SASI Rotation
SASI in a Spinning Star
-
Blondin, J. M., Mezzacappa, A., & DeMarino, C. 2003, ApJ, 584, 971
Stability of Standing Accretion Shocks, With an Eye Toward Core Collapse Supernovae
- Original discovery of the SASI. Attributed instability to Vortical Acoustic coupling
described by Foglizzo, but is not (?) the case.
-
Blondin, J. M. & Shaw, S. 2007, ApJ, 656, 366
Linear Growth of Spiral SASI Modes in Core-Collapse Supernovae
- Two-dimensional simulations in the equatorial plane are used to study non-axisymmetric modes of the SASI.
These modes are excited by dropping a density perturbation onto the accretion shock. The perturbation is in
the shape of a bar oriented at an angle with respect to the spherical shock. The result sends a wave rotating
around the accreting star. The amplitude of the perturbation is tracked by computing the Fourier components
of the angular velocity.
-
Blondin, J. M. & Mezzacappa, A. 2007, Nature, 445, 58
Pulsar Spins from an Instability in the Accretion Shock of Supernovae
-
-
Yamasaki, T. & Foglizzo, T. 2008, ApJ, 679, 607
Effect of Rotation on the Stability of a Stalled Cylindrical Shock and Its Consequences for Core-Collapse Supernovae
-
-
Laming, J. M. 2007, ApJ, 659, 1449
Analytic Approach to the Stability of Standing Accretion Shocks: Application to Core-Collapse Supernovae
- This author used an approximate analytic method (following Vishniac & Ryu 1989) to find a dispersion
relation for the modes of a spherical accretion shock. He found growing oscillations for low-order
sloshing modes (l=1,2), in agreement with numerical simulations. For ratios of the shock radius to
stellar radius appropriate to supernovae, he found the instability existed even when the advection terms
were removed from the equations - hence the SASI is NOT dependent on advection and is NOT related to the
Vortical Acoustic instability as originally proposed. He argues that growth rates will be higher
with increasing rotation for m=1.
Last update May 22, 2008
Research by
John M. Blondin
Department of Physics,
North Carolina State University