Angular momentum loss from quadrupole EM radiation

AI Thread Summary
The discussion centers on finding the general formula for angular momentum radiated from quadrupolar electromagnetic radiation, as existing sources primarily cover dipolar contributions. A proposed formula for angular momentum loss is presented, derived using dimensional analysis and energy considerations. The formula is dL_i/dt = - (1/90) (1/4πε_0c^5) ε_{ijk} ddot{Q}_{jl} dddot{Q}_{lk}. The user seeks confirmation and references regarding this formula, indicating a lack of information on electromagnetic radiation in the forum. The energy radiated from the quadrupole contribution is noted as a well-established result.
Barnak
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I'm looking for the general formula for Angular Momentum radiated away from quadrupolar electromagnetic radiation. I searched the usual books (Jackson, Landau-Lifchitz, ...) and just found the usual dipolar contributions.

Using dimensional analysis and energy radiated away, I found this formula, but I need a confirmation that it's the right one.

\frac{dL_i}{dt} = - \frac{1}{90} \, \frac{1}{4 \pi \epsilon_0 c^5} \, \varepsilon_{ijk} \; \ddot{Q}_{jl} \; \dddot{Q}_{lk}.

Someone has a comment on this ? Any reference ?
 
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Nobody knows anything about electromagnetic radiation here ?

For reference, the energy radiated away from the quadrupole contribution is

\frac{dE}{dt} = -\: \frac{1}{180} \, \frac{1}{4 \pi \varepsilon_0 c^5} \; \dddot{Q}_{ij} \; \dddot{Q}_{ij}.

This is a standard well-known result.
 
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