Properties of newly formed dust by SN2006jc based on near-to-mid infrared observation with AKARI

TL;DR

This study analyzes near- to mid-infrared observations of SN2006jc, revealing the formation of amorphous carbon dust in the supernova ejecta and pre-existing dust in the stellar wind, with implications for dust production in supernovae.

Contribution

First infrared spectrum of SN2006jc obtained, identifying newly formed and pre-existing amorphous carbon dust, providing insights into dust formation processes in supernovae.

Findings

Detected 800K amorphous carbon dust in ejecta with mass ~7x10^-5 M_sun

Identified warm 320K amorphous carbon dust with mass ~2.7x10^-3 M_sun in circumstellar wind

Suggested possible SiO molecular emission features in mid-infrared spectrum

Abstract

We present our latest results on near- to mid- infrared observation of SN2006jc at 200 days after the discovery using the Infrared Camera (IRC) on board $AKARI$. The near-infrared (2--5$\mu$m) spectrum of SN2006jc is obtained for the first time and is found to be well interpreted in terms of the thermal emission from amorphous carbon of 800$\pm 10$K with the mass of $6.9\pm 0.5 \times 10^{-5}M_{\odot}$ that was formed in the supernova ejecta. This dust mass newly formed in the ejecta of SN 2006jc is in a range similar to those obtained for other several dust forming core collapse supernovae based on recent observations (i.e., $10^{-3}$--$10^{-5}$$M_{\odot}$). Mid-infrared photometric data with {\it{AKARI}}/IRC MIR-S/S7, S9W, and S11 bands have shown excess emission over the thermal emission by hot amorphous carbon of 800K. This mid-infrared excess emission is likely to be accounted for by the emission from warm amorphous carbon dust of 320$\pm 10$K with the mass of 2.7$^{+0.7}_{-0.5} \times 10^{-3}M_{\odot}$ rather than by the band emission of astronomical silicate and/or silica grains. This warm amorphous carbon dust is expected to have been formed in the mass loss wind associated with the Wolf-Rayet stellar activity before the SN explosion. Our result suggests that a significant amount of dust is condensed in the mass loss wind prior to the SN explosion. A possible contribution of emission bands by precursory SiO molecules in 7.5--9.5$\mu$m is also suggested.