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Updated: Aug 10, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Summary
Simulations show relativistic jets from collapsar models remain collimated and accelerate after exiting massive stars. This research explores jet propagation through stellar interiors and into the surrounding medium.
Area of Science:
- Astrophysics
- Computational Physics
Background:
- Massive stars are crucial for cosmic evolution.
- Collapsar models explain energetic astrophysical phenomena.
Purpose of the Study:
- To simulate relativistic jet propagation from a collapsar progenitor.
- To analyze jet behavior within a massive star and in the circumstellar medium.
Main Methods:
- Utilized the GENESIS multidimensional relativistic hydrodynamic code.
- Employed a collapsar progenitor model (MacFadyen & Woosley).
- Simulated axisymmetric jet energy deposition (10^50-10^51 ergs s^-1).
Main Results:
- The relativistic jet remained intact and collimated upon reaching the stellar surface.
- The jet's maximum Lorentz factor was 33 at breakout.
- Post-breakout, the jet accelerated to a Lorentz factor of 44, maintaining collimation.
Conclusions:
- Relativistic jets from collapsars can successfully propagate through massive stars.
- Jet collimation is maintained even after exiting the star into the lower-density circumstellar medium.
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