The Bulletin of The Korean Astronomical Society (천문학회보)
- Volume 38 Issue 1
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- Pages.49.1-49.1
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- 2013
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- 1226-2692(pISSN)
Near-infrared studies of iron knots in Cassiopeia A supernova remnant: I. Spectral classification using principal component analysis
- Lee, Yong-Hyun (Department of Physics and Astronomy, Seoul National University) ;
- Koo, Bon-Chul (Department of Physics and Astronomy, Seoul National University) ;
- Moon, Dae-Sik (Department of Astronomy & Astrophysics, University of Toronto) ;
- Burton, Michael G. (School of Physics, University of New South Wales)
- Published : 2013.04.11
Abstract
We have been carrying out near-infrared (NIR) spectroscopy as well as [Fe II] narrow band imaging observations of Cassiopeia A supernova remnant (SNR). In this presentation, we describe the spectral classification of the iron knots around the SNR. From eight long-slit spectroscopic observations for the iron-bright shell, we identified a total of 61 iron knots making use of a clump-finding algorithm, and performed principal component analysis in an attempt to spectrally classify the iron knots. Three major components have emerged from the analysis; (1) Iron-rich, (2) Helium-rich, and (3) Sulfur-rich groups. The Helium-rich knots have low radial velocities (
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