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Asymmetric Explosion of Type Ia Supernovae as Seen from Near Infrared Observations

K. Motohara·K. Maeda·C. L. Gerardy·K. Nomoto·M. Tanaka·N. Tominaga·T. Ohkubo·P. A. Mazzali·R. A. Fesen·P. Hoeflich·J. C. Wheeler
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Abstract

We present near-infrared spectra of late phase (>200 d) Type Ia supernovae (SNe Ia) taken at the Subaru telescope. The [Fe II] line of SN 2003hv shows a clear flat-topped feature, while that of SN 2005W show less prominent flatness. In addition, a large shift in their line center, varying from -3000 to 1000 (km/s) with respect to the host galaxies, is seen. Such a shift suggests the occurrence of an off-center, non-spherical explosion in the central region, and provides important, new constraints on the explosion models of SNe Ia.

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K. Motohara, K. Maeda, C. L. Gerardy, K. Nomoto, M. Tanaka, N. Tominaga, T. Ohkubo, P. A. Mazzali, R. A. Fesen, P. Hoeflich, J. C. Wheeler. 2006-11-24. Asymmetric Explosion of Type Ia Supernovae as Seen from Near Infrared Observations. https://doi.org/10.1086/509919

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