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arXiv · 2211.11021

Unidentified infrared bands do not correlate with C/O ratio in planetary nebulae

Frederic Zagury
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Abstract

The concrete evidence adduced to support the widely held idea that unidentified infrared bands (UIBs) are enhanced in carbon-rich planetary nebulae (PNe) is a remarkable UIB 7.7 {\mu}m versus C/O ratio correlation plot for six PNe, obtained from air-born observations and published in 1986 by M. Cohen and coworkers. However, the space-born data presented by Cohen & Barlow in 2005 undercut this correlation, and I show that the larger dataset they provide disproves a specific link between UIBs and carbon abundance in PNe. It also follows from these data that interstellar UIB carriers cannot originate from the atmosphere of carbon-rich PNe.

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Frederic Zagury. 2022-11-20. Unidentified infrared bands do not correlate with C/O ratio in planetary nebulae. https://arxiv.org/abs/2211.11021

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