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Updated: Jul 25, 2026
08:32
External Excitation of Neurons Using Electric and Magnetic Fields in One- and Two-dimensional Cultures
Published on: May 7, 2017
A periodically active pulsar giving insight into magnetospheric physics
M Kramer1, A G Lyne, J T O'Brien
1Jodrell Bank Observatory, University of Manchester, Macclesfield, SK11 9DL, UK.
Science (New York, N.Y.)
|February 25, 2006
Summary
PSR B1931+24, a radio pulsar, exhibits unique on/off cycles. Its spin-down rate increases significantly when active, revealing insights into pulsar wind and magnetospheric currents.
Area of Science:
- Astronomy
- Astrophysics
- Pulsar Physics
Background:
- PSR B1931+24 (J1933+2421) is an isolated radio pulsar.
- Pulsars are known for their rotational properties and emission characteristics.
Purpose of the Study:
- To investigate the unusual on/off behavior of PSR B1931+24.
- To understand the role of pulsar wind in the pulsar's spin-down.
- To estimate magnetospheric currents in a pulsar.
Main Methods:
- Observational astronomy focusing on radio emission and pulsar rotation.
- Analysis of pulsar spin-down rates during active and inactive phases.
Main Results:
- PSR B1931+24 displays quasi-periodic on/off states, with radio emission switching off in seconds and remaining undetectable for weeks.
- The pulsar's rotation slows down 50% faster during active radio emission phases.
- A significant increase in magnetospheric currents is observed when the pulsar switches on.
Conclusions:
- Pulsar wind plays a substantial role in the spin-down of PSR B1931+24.
- This study provides the first estimation of magnetospheric currents during radio emission in a pulsar.
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