Spectropolarimetry of Supernovae
arXiv:0811.1054 · doi:10.1146/annurev.astro.46.060407.145139
Abstract
Overwhelming evidence has accumulated in recent years that supernova explosions are intrinsically 3-dimensional phenomena with significant departures from spherical symmetry. We review the evidence derived from spectropolarimetry that has established several key results: virtually all supernovae are significantly aspherical near maximum light; core-collapse supernovae behave differently than thermonuclear (Type Ia) supernovae; the asphericity of core-collapse supernovae is stronger in the inner layers showing that the explosion process itself is strongly aspherical; core-collapse supernovae tend to establish a preferred direction of asymmetry; the asphericity is stronger in the outer layers of thermonuclear supernovae providing constraints on the burning process. We emphasize the utility of the Q/U plane as a diagnostic tool and revisit SN 1987A and SN 1993J in a contemporary context. An axially-symmetric geometry can explain many basic features of core-collapse supernovae, but significant departures from axial symmetry are needed to explain most events. We introduce a spectropolarimetry type to classify the range of behavior observed in polarized supernovae. Understanding asymmetries in supernovae is important for phenomena as diverse as the origins of gamma-ray bursts and the cosmological applications of Type Ia supernovae in studies of the dark energy content of the universe.
Draft of Annual Review article prior to final copy editing; 85 pages, 13 figures, 1 table
References in corpus (5)
- The Supernova -- Gamma-Ray Burst Connection
- The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode as Deflagrations?
- Detonating Failed Deflagration Model of Thermonuclear Supernovae I. Explosion Dynamics
- Detection of optical linear polarization in the SN2006aj/XRF060218 non-spherical expansion
- Moderate Asphericity of the SN 2002ic Circumstellar Envelope