On the production of He, C, and N by low- and intermediate-mass stars: a comparison of observed and model-predicted planetary nebula abundances
The primary goal of this paper is to make a direct comparison between the measured and model-predicted abundances of He, C, and N in a sample of 35 well-observed Galactic planetary nebulae (PNe). All observations, data reductions, and abundance determinations were performed in house to ensure maximu...
Guardado en:
| Autores principales: | , , , , |
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| Formato: | Articulo |
| Lenguaje: | Inglés |
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2018
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| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/93706 https://academic.oup.com/mnras/article-abstract/473/1/241/4107117 https://ri.conicet.gov.ar/handle/11336/82516 |
| Aporte de: |
| id |
I19-R120-10915-93706 |
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| record_format |
dspace |
| institution |
Universidad Nacional de La Plata |
| institution_str |
I-19 |
| repository_str |
R-120 |
| collection |
SEDICI (UNLP) |
| language |
Inglés |
| topic |
Astronomía stars: AGB and post-AGB stars: evolution ISM: abundances planetary nebulae: general galaxies: abundances galaxies: ISM |
| spellingShingle |
Astronomía stars: AGB and post-AGB stars: evolution ISM: abundances planetary nebulae: general galaxies: abundances galaxies: ISM Henry, R. B. C. Stephenson, B. G. Miller Bertolami, Marcelo Miguel Kwitter, K. B. Balick, B. On the production of He, C, and N by low- and intermediate-mass stars: a comparison of observed and model-predicted planetary nebula abundances |
| topic_facet |
Astronomía stars: AGB and post-AGB stars: evolution ISM: abundances planetary nebulae: general galaxies: abundances galaxies: ISM |
| description |
The primary goal of this paper is to make a direct comparison between the measured and model-predicted abundances of He, C, and N in a sample of 35 well-observed Galactic planetary nebulae (PNe). All observations, data reductions, and abundance determinations were performed in house to ensure maximum homogeneity. Progenitor star masses (M ≤ 4M⊙) were inferred using two published sets of post-asymptotic giant branch model tracks and L and T<sub>eff</sub> values. We conclude the following: (1) the mean values of N/O across the progenitor mass range exceeds the solar value, indicating significant N enrichment in the majority of our objects; (2) the onset of hot bottom burning appears to begin around 2 M⊙, i.e. lower than ~5M⊙ implied by theory; (3) most of our objects show a clear He enrichment, as expected from dredge-up episodes; (4) the average sample C/O value is 1.23, consistent with the effects of third dredge up; and (5) model grids used to compare to observations successfully span the distribution over metallicity space of all C/O and many He/H data points but mostly fail to do so in the case of N/O. The evident enrichment of N in PN and the general discrepancy between the observed and model-predicted N/O abundance ratios signal the need for extra mixing as an effect of rotation and/or thermohaline mixing in the models. The unexpectedly high N enrichment that is implied here for low-mass stars, if confirmed, will likely impact our conclusions about the source of N in the Universe. |
| format |
Articulo Articulo |
| author |
Henry, R. B. C. Stephenson, B. G. Miller Bertolami, Marcelo Miguel Kwitter, K. B. Balick, B. |
| author_facet |
Henry, R. B. C. Stephenson, B. G. Miller Bertolami, Marcelo Miguel Kwitter, K. B. Balick, B. |
| author_sort |
Henry, R. B. C. |
| title |
On the production of He, C, and N by low- and intermediate-mass stars: a comparison of observed and model-predicted planetary nebula abundances |
| title_short |
On the production of He, C, and N by low- and intermediate-mass stars: a comparison of observed and model-predicted planetary nebula abundances |
| title_full |
On the production of He, C, and N by low- and intermediate-mass stars: a comparison of observed and model-predicted planetary nebula abundances |
| title_fullStr |
On the production of He, C, and N by low- and intermediate-mass stars: a comparison of observed and model-predicted planetary nebula abundances |
| title_full_unstemmed |
On the production of He, C, and N by low- and intermediate-mass stars: a comparison of observed and model-predicted planetary nebula abundances |
| title_sort |
on the production of he, c, and n by low- and intermediate-mass stars: a comparison of observed and model-predicted planetary nebula abundances |
| publishDate |
2018 |
| url |
http://sedici.unlp.edu.ar/handle/10915/93706 https://academic.oup.com/mnras/article-abstract/473/1/241/4107117 https://ri.conicet.gov.ar/handle/11336/82516 |
| work_keys_str_mv |
AT henryrbc ontheproductionofhecandnbylowandintermediatemassstarsacomparisonofobservedandmodelpredictedplanetarynebulaabundances AT stephensonbg ontheproductionofhecandnbylowandintermediatemassstarsacomparisonofobservedandmodelpredictedplanetarynebulaabundances AT millerbertolamimarcelomiguel ontheproductionofhecandnbylowandintermediatemassstarsacomparisonofobservedandmodelpredictedplanetarynebulaabundances AT kwitterkb ontheproductionofhecandnbylowandintermediatemassstarsacomparisonofobservedandmodelpredictedplanetarynebulaabundances AT balickb ontheproductionofhecandnbylowandintermediatemassstarsacomparisonofobservedandmodelpredictedplanetarynebulaabundances |
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Repositorios |
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1764820491606949890 |