13 papers
Sh2-188: a model for a speedy PN
C. J. Wareing, T. J. O'Brien, A. A. Zijlstra +1
Sh2-188 is thought to be an ancient planetary nebula in the galactic disk. It appears to be one-sided with recent observations revealing structure behind the filamentary limb. We p…
Late stages of stellar evolution with the Square Kilometer Array
Albert Zijlstra
Stars at the end of their lives return much of their mass back to the ISM. This process is the main source of dust in the ISM, and potentially a source of large molecules. I discus…
Hydrogen-poor planetary nebulae
Albert A. Zijlstra
Five planetary nebulae are known to show hydrogen-poor material near the central star. In the case of A58, this gas was ejected following a late thermal pulse similar to Sakurai's…
A radio-continuum and photoionization-model study of the two planetary nebulae in the Sagittarius dwarf galaxy
G. Dudziak, D. Pequignot, A. A. Zijlstra +1
Radio continuum observations at 1.4, 4.8 and 8.6 GHz of the two Planetary Nebulae (PNe) in the Sagittarius dwarf galaxy reveal the elongated shape of Wray 16-423 and the extreme co…
Third-dredge-up oxygen in planetary nebulae
D. Pequignot, J. R. Walsh, A. A. Zijlstra +1
The planetary nebulae He 2-436 and Wray 16-423 in the Sagittarius dwarf galaxy appear to result from nearly twin stars, except that third-dredge-up carbon is more abundant in He 2-…
Mass-loss rates and luminosity functions of dust-enshrouded AGB stars and red supergiants in the LMC
Jacco Th. van Loon, M. A. T. Groenewegen, A. de Koter +5
A radiative transfer code is used to model the spectral energy distributions of 57 mass-losing Asymptotic Giant Branch (AGB) stars and red supergiants (RSGs) in the Large Magellani…