Polarization and the Evolution of Expansion Velocity in Type Ia Supernovae
Abstract
Spectropolarimetric observations of Type Ia supernovae (SNIa) have been increasing in an effort to explore the asymmetric outermost ejecta of these explosive objects. Low continuum polarization measurements with slightly higher detections across certain spectral lines point to approximately spherical photospheres with chemical enrichments in the overlying layers. As each SN’s photosphere recedes through this clumpy ejecta, a spectral line displays a unique velocity gradient in time. Previous studies suggest a SNIa’s velocity gradient is well-correlated to the polarization of the Si II 6355Å line. However the gradient is derived at a time when the polarization of the SN is declining or at a minimum. We investigate the relationship between the expansion velocity’s temporal evolution and the polarization of specific features at similar epochs of observations to determine the impact on this correlation.
- Publication:
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American Astronomical Society Meeting Abstracts
- Pub Date:
- June 2013
- Bibcode:
- 2013AAS...22211807P