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Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
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Repeating fast radio burst 20201124A originates from a magnetar/Be star binary
F Y Wang1,2, G Q Zhang3, Z G Dai3,4
1School of Astronomy and Space Science, Nanjing University, Nanjing, 210093, China. fayinwang@nju.edu.cn.
Nature Communications
|September 21, 2022
Summary
Fast radio bursts (FRBs) may originate from magnetar-Be star binaries. Radio wave propagation through a Be star
Area of Science:
- Astrophysics
- Cosmic phenomena
Background:
- Fast radio bursts (FRBs) are enigmatic millisecond-duration cosmic radio emissions.
- The physical origins and central engines of FRBs remain largely unknown.
- Variations in Faraday rotation and dispersion measures offer critical insights into FRB environments.
Purpose of the Study:
- To explain the observed characteristics of FRB 20201124A.
- To propose a physical model for repeating FRB signals.
Main Methods:
- Development of a physical model for FRB 20201124A.
- Analysis of rotation measure variations on a daily timescale.
- Modeling radio wave propagation through a decretion disk.
Main Results:
- The model successfully explains the observed varying rotation measure, depolarization, scattering timescale, and Faraday conversion for FRB 20201124A.
- The observed rotation measure oscillations suggest magnetic field reversals along the line of sight.
- The model indicates that repeating FRB signals can arise from binary systems.
Conclusions:
- A binary system comprising a magnetar and a Be star with a decretion disk is proposed as the source of repeating FRBs.
- Magnetar proximity to periastron within the Be star's disk naturally produces observed radio signal variations.
- This study encourages targeted searches for FRB signals from Be/X-ray binary systems.
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