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Updated: Aug 13, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Unveiling dominant toroidal magnetic fields in a protostellar outflow
T-C Ching1,2, Z-Y Li3, Q Zhang4
1National Radio Astronomy Observatory, 1011 Lopezville Road, Socorro, NM, USA. tching@nrao.edu.
Nature Communications
|August 11, 2026
Summary
Toroidal magnetic fields, crucial for protostellar winds, were observed for the first time. These fields, detected via carbon monoxide emission, collimate and accelerate outflows, supporting the magneto-centrifugal wind model.
Area of Science:
- Astrophysics
- Magnetohydrodynamics
Background:
- Protostellar winds are essential for star formation.
- Magneto-centrifugal models propose magnetic fields launch and shape these winds.
- Observational evidence for toroidal magnetic fields in protostellar outflows is lacking.
Purpose of the Study:
- To observationally resolve toroidal magnetic fields in protostellar outflows.
- To investigate the role of magnetic fields in collimating and accelerating protostellar winds.
- To test predictions of the magneto-centrifugal wind model.
Main Methods:
- Polarization observations of carbon monoxide (CO) emission.
- Analysis of NGC1333 IRAS 4A protostellar outflow.
- Magnetic field inference and correlation analysis.
Main Results:
- Inferred magnetic fields are toroidal, perpendicular to the outflow axis.
- Toroidal field strengths are a few milligauss, sufficient for collimation and acceleration.
- A linear correlation between magnetic field curl and electric current density was found.
Conclusions:
- The findings provide direct evidence for toroidal magnetic fields in protostellar outflows.
- The results support the magneto-centrifugal mechanism as the driver of rotating protostellar outflows.
- Constraints on ion-electron drift velocity in outflows are improved.
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