Talk:L-shell

I believe that the extensive discussion about Charged particle motions in a dipole field, written by Wwheaton is beyond the scope of this article. If there is no objection, I intend to delete it and provide a link to the appropriate material at magnetic field. Drdan14 (talk) 00:02, 11 August 2010 (UTC)


 * Instead of deleting all of it, we could summarize it and link to the appropriate articles. We also have cyclotron resonance, providing adequate coverage of the topic elsewhere in the encyclopedia.  Nimur (talk) 00:30, 11 August 2010 (UTC)


 * Begging your pardons gentlefolk, I think an article entitled "L-shell" should aspire to describe what the thing is. That means describing the motion of charged particles in the dipole field, including their cyclotron orbits, their bouncing between mirror points, and their drift in longitude, so that they sweep out a surface.  Of course I will be ruled by consensus, but as this is a specialized article, I hope we can wait a while for other editors to weigh in.  Thanks -- Wwheaton (talk) 06:27, 11 August 2010 (UTC)
 * After re-reading the article, I don't think there was any "off-topic" content; all of it is encyclopedic and relevant. There is no need delete content unnecessarily.  Dan, what's your particular objection?  Is there a specific section or paragraph that needs to be more concise or rephrased?  Nimur (talk) 18:41, 11 August 2010 (UTC)
 * I suppose it was just too large a block of prose for my liking. Some figures would go a long way towards making the explanation more clear.  And maybe the title of the section can be changed to "Definition of L-shell in a non-dipole field" or something of that sort. Drdan14 (talk) 18:34, 18 August 2010 (UTC)

Other bodies
I like the suggestion that the article should be broadened to other bodies. The (B,L) co-ordinate system is general of course, and useful for all astronomical objects with strong nearly-dipole fields. Besides Jupiter, Mercury, Saturn, Uranus, and Neptune have significant dipole fields, while pulsars and accreting neutron stars are other obvious cases in point, as well as magnetic white dwarfs, though I am unfamiliar with the literature on these. It will be a while before we have more data for Uranus and Neptune, but Mercury and Saturn are rapidly becoming known. How to organize these needs discussion. Maybe case by case for the known objects, with a more general overview of planetary magnetospheres, including both the near-field discussed here, and the far-field where interaction with external flows and fields like the Solar Wind becomes important? Wwheaton (talk) 07:35, 11 August 2010 (UTC)
 * The important criteria is whether scholarly articles that use the terminology "L-shell" are being published about neutron stars, galactic nuclei, and so on. So far, I only found Jupiter- and Earth- articles.   Nimur (talk) 18:43, 11 August 2010 (UTC)