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Abundances in planetary nebulae: NGC1535, NGC6629, He2-108, and Tc1
ISM: abundances – planetary nebulae: individual: NGC1535 & Tc 1 (& IC1266) & NGC6629 & He2-108 – Infrared: ISM: lines and bands
2011/10/12
The aim of the paper is to determine abundances in a group of PNe with uniform morphology. The PNe discussed are circular excited by rather low-temperature central stars. The relation between abundanc...
The formation of fullerenes: clues from new C60, C70, and (possible) planar C24 detections in Magellanic Cloud Planetary Nebulae
formation fullerenes:Magellanic Cloud Planetary Nebulae
2011/10/9
We present ten new Spitzer detections of fullerenes in Magellanic Cloud Planetary Nebulae, including the first extragalactic detections of the C70 molecule. These new fullerene detections together wit...
From Bipolar to Elliptical: Simulating the Morphological Evolution of Planetary Nebulae
From Bipolar Elliptical: Simulating Morphological Evolution Planetary Nebulae
2011/9/27
The majority of Proto-planetary nebulae (PPN) are observed to have bipolar morphologies. The majority of mature PN are observed to have elliptical shapes. In this paper we address the evolution of PPN...
A view of the solar neighbourhood: the local population of planetary nebulae and their mimics
the solar neighbourhood the local population
2011/1/10
We have, for the first time, compiled a nearly complete census of planetary nebulae (PNe) centred on the Sun. Our goal is the generation of an unbiased volume-limited sample, in order to answer some l...
Central Stars of Planetary Nebulae: New spectral classifications and catalogue
Central Stars Planetary Nebulae spectral classifications
2011/1/11
Context. There are more than 3000 true and probable known Galactic Planetary Nebulae (PNe), but only for 13% of them there is central star spectroscopic information available. Aims. To contribute to t...
Imaging "Pinwheel"nebulae with optical long-baseline interferometry
techniques high angular resolution – techniques interferometric – binaries close – stars
2010/11/16
Dusty Wolf-Rayet stars are few but remarkable in terms of dust production rates (up to ˙M = 10−6M⊙/yr). Infrared excesses associated to mass-loss are found in the sub-types WC8 and WC9. Few WC9d...
Fermi-LAT Search for Pulsar Wind Nebulae around gamma-ray Pulsars
catalogs – gamma rays observations – pulsars general
2010/11/12
The high sensitivity of the Fermi-LAT (Large Area Telescope) offers the first opportunity to study faint and extended GeV sources such as pulsar wind nebulae (PWNe). After one year of observation the ...
From pre- to young Planetary Nebulae: radio continuum variability
stars AGB and post-AGB circumstellar matter – radio continuum
2010/11/10
Searching for variability, we have observed a sample of hot post-AGB stars and young Planetary Nebulae candidates with the Very Large Array at 4.8, 8.4, and 22.4 GHz.The sources had been previously de...
Gemini GMOS spectroscopy of HeII nebulae in M33
stars atmospheres — stars Wolf-Rayet — ISM HII regions — ISM lines and bands — galaxies individual (M33)—galaxies
2010/11/15
We have carried out a narrow-band survey of the Local Group galaxy, M33, in the HeII λ4686 emission line, to identify HeII nebulae in this galaxy. With spectroscopic follow-up observations, we confirm...
Radio-continuum detections of Galactic Planetary Nebulae I. MASH PNe detected in large-scale radio surveys
Radio-continuum Galactic Planetary Nebulae I
2011/1/10
We present an updated and newly compiled radio-continuum data-base for MASH PNe detected in the extant large scale "blind" radio-continuum surveys (NVSS, SUMSS/MGPS-2 and PMN) and, for a small number ...
Gamma-rays from Pulsar Wind Nebulae in Starburst galaxies (HEAD 2010)
High Energy Astrophysical Phenomena (astro-ph.HE)
2010/12/29
Recently, two nearby prominent starburst galaxies, M82 and NGC253, have been detected as point-like sources with gamma-ray telescopes at TeV energies [1] [2]. It has been claimed that these detections...
Gamma-rays from pulsar wind nebulae in starburst galaxies
High Energy Astrophysical Phenomena (astro-ph.HE)
2010/12/28
Recently, gamma ray emission at TeV energies has been detected from the starburst galaxies NGC253 [1] and M82 [2].
A Spitzer/IRS spectral study of a sample of galactic carbon-rich proto-planetary nebulae
Solar and Stellar Astrophysics (astro-ph.SR)
2010/12/27
Recent infrared spectroscopic observations have shown that proto-planetary nebulae (PPNs) are sites of active synthesis of organic compounds in the late stages of stellar evolution. This paper present...
Wolf-Rayet Central Stars of Planetary Nebulae: Their Evolution and Properties
Solar and Stellar Astrophysics (astro-ph.SR)
2010/12/24
Over the past decade, the number of planetary nebula central stars (CSPN) known to exhibit the Wolf-Rayet (WR) phenomenon has grown substantially. Many of these discoveries have resulted from the Macq...
The Physical Characteristics of Binary Central Stars of Planetary Nebulae
Solar and Stellar Astrophysics (astro-ph.SR)
2010/12/24
A number of efforts are underway to detect close binary stars in planetary nebulae. The primary goal of these studies is to determine the binary fraction of central stars.