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Rapid Repetition Rate Fluctuation Measurement of Soliton Crystals in a Microresonator
Published on: December 15, 2021
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Sub-second periodicity in a fast radio burst
, Bridget C Andersen1,2, Kevin Bandura3,4
1Department of Physics, McGill University, Montréal, Québec, Canada.
Nature
|July 13, 2022
Summary
Researchers detected a repeating Fast Radio Burst (FRB) with a unique periodic signal. This discovery provides strong evidence for a neutron-star origin and magnetospheric emission for these mysterious cosmic events.
Area of Science:
- Astronomy and Astrophysics
- Cosmic Transients
- Radio Astronomy
Background:
- Fast Radio Bursts (FRBs) are enigmatic, millisecond-duration radio flashes originating from extragalactic distances.
- The progenitors and emission mechanisms of FRBs remain significant open questions in astrophysics.
- Previous FRB detections have not conclusively identified their origins or emission processes.
Purpose of the Study:
- To investigate the nature of Fast Radio Burst progenitors and their emission mechanisms.
- To analyze the properties of the peculiar multicomponent FRB 20191221A.
- To determine if periodic behavior can be identified in FRB signals.
Main Methods:
- Detection and analysis of the multicomponent Fast Radio Burst 20191221A.
- Identification of periodic separation between the burst components using signal processing techniques.
- Statistical analysis to determine the significance of the observed periodicity.
Main Results:
- Detection of FRB 20191221A, an outlier FRB with a long duration (approx. 3 s) and at least nine components.
- Identification of a significant periodic separation of 216.8(1) ms between the burst components (6.5σ significance).
- The observed periodicity strongly suggests a neutron-star origin for the FRB event.
Conclusions:
- The short periodicity observed in FRB 20191221A provides compelling evidence for a neutron-star progenitor.
- The findings favor emission models originating from the neutron-star magnetosphere.
- This study advances our understanding of FRB origins and emission physics.
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