A study of extragalactic planetary nebulae populations based on spectroscopy. I. Data compilation and first findings

Delgado-Inglada, G.; García-Rojas, J.; Stasińska, G.; Rechy-García, J. S.
Referencia bibliográfica

Monthly Notices of the Royal Astronomical Society

Fecha de publicación:
9
2020
Número de autores
4
Número de autores del IAC
1
Número de citas
4
Número de citas referidas
4
Descripción
We compile published spectroscopic data and [O III] magnitudes of almost 500 extragalactic planetary nebulae (PNe) in 13 galaxies of various masses and morphological types. This is the first paper of a series that aims to analyse the PN populations and their progenitors in these galaxies. Although the samples are not complete or homogeneous, we obtain some first findings through the comparison of a few intensity line ratios and nebular parameters. We find that the ionized masses and the luminosities in H β, LH β, of around 30 objects previously identified as PNe indicate that they are most likely compact H II regions. We find an anticorrelation between the electron densities and the ionized masses in M 31, M 33, and NGC 300 that suggests that most of the PNe observed in these galaxies are probably ionization bounded. This trend is absent in LMC and SMC suggesting that many of their PNe are density bounded. The He II λ4686/H β values found in many PNe in LMC and some in M 33 and SMC are higher than in the other galaxies. Photoionization models predict that these high values can only be reached in density bounded PNe. We also find that the brightest PNe in the sample are not necessarily the youngest since there is no correlation between electron densities and the H β luminosities. The strong correlation found between LH β and $L_{[\rm {O}\, \small {III}] }$ implies that the so far not understood cut-off of the planetary nebula luminosity function (PNLF) based on [O III] magnitudes can be investigated using LH β, a parameter much easier to study.
Proyectos relacionados
Izquierda - Imagen RGB de la nebulosa de Orión y M43 obtenida filtros estrechos con la cámara WFC en el INT: H alfa (rojo), [S II] 6716+30 (verde), [O III] 5007 (azul). Derecha - Imagen en falso color de la nebulosa planetaria NGC 6778. En azul se ve la emisión en la línea de O II tomada con el filtro sintonizable azul del instrumento OSIRIS en el GTC; en verde imagen con el filtro estrecho de [O III] del Nordic Optical Telescope (NOT).
Física de Nebulosas Ionizadas
Este proyecto mantiene dos líneas principales de investigación activas: 1) Estudio de la estructura, condiciones físicas y composición química de las nebulosas ionizadas, tanto galácticas como extragalácticas, a través del análisis detallado y modelización de sus espectros. Investigación de los gradientes de composición química a lo largo del disco
Jorge
García Rojas