352 citations · 1.6k across the 43 of their papers we have counts for
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The Evolution of NGC 7027 at Radio Frequencies: A New Determination of the Distance and Core Mass
Albert Zijlstra, P. A. M. van Hoof, R. A. Perley
We present the results of a 25-year program to monitor the radio flux evolution of the planetary nebula NGC7027. We find significant evolution of the spectral flux densities. The f…
A PDR-Code Comparison Study
M. Roellig, N. P. Abel, T. Bell +21
We present a comparison between independent computer codes, modeling the physics and chemistry of interstellar photon dominated regions (PDRs). Our goal was to understand the mutua…
Introducing EMILI: Computer Aided Emission Line Identification
Brian Sharpee, Robert Williams, Jack A. Baldwin +1
The identification of spectral lines can be a tedious process requiring the interrogation of large spectroscopic databases, but it does lend itself to software algorithms that can…
Properties of post-AGB stars with IRAS colors typical of planetary nebulae
Griet C. Van de Steene, Peter A. M. van Hoof, Peter R. Wood
We have investigated the infrared properties of a sample of objects with IRAS colors typical of planetary nebulae. The selected objects have not yet evolved to the planetary nebula…
Measuring angular diameters of extended sources
P. A. M. van Hoof
When measuring diameters of partially resolved sources often a technique called gaussian deconvolution is used. This technique yields a gaussian diameter which subsequently has to…
Properties of Dust Grains in Planetary Nebulae -- I. The Ionized Region of NGC 6445
P. A. M. van Hoof, G. C. Van de Steene, D. A. Beintema +3
In this paper we study new infrared spectra of the evolved planetary nebula NGC 6445 obtained with ISO. These data show that the thermal emission from the grains is very cool and h…