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Updated: Jul 29, 2026
11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
Pulsar recoil by large-scale anisotropies in supernova explosions
L Scheck1, T Plewa, H-Th Janka
1Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Strasse 1, D-85741 Garching, Germany.
Physical Review Letters
|February 3, 2004
Summary
Supernova explosions driven by neutrino heating can cause convection, leading to asymmetric ejecta. This asymmetry accelerates neutron stars to high velocities, matching observed pulsar motions.
Area of Science:
- Astrophysics
- Nuclear Physics
- Computational Physics
Background:
- Neutrino-driven supernova explosions are a key mechanism for heavy element nucleosynthesis.
- The role of convection in supernova dynamics and neutron star kicks remains an active area of research.
Purpose of the Study:
- To investigate the development of convection in supernova explosions driven by neutrino heating.
- To determine if convection can explain the observed high velocities of neutron stars (pulsar proper motions).
Main Methods:
- Numerical simulations of supernova explosions incorporating neutrino-heating and convection.
- Analysis of the impact of slow versus burstlike core luminosity on explosion dynamics.
Main Results:
- Low-mode (l=1,2) convection develops behind the shock if neutrino luminosity is high and varies slowly.
- Asymmetric ejecta from convection generate gravitational and hydrodynamic forces.
- These forces accelerate the remnant neutron star to velocities exceeding 500 km/s.
Conclusions:
- A slow onset of supernova explosions is crucial for developing convection and asymmetric ejecta.
- The model successfully explains the high velocities of neutron stars, consistent with pulsar proper motion observations.
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