Poster abstract details
NGC 6826 and NGC 7009: A Unified study of the Planetary Nebulae and their central stars
Abstract
We develop self-consistent stellar-nebular models of NGC~6826 and
NGC~7009. The models reproduce the available observations in the
optical and UV, showing that aditional constrins obtained with this
combined approach to the lead to more trustworthy results. The UV
and optical spectra (920-2000 \AA \hspace{0.1cm} y 3650-6800\AA) of the
central star are modeled with
the atmospheres code CMFGEN. The synthetic spectra is used as input
for the photoionization code CLOUDY, which is then used to reproduce
the optical nebular spectra. The parameters obtained through models are
supplemented with those obtained from the semi-analytical study of
each nebula. The stellar-nebular model allow us to obtain 16
parameters ($T_{\rm eff}$, $log\hspace{0.05cm}g$, $L$, distance,
age, nebular size, etc.) of each nebula and its central star. We
obtained the chemical composition of the star and the nebula
independently. This allows us to develop a comparative study of the
chemical composition in the nebula and the central star. The
analysis of different regions in the nebulae indicates homogeneous
chemical composition. Abundances determined for the stars agree with
those of the nebulae assuming temperature fluctuations
($t^2$$\neq$0.00) in the nebular gas.
NGC~7009. The models reproduce the available observations in the
optical and UV, showing that aditional constrins obtained with this
combined approach to the lead to more trustworthy results. The UV
and optical spectra (920-2000 \AA \hspace{0.1cm} y 3650-6800\AA) of the
central star are modeled with
the atmospheres code CMFGEN. The synthetic spectra is used as input
for the photoionization code CLOUDY, which is then used to reproduce
the optical nebular spectra. The parameters obtained through models are
supplemented with those obtained from the semi-analytical study of
each nebula. The stellar-nebular model allow us to obtain 16
parameters ($T_{\rm eff}$, $log\hspace{0.05cm}g$, $L$, distance,
age, nebular size, etc.) of each nebula and its central star. We
obtained the chemical composition of the star and the nebula
independently. This allows us to develop a comparative study of the
chemical composition in the nebula and the central star. The
analysis of different regions in the nebulae indicates homogeneous
chemical composition. Abundances determined for the stars agree with
those of the nebulae assuming temperature fluctuations
($t^2$$\neq$0.00) in the nebular gas.