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Preparation of Free-Surface Hyperbolic Water Vortices
Published on: July 28, 2023
Origin of the warped heliospheric current sheet
Science (New York, N.Y.)
|August 1, 1980
Summary
Researchers mapped the heliospheric current sheet using photospheric magnetic fields. The model accurately predicted interplanetary magnetic field polarity, confirming the photospheric field
Area of Science:
- Heliophysics
- Solar Physics
- Magnetohydrodynamics
Background:
- The heliospheric current sheet (HCS) separates regions of opposite magnetic polarity in the heliosphere.
- Understanding the HCS structure is crucial for space weather prediction and cosmic ray modulation.
Purpose of the Study:
- To calculate the warped heliospheric current sheet for early 1976.
- To compare the calculated HCS with observed interplanetary magnetic field (IMF) polarity.
Main Methods:
- Potential field method applied to observed photospheric magnetic field data.
- Comparison with in-situ IMF polarity measurements from Helios 1, Helios 2, Pioneer 11, and Earth.
Main Results:
- The computed warped heliospheric current sheet showed detailed agreement with observed IMF polarity.
- The large-scale HCS structure is primarily determined by the photospheric magnetic field structure.
Conclusions:
- The potential field method is effective in modeling the large-scale HCS.
- Photospheric magnetic field dictates the overall HCS shape, with smaller variations possibly due to "ballerina skirt" effects.
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