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Updated: Jun 17, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Ten per cent polarized optical emission from GRB 090102
I A Steele1, C G Mundell, R J Smith
1Astrophysics Research Institute, Liverpool John Moores University, CH41 1LD, UK. ias@astro.livjm.ac.uk
Nature
|December 17, 2009
Summary
Early optical emission from gamma-ray bursts (GRBs) shows 10% polarization. This indicates large-scale magnetic fields originating from the expanding fireball, clarifying GRB jet composition.
Area of Science:
- Astrophysics
- High-energy astrophysics
Background:
- The composition and magnetic field structure of gamma-ray burst (GRB) jets are not well understood.
- Two models exist: baryon-dominated jets with weak, tangled fields, or jets with large-scale magnetic fields from the central engine.
Purpose of the Study:
- To investigate the role of magnetic fields in GRB jets by measuring early-time emission polarization.
- To differentiate between GRB jet models based on polarization characteristics.
Main Methods:
- Measured the polarization of early optical emission from GRB 090102.
- Utilized a 60-second exposure time for the observation.
Main Results:
- Detected 10 +/- 1 per cent polarization in the early optical emission of GRB 090102.
- The results suggest the presence of large-scale magnetic fields originating within the expanding fireball.
Conclusions:
- The findings support models where GRB jets are threaded with large-scale magnetic fields.
- Early optical polarization measurements are crucial for understanding GRB jet physics and magnetic field origins.
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