# A SPITZER STUDY OF 21 AND 30 μm EMISSION IN SEVERAL GALACTIC CARBON-RICH PROTOPLANETARY NEBULAE

@article{Hrivnak2009ASS,
title={A SPITZER STUDY OF 21 AND 30 $\mu$m EMISSION IN SEVERAL GALACTIC CARBON-RICH PROTOPLANETARY NEBULAE},
author={Bruce J. Hrivnak and Kevin M. Volk and Sun Kwok},
journal={The Astrophysical Journal},
year={2009},
volume={694},
pages={1147-1160}
}
• Published 31 January 2009
• Physics
• The Astrophysical Journal
We have carried out mid-infrared spectroscopy of seven Galactic protoplanetary nebulae (PPNs) using the Spitzer Space Telescope. They were observed from 10 to 36 μm at relatively high spectral resolution, R ≈ 600. The sample was chosen because they all gave some evidence in the visible of a carbon-rich chemistry. All seven of the sources show the broad, unidentified 21 μm emission feature; three of them are new detections (IRAS 06530 – 0213, 07430+1115, and 19477+2401) and the others are…

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