Magnetic fields & electron flow in galaxies

[Weltevreden SA (Dana)]

Hi all, magnetic fields propagate at right angles to the direction of electron flow. i.e., in a "tube" running parallel to an electric current. Many spirals have magnetic fields that roughly follow the directional rotation of the arms. In which way do the electrons flow? If at a right angle, do they move toward the centre or outer reaches of the arm, or do they stream outward from the galaxy into the intergalactic medium? Clearly they won't go far because the disk-following magnetic fields weaken rapidly above or below the galactic plane. Does anyone know or have a link to electron propagation in galaxies?

[LAW (Murphy)]

Oo gan dit Dana? (Sorry about the spelling, I'm pretty sure that's wrong).

My guess would be that there is no massive overriding magnetic field in a galaxy. Just like a glass of water is made of water molecules, each with a huge magnetic dipole, the glass doesn't affect compasses (neither does the ocean). While the magfields are strong, there are equal(ish) numbers of them in equal(ish) directions to roughly cancel out.

[LAW (Murphy)]

The 'mutually perpendicular' principle (I think) really only applied in a system of interactions. For example in an electric motor the charge creates a field, which makes motion. The flow of charge, field and motion are all 90 degrees from each other. But for electrons in a galaxy their flow of charge isn't being generated by motion through any single field so their motion would be scattered.

I think because each separate heliosphere would have a different field orientation and strength as well as relative motion to neighboring heliospheres it would be far too random to calculate and probably have a net zero value.

But I'm not sure and I haven't researched it. If you do find out, or if anyone knows the answer I'd be fascinated to find out.

[Scorpius51 (John)]

Originally Posted by Weltevreden SA

Hi all, magnetic fields propagate at right angles to the direction of electron flow. i.e., in a "tube" running parallel to an electric current. Many spirals have magnetic fields that roughly follow the directional rotation of the arms. In which way do the electrons flow? If at a right angle, do they move toward the centre or outer reaches of the arm, or do they stream outward from the galaxy into the intergalactic medium? Clearly they won't go far because the disk-following magnetic fields weaken rapidly above or below the galactic plane. Does anyone know or have a link to electron propagation in galaxies?

This may be of some interest http://www3.mpifr-bonn.mpg.de/div/me...k_Galaxies.pdf

Cheers
John