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Colliding White Dwarfs

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Contact: F.X.Timmes
my one page vitae,
full vitae,
research statement, and
teaching statement.
Collisions III (2012)
In this paper by Hawley et al we examine head-on collisions between two white dwarfs as potential supernova type Ia candidates using an adative mesh grid tool (FLASH). Even the highest resolution models do not quite achieve strict numerical convergence, due to the challenge of properly resolving small-scale burning and energy transport. The lack of strict numerical convergence from these idealized configurations suggests that quantitative predictions of the ejected elemental abundances that are generated by binary white dwarf collision and merger simulations should be viewed with caution.

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head-on collision
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abundance and energy convergence trends
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timestep evolution


Collisions II (2010)
In this paper by Raskin et al we systematically explore collisions between two white dwarfs as potential supernova type Ia candidates using the smooth particle software instrument SNSPH. We find collisions can produce enough 5656, silicon and unburned carbon to span the entire range of observed luminosities, from the overluminal (super Chandrasekhar) to the subluminal, depending on the mass pairs and impact parameter.

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head-on collision
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45 degree collision
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Grazing collision
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0.6 x 0.6 dashboard movie
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0.6 x 0.8 dashboard movie
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0.6 x 1.0 dashboard movie


Collisions I (2009)
In this letter by Raskiin et al we explore collisions between two white dwarfs as a pathway for either a new class of transients or white dwarf supernovae using a smooth particle hydrodynamics software instrument (SNSPH).

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head-on collision
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the shock stalls
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convergence of yields