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The nature of near-infrared emission from spiral galaxies

P. A. James·M. S. Seigar
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Abstract

We present K-band spectroscopy for several regions of three nearby spiral galaxies, NGC 613, NGC 628 and NGC 7741. Analysis of the depth of the 2.293 micron CO absorption feature in these spectra reveals that some regions have deep absorptions, indicative of recent star formation, while others have anomalously shallow absorptions. We interpret the latter as evidence for a significant but localised contribution to the 2.3 micron light from hot dust with an effective temperature of about 1000 K, which could have a significant effect on the K-band morphologies of star-forming galaxies.

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P. A. James, M. S. Seigar. 1999-09-13. The nature of near-infrared emission from spiral galaxies. https://arxiv.org/abs/astro-ph/9909200

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