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moving charge in medium

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Hello world,

I would like find the electric E(x,y,z,t) and in the magnetic field B(x,y,z,t) (depending on the time) around a particle moving with velocity v along the z-axis in a homogenous medium with a given electric permittivity and magnetic permeability. The particle is an ion represented by the charge density rho(x,y,z,t) = rho_0*exp(-(x+y))*log(z-2*v*t). Also, the particle has a relativistic movement (v ~ c).

My idea is to use the full Maxwell's equations and a current source J(x,y,z,t) = rho(x,y,z,t)*v.

In my opinion, I have two way to do it using COMSOL :

- use the general PDE mode to solve the system of equations coupling E, B, J obtained after some operations on Maxwell's equations...;

- use the AC power electromagnetics mode but the problem is that the fields must have (I read the COMSOL's book) an harmonic variation in time in the form : exp(iwt) but unfortunately it is not the case in my specific problem !!
Have you an idea to solve my problem ?

Thank you for your help !

Antoine

0 Replies Last Post Dec 15, 2011, 4:15 p.m. EST
COMSOL Moderator

Hello Antoine Martinez

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