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Massive-Star Supernovae as Major Dust Factories
Observations of the Type II supernova 2003gd show that dust formation in supernova ejecta can be efficient and that massive-star supernovae could have been major dust producers throughout the history of the universe.
Dust features in the 10-mu m infrared spectra of oxygen-rich evolved stars
We have analyzed the 8 13:5 mU KIRT CGS3 spectra of 142 M-type stars including 80 oxygen- rich AGB stars and 62 red supergiants, with a view to understanding the dierences and similarities between
We present a deep and wide field-of-view (4' x 7') image of the planetary nebula (PN) NGC 7293 (the Helix Nebula) in the 2.12 {mu}m H{sub 2} v = 1 {yields} 0 S(1) line. The excellent seeing (0.''4)
Silicon Carbide Absorption Features: Dust Formation in the Outflows of Extreme Carbon Stars
Infrared carbon stars without visible counterparts are generally known as extreme carbon stars. We have selected a subset of these stars with absorption features in the 10-13 μm range, which has been
Large-Scale Extended Emission around the Helix Nebula: Dust, Molecules, Atoms, and Ions
We present new observations of the ionized gas, molecular gas, and cool dust in the Helix Nebula (NGC 7293). The ionized gas is observed in the form of an Himage, which is constructed using images
The Effect of Stellar Evolution on SiC Dust Grain Sizes
Stars on the asymptotic giant branch (AGB) produce dust in their circumstellar shells. The nature of the dust-forming environment is influenced by the evolution of the stars, in terms of both
An Introduction to the Physics of Interstellar Dust
The Dielectric Permeability How the electromagnetic field acts on dust The harmonic oscillator Waves in a conducting medium How to Evaluate Grain Cross Sections Defining cross sections The optical
The Multitude of Molecular Hydrogen Knots in the Helix Nebula
We present Hubble Space Telescope NICMOS imaging of the H2 2.12 μm emission in five fields in the Helix Nebula ranging in radial distance from 250'' to 450'' from the central star. The images reveal
Processing of Presolar Grains around Post-Asymptotic Giant Branch Stars: Silicon Carbide as the Carrier of the 21 Micron Feature
Some proto–planetary nebulae (PPNs) exhibit an enigmatic feature in their infrared spectra at � 21 m. This feature is not seen in the spectra of either the precursors to PPNs, the asymptotic giant