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Can a large neutron excess help solve the baryon loading problem in gamma-Ray burst fireballs?
1Department of Physics, University of California, San Diego, La Jolla, California 92093-0319, USA.
Physical Review Letters
|September 16, 2000
Summary
Converting baryons to neutrons can solve the baryon loading problem in gamma-ray bursts (GRBs). This neutron conversion reduces energy transfer, lowering the energy needed for relativistic flow in GRBs.
Area of Science:
- Astrophysics
- High-energy astrophysics
- Nuclear astrophysics
Background:
- The baryon loading problem poses a significant challenge in current gamma-ray burst (GRB) models.
- This problem concerns the difficulty in explaining the low baryon content observed in GRB fireballs.
Purpose of the Study:
- To propose a mechanism for ameliorating the baryon loading problem in GRB models.
- To investigate the role of neutron conversion in reducing energy requirements for GRB outflows.
Main Methods:
- Theoretical modeling of fireball dynamics.
- Analysis of particle energy transfer in relativistic outflows.
- Investigating neutron-to-proton ratios in astrophysical environments.
Main Results:
- A high neutron fraction can significantly reduce energy transfer from relativistic particles to baryons.
- The energy required to produce relativistic flow in GRBs can be reduced by orders of magnitude.
- High neutron-to-proton ratios are plausible in neutron star-merger and compact object environments.
Conclusions:
- Neutron conversion offers a viable solution to the baryon loading problem in GRBs.
- Astrophysical environments with high neutrino fluxes or neutron star mergers can facilitate the necessary neutron excess.
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