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Angular momentum loss from quadrupole EM radiation

  1. Jun 25, 2013 #1
    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.

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

    Someone has a comment on this ? Any reference ?
  2. jcsd
  3. Jun 26, 2013 #2
    Nobody knows anything about electromagnetic radiation here ?

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

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

    This is a standard well-known result.
    Last edited: Jun 26, 2013
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