Take a 10 keV ion in the van Allen belts 1000km above earths surface in a dipole magnetic field of 100 Gauss. Estimate the grad-B and curvature drift if the particle is a proton and compare this drift with the gravitational drift.(adsbygoogle = window.adsbygoogle || []).push({});

3. I know all the formulas needed, but do not know what the B field would be. Do i use spherical co-ords? In which case B would equal ( [tex]\frac{\mu}{4\pi}\frac{2M}{r^{3}}cos\theta[/tex] , [tex]\frac{\mu}{4\pi}\frac{2M}{r^{3}}sin\theta[/tex] , [tex]0[/tex] ) where M is the magnetic moment of the earth? Then put R=([tex]R[/tex] , [tex]0[/tex], [tex]0[/tex] )? Or am i on the wrong tracks entirely? Any hints greatly appreciated.

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# Homework Help: Guiding Centre, curvature drift (astro phys)

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