Astrophysical: Planetary nebulae

  • Publication
    Chemical abundances of Planetary Nebulae in M 33
    Using spectroscopic data presented in Magrini et al. (cite{m03}), we have analyzed with the photoionization code CLOUDY 94.00 (Ferland et al. cite{ferland}) 11...
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    Chemical Abundances of Planetary Nebulae in the Substructures of M31. II. The Extended Sample and a Comparison Study with the Outer-disk Group
    We report deep spectroscopy of 10 planetary nebulae (PNe) in the Andromeda Galaxy (M31) using the 10.4 m Gran Telescopio Canarias (GTC). Our targets reside in...
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    Chemical behavior of the dwarf irregular galaxy NGC6822. Its PN and HII region abundances
    Aims: We aim to derive the chemical behavior of a significant sample of PNe and HII regions in the irregular galaxy NGC 6822. The selected objects are...
  • Publication
    Chemistry in the dIrr galaxy Leo A
    We present chemical abundance determinations of two H II regions in the dwarf irregular (dIrr) galaxy Leo A from Gran Telescopio Canarias (GTC) Optical System...
  • Publication
    Circumstellar PAHs in IRAS 16594-4656: a new proto-planetary nebula with a strong 21mum dust feature
    Based on ISO SWS+LWS observations, we identify IRAS 16594-4656 as a new member of the rare class of C-rich proto-planetary nebulae with the 21 μm dust feature...
  • Publication
    Close binary central stars and the abundance discrepancy - new extreme objects
    Recent work (Corradi et al. 2015; Jones et al. 2016) has shown that the phenomenon of extreme abundance discrepancies, where recombination line abundances...
  • Publication
    CO content of bipolar planetary nebulae
    We report high-sensitivity millimeter-wave CO observations of recently discovered bipolar planetary nebulae (PNe). Three objects (BV 5-1, K 3-94 and K 3-24)...
  • Publication
    Co-spatial Long-slit UV/Optical AL Spectra of 10 Galactic Planetary Nebulae with HST/STIS. I. Description of the Observations, Global Emission-line Measurements, and CNO Abundances
    We present observations and initial analysis from a Hubble Space Telescope (HST) Cycle 19 program using STIS to obtain the first co-spatial, UV–optical spectra...
  • Publication
    Co-spatial Long-slit UV/Optical Spectra of Ten Galactic Planetary Nebulae with HST/STIS. II. Nebular Models, Central Star Properties, and He+CNO Synthesis
    The goal of the present study is twofold. First, we employ new HST/STIS spectra and photoionization modeling techniques to determine the progenitor masses of...