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arXiv · 2210.15708

Superposing the Magnetic spiral structure of the Milky Way, on the stellar spiral arms -- Matching the unique galactic magnetic field reversal Zone with two galactic spiral arm Segments

Jacques P Vallee
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Abstract

To pinpoint the peak location of the synchrotron total intensity emission in a spiral arm, we use a map of the spiralarm locations (from the observed arm tangent). Thus In a typical spiral arm in Galactic Quadrant I, we find the peak of the synchrotron radiation to be located about 220 +/-40 pc away from the inner arm edge (hot dust lane) inside the spiral arm. While most of the galactic disk has a clockwise largescale magnetic field, we make a statistical analysis to delimitate more precisely the smaller reverse annulus wiith a counterclockwise galactic magnetic field. We find an annulus width of 2.1 +/-0.3 kpc (measured along the Galactic radius), located from 5.5 to 7.6 kpc from the Galactic Center). The annulus does not overlay with a single spiral arm -- it encompasses segments of two different spiral arms. Using a recent delineation of the position of spiral arms, the field-reversed annulus is seen to encompass the Crux-Centaurus arm (in Galactic Quadrant IV) and the Sagittarius arm (in Galactic Quadrant I).

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Jacques P Vallee. 2022-10-27. Superposing the Magnetic spiral structure of the Milky Way, on the stellar spiral arms -- Matching the unique galactic magnetic field reversal Zone with two galactic spiral arm Segments. https://doi.org/10.4236/ijaa.2022.124017

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