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Published on: December 14, 2017
Spectropolarimetric diagnostics of thermonuclear supernova explosions
Lifan Wang1, Dietrich Baade, Ferdinando Patat
1Physics Department, Texas A&M University, College Station, TX 77843-4242, USA. wang@physics.tamu.edu
Science (New York, N.Y.)
|December 2, 2006
Summary
Spectropolarimetry reveals that type Ia supernova ejecta have a smooth, iron-rich core and asymmetric outer layers. This asymmetry correlates with light-curve decline rates, supporting delayed-detonation models.
Area of Science:
- * Astrophysics and cosmology
- * Stellar evolution and nucleosynthesis
Background:
- * Spectropolarimetry is a powerful tool for diagnosing supernova ejecta geometry at extragalactic distances.
- * Previous studies have hinted at geometric variations in Type Ia supernovae, but lacked statistical power.
Purpose of the Study:
- * To statistically investigate the correlation between geometric structures and observable parameters of Type Ia supernovae.
- * To constrain theoretical models of Type Ia supernova explosions.
Main Methods:
- * Spectropolarimetric observations of 17 Type Ia supernovae.
- * Analysis of correlations between ejecta geometry and light-curve properties.
Main Results:
- * Type Ia supernova ejecta typically exhibit a smooth, central, iron-rich core.
- * An outer layer with chemical asymmetries is commonly observed.
- * The degree of peripheral asphericity correlates with the light-curve decline rate.
Conclusions:
- * The observed ejecta structures provide strong support for delayed-detonation models of Type Ia supernovae.
- * Chemical and geometric asymmetries are key features of Type Ia supernova explosions.
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