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wolram
Apr4-05, 12:36 PM
Can anyone point me to some reference as to how magnetic fields are
produced in the inter stella medium please.

SpaceTiger
Apr4-05, 01:02 PM
I don't know much about the subject myself, but I suggest either "Physical Processes of the Interstellar Medium" by Lyman Spitzer (only small parts about magnetic fields) or "Plasma Physics for Astrophysics" by Russel Kulsrud.

wolram
Apr4-05, 03:21 PM
Thanks Space tiger, i think this is a under rated topic, and think it needs
more understanding, if any one has a deep understanding on this, i would
be greatful to hear from them.

Labguy
Apr4-05, 05:45 PM
Can anyone point me to some reference as to how magnetic fields are
produced in the inter stella medium please.Here are a few good links on that:

http://astronomy.sussex.ac.uk/~petert/ism2/magfield.pdf

http://www.bao.ac.cn/bao/hjl/xian/proceedings/Katia/fin/Katia.pdf

http://citebase.eprints.org/cgi-bin/fulltext?format=application/pdf&identifier=oai%3AarXiv.org%3Aastro-ph%2F0012301

http://www.aas.org/publications/baas/v36n5/aas205/1306.htm

http://flux.aps.org/meetings/BAPSMAY96/abs/S1335004.html

hellfire
Apr5-05, 03:18 AM
As far as I know there are two possibilites, and probably a combination of both leads to the generation of magnetic fields in galaxies. The first one assumes that the origin of galatic magnetic fields are primordial magnetic fields in the universe before galaxy formation. The collapse and compression of baryons would have compressed the line fields also, increasing the field strength (it is assumed that the field lines are ‘frozen’ and bound to the barionic gas). The second one is the theory of the galactic dynamo and assumes that the magnetic fields are generated due to turbulent motions which amplify in a preferred direction. As far as I know the first option alone leads to magnetic fields which are too strong compared with observations, and the second option alone leads to magnetic fields which are too weak in newborn galaxies, compared with observations.

wolram
Apr5-05, 11:59 AM
Thanks Lab guy, lots of lovely reading, should keep me busy for a while.
thanks also Hellfire.