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Author Spotlight: Non-Invasive Imaging of Complex Bio-Structures Using Polarization-Sensitive Two-Photon Microscopy
Published on: September 8, 2023
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Polarized thermal emission from dust in a galaxy at redshift 2.6
J E Geach1, E Lopez-Rodriguez2, M J Doherty3
1Centre for Astrophysics Research, School of Physics, Engineering and Computer Science, University of Hertfordshire, Hatfield, UK. j.geach@herts.ac.uk.
Nature
|September 6, 2023
Summary
Early galaxies rapidly formed ordered magnetic fields, crucial for star formation. Observations reveal a 5-kiloparsec-scale magnetic field in a distant galaxy, showing these structures develop quickly in cosmic history.
Area of Science:
- Astrophysics
- Cosmic Evolution
- Galactic Dynamics
Background:
- Magnetic fields are essential for galaxy evolution, interstellar medium, and star formation.
- Large-scale magnetic fields are known in nearby galaxies, but their early universe formation is unclear.
Purpose of the Study:
- To investigate the formation and structure of magnetic fields in the early universe.
- To determine if ordered magnetic fields form rapidly in galaxies.
Main Methods:
- Detection of linearly polarized thermal emission from dust grains.
- Observation of a strongly lensed, luminous galaxy at redshift 2.6.
- Analysis of dust grain alignment with the local magnetic field.
Main Results:
- Detection of a 5-kiloparsec-scale ordered magnetic field.
- Magnetic field strength estimated at approximately 500 μG or lower.
- Polarization fraction of ~1%, similar to nearby spiral galaxies.
- Magnetic field oriented parallel to the molecular gas disk.
Conclusions:
- Ordered magnetic fields can form rapidly in galaxies.
- These structures were present early in cosmic history.
- Findings support the role of magnetic fields in early galaxy evolution and star formation.
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