Related papers: Neutron-Capture Element Abundances in Magellanic C…
Neutron(n)-capture elements (atomic number Z>30), which can be produced in planetary nebula (PN) progenitor stars via s-process nucleosynthesis, have been detected in nearly 100 PNe. This demonstrates that nebular spectroscopy is a…
Spectroscopy of planetary nebulae (PNe) provides the means to investigate s-process enrichments of neutron(n)-capture elements that cannot be detected in asymptotic giant branch (AGB) stars. However, accurate abundance determinations of…
We present the chemical abundances of Fe, alpha- and neutron-capture elements in 12 metal-poor Small Magellanic Cloud (SMC) giant stars, observed with the high-resolution spectrographs UVES/VLT and MIKE/Magellan. These stars have [Fe/H]…
We present emission line strengths, abundances, and element ratios (X/O for Ne, S, Cl, and Ar) for a sample of 38 Galactic disk planetary nebulae (PNe) consisting primarily of Peimbert classification Type I. Spectrophotometry for these PNe…
We present six new planetary nebulae (PNe) discovered in the Small Magellanic Cloud (SMC) from deep UK Schmidt telescope (UKST) narrow band Halpha and broad-band short-red "SR" continuum images and confirmed spectroscopically. These 6…
The light element abundance pattern from many planetary nebulae (PNe) covering the upper 4 mag. of the [O III] luminosity function was observed with ESO VLT FORS1 multi-slit. Spectra of 51 PNe over the wavelength range 3500-7500 Angstrom…
Planetary Nebulae (PNe) abundance patterns have long been used to note signatures of nuclear processing and to trace the distribution of metals throughout galaxies. We present abundance gradients and heavy element ratios based upon newly…
We analyze the chemical composition of the planetary nebula (PN) NGC 5315, through high-resolution (R = 40000) optical spectroscopy with UVES at the Very Large Telescope, and medium-resolution (R = 4800) near-infrared spectroscopy with FIRE…
The s-process should occur in all but the lower mass progenitor stars of planetary nebulae, and this should be reflected in the chemical composition of the gas which is expelled to create the current planetary nebula shell. Weak forbidden…
We analyse the planetary nebulae (PNe) population of the Small Magellanic Cloud (SMC), based on evolutionary models of stars with metallicities in the range $10^{-3} \leq Z \leq 4\times 10^{-3}$ and mass $0.9 M\odot < M < 8M\odot$, evolved…
The Magellanic Clouds are close enough to the Milky Way to provide an excellent environment in which to study extragalactic PNe. Most of these PNe are bright enough to be spectroscopically observed and spatially resolved. With the latest…
This paper examines, compares and plots optical, near- and mid-infrared (MIR) photometric data for 605 planetary nebulae (PNe) in the Large Magellanic Cloud (LMC). With the aid of multi-wavelength surveys such as the Spitzer legacy…
New abundances for neutron-capture (n-capture) elements in a large sample of metal-poor giants from the Bond survey are presented. The spectra were acquired with the KPNO 4-m echelle and coude feed spectrographs, and have been analyzed…
This paper presents accurate homogeneous positions, velocities and other pertinent properties for 460 newly discovered and 169 previously known planetary nebulae (PNe) in the central 25 sq deg bar region of the Large Magellanic Cloud (LMC).…
Planetary nebulae (PN) are an excellent laboratory to investigate the nucleosynthesis and chemical evolution of intermediate mass stars. In these objects accurate abundances can be obtained for several chemical elements that are…
We report our initial discovery of 73 new planetary nebulae (PNe) in the Large Magellanic Cloud (LMC) following confirmatory 2dF spectroscopy on the Anglo-Australian Telescope (AAT). Preliminary candidate sources come from a 10 per cent…
We study the relation between the chemical composition and the type of dust present in a group of 20 Galactic planetary nebulae (PNe) that have high quality optical and infrared spectra. The optical spectra are used, together with the best…
We previously determined abundances of He, C, N, O, and Ne for a sample of planetary nebulae (PNe) representing a broad range in progenitor mass and metallicity, and we now compare them with theoretical predictions of PNe abundances from a…
The Large Magellanic Cloud (LMC) contains the nearest large extragalactic population of planetary nebulae (PNe). A shallow viewing angle and low interstellar reddening towards the LMC potentially means a larger, more complete flux-limited…
Planetary nebulae (PN) are an essential tool in the study of the chemical evolution of the Milky Way and galaxies of the Local Group, particularly the Magellanic Clouds. In this work, we present some recent results on the determination of…