOCITY STRUCTURE OF THE PLANETARY NEBULA NGC 7009

In search for deviations from homologous expansion in planetary nebulae we present a 3D morphokinematical model of NGC 7009. The model has been constructed with Shape based on PV diagrams from the literature and HST images. We find that the data are consistent with a radial velocity field with incre...

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Detalhes bibliográficos
Autores: Steffen, W, Espindola, M, Martínez, S, Koning, N
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2009
País:México
Recursos:Universidad Nacional Autónoma de México
Repositório:Sistema de Información de la Facultad de Ciencias, UNAM
OAI Identifier:oai:repositorio.fciencias.unam.mx:11154/2193
Acesso em linha:http://hdl.handle.net/11154/2193
Access Level:Acceso aberto
Palavra-chave:Astronomy & Astrophysics
ISM: jets and outflows
planetary nebulae: individual (NGC 7009)
stars: AGB and post-AGB
stars: mass loss
Descrição
Resumo:In search for deviations from homologous expansion in planetary nebulae we present a 3D morphokinematical model of NGC 7009. The model has been constructed with Shape based on PV diagrams from the literature and HST images. We find that the data are consistent with a radial velocity field with increased gradient at high latitudes compared to the equatorial region (Model 1). In a second model we assume a linearly increasing radial velocity Component with ail added poloidal component of order 10 kin s(-1) at latitudes around 70 degrees. The true velocity field is likely to be in between these two limiting cases. We also find that the expansion of the ansae is non-radial with reference to the central star. Their velocity field is focused near the apparent exit points from the main shell. We predict the proper motion pattern for the model with a non-zero poloidal velocity component.