- #1
fluidistic
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Homework Statement
A charged particle of charge q with arbitrary velocity ##\vec v_0## enters a region with a constant ##\vec B_0## field.
1)Write down the covariant equations of motion for the particle, without considering the radiation of the particle.
2)Find ##x^\mu (\tau)##
3)Find the Lorentz transformation such that the motion of the particle is restricted to a plane.
4)Calculate the dipole term of the fields and the average radiated EM power by the particle.
Homework Equations
##\tau=t\gamma##
The Attempt at a Solution
1)##\frac{dp^\alpha}{d\tau}=qU_\beta F^{\alpha \beta}## would be my reply.
Where ##p^\alpha## is the four-momentum, ##U_\beta## is the four-velocity and ##F^{\alpha \beta}## is the electromagnetic tensor.
2)I solved the equation found in 1) by writing the tensors under matrix form. I got that ##x^\alpha=(ct,x^1(t),x^2(t),0)## where ##x^1(t)=\frac{mv_{0x}}{qB_0}\sin \left ( \frac{qB_0 t}{m} \right ) + x^1_0## and ##x^2(t)=\frac{mv_{0x}}{qB_0}\cos \left ( \frac{qB_0 t}{m} \right ) + x^2_0##. Now I just realize that they asked in terms of ##\tau## and not t. Well I get ##x^1(\tau)=\frac{mv_{0x}}{qB_0\sqrt{\gamma}}\sin \left ( \frac{qB_0\sqrt{\gamma}\tau}{m} \right )##.
3)I'm out of ideas on this one. I know I can express the tensor of the Lorentz transformation as a matrix (I guess this way: https://en.wikipedia.org/wiki/Lorentz_transformation#Matrix_forms) but I'm not sure what they're asking for when they ask for the motion to be in a plane. Isn't the motion already in the x-y plane in my case? I picked ##\vec B_0## as ##B_0\hat z## originally.