Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2009-01-15
Astrophys.J.696:729-740,2009
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
25 pages, 12 figures, ApJ submitted
Scientific paper
10.1088/0004-637X/696/1/729
The Planetary Nebula (PN) population of M33 is studied via multi-fiber spectroscopy with Hectospec at the MMT. In this paper we present the spectra of 102 PNe, whereas plasma diagnostic and chemical abundances were performed on the 93 PNe where the necessary diagnostic lines were measured. About 20% of the PNe are compatible with being Type I; the rest of the sample is the progeny of an old disk stellar population, with main sequence masses M<3M${_\odot}$ and ages t$>$0.3 Gyr. By studying the elemental abundances of the PNe in the M33 disk we were able to infer that: (1) there is a tight correlation between O/H and Ne/H, broadly excluding the evolution of oxygen; (2) the average abundances of the $\alpha$-elements are consistent with those of \hii regions, indicating a negligible global enrichment in the disk of M33 from the epoch of the formation of the PN progenitors to the present time; (3) the radial oxygen gradient across the M33 disk has a slope of -0.031$\pm$0.013 dex kpc$^{-1}$, in agreement, within the errors, with the corresponding gradient derived from HII regions. Our observations do not seem to imply that the metallicity gradient across the M33 disk has flattened considerably with time. We report also the discovery of a PN with Wolf-Rayet features, PN039, belonging the class of late [WC] stars
Magrini Laura
Stanghellini Letizia
Villaver Eva
No associations
LandOfFree
The planetary nebula population of M33 and its metallicity gradient: A look into the galaxy's distant past does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The planetary nebula population of M33 and its metallicity gradient: A look into the galaxy's distant past, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The planetary nebula population of M33 and its metallicity gradient: A look into the galaxy's distant past will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-590141