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Diverse polarization angle swings from a repeating fast radio burst source
R Luo1,2,3, B J Wang1,2, Y P Men1,2
1Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing, China.
Nature
|October 29, 2020
Summary
Observations of Fast Radio Bursts (FRBs) reveal diverse polarization angle swings. These findings support magnetospheric origins for FRB emission, challenging shock-based radiation models.
Area of Science:
- Astrophysics
- Radio Astronomy
Background:
- Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown origin.
- Current theories suggest emission mechanisms involving neutron star magnetospheres or relativistic shocks.
- Polarization observations are crucial for understanding FRB emission but have yielded perplexing data.
Purpose of the Study:
- To investigate the emission mechanism of Fast Radio Bursts (FRBs) through detailed polarization observations.
- To analyze the polarization properties of multiple bursts from a single FRB source (FRB 180301).
Main Methods:
- Observed 15 bursts from the FRB 180301 source.
- Analyzed the polarization angle variations within these bursts.
Main Results:
- Observed various polarization angle swings in seven out of the 15 analyzed bursts.
- The diversity of polarization features was noted across the observed bursts.
Conclusions:
- The diverse polarization angle swings observed in FRB 180301 are consistent with a magnetospheric origin for the radio emission.
- These findings disfavor radiation models that invoke relativistic shocks as the primary emission mechanism for FRBs.
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