Accelerating Particle Radiation

[JFS321]

Guys, I'm looking for some checking of my own understanding about the EM waves given off by accelerated particles. Specifically, is this radiation only due to disturbances in a previously static electric field...therefore we are viewing this disturbance as a wave? Or, is there more to the story?

Also, I am wondering if Lenz's Law comes into play here. Are the induced EM fields being caused by the AC current also producing measurable waves? Thanks.

 

[Dale]

If you are thinking of accelerated point particles then the appropriate equations are the Lienard Weichert potentials

http://en.m.wikipedia.org/wiki/Liénard–Wiechert_potential

I am not sure which terms you would consider as representing disturbances in a previously static electric field.

 

[JFS321]

I think I should have stated time-varying changes in the field. Therefore, an observer outside of the field would see the varying field as a wave. (?) Is it correct to state that all em waves are formed in this manner?

 

[Dale]

Is it correct to state that all em waves are formed in this manner?

No, I don't think so. There are EM wave solutions which are vacuum solutions. If you make the assumption that all waves are formed in this manner then you get Jefimenkos equations, but that is an assumption and it ignores some valid solutions to Maxwell's equations.

 

[JFS321]

Thank you. Two last questions: Should I continue, then, with my understanding that a time-varying electric field is causing these waves observed from an AC current?

And, do the induced currents of Faraday/Lenz radiate measurably?

 

[Dale]

Thank you. Two last questions: Should I continue, then, with my understanding that a time-varying electric field is causing these waves observed from an AC current?

That seems fine to me specifically for the case mentioned.

And, do the induced currents of Faraday/Lenz radiate measurably?

Yes.

 

[tech99]

Guys, I'm looking for some checking of my own understanding about the EM waves given off by accelerated particles. Specifically, is this radiation only due to disturbances in a previously static electric field...therefore we are viewing this disturbance as a wave? Or, is there more to the story?

Also, I am wondering if Lenz's Law comes into play here. Are the induced EM fields being caused by the AC current also producing measurable waves? Thanks.

 

[tech99]

My understanding is that EM waves are caused when a charge accelerates, so that ripples occur in its static electric field. The B field arises when the electric wave passes an observer. I have also discovered that an accelerating magnetic pole (not a magnetic field) can also radiate in a similar way.