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تسجيل مستخدم جديدProperties of newly formed dust by SN2006jc based on near-to-mid infrared observation with AKARI
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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 $6.9pm 0.5 times 10^{-5}M_{odot}$ 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.
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