The multipole-expansion tag has no wiki summary.
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What is the magnetic quadrupole moment of a nucleus in cylindrical coordinates?
What is the magnetic quadruple moment of a nuclei in cylindrical coordinates?
The quadrupole moment of a nucleus is zero in spherical coordinates but in the cylindrical coordinates it can't be ...
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Forcing quadrupole moments to vanish for a neutral system
For a system of electric charges $q_i$, at positions $\mathbf{r}_i$, with a nonzero net charge $Q=\sum_i q_i$, one can define a "centre of charge" in the obvious way as
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Simple quadrupole moment
I have a very simple problem: There is a charge $-q$ at $(0, 0, d)$ and $(0, 0, -d)$ as well a charge $2q$ at $(0, 0, 0)$. I have to calculate the quadrupole moment using spherical coordinates. I use ...
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Center of charge in quadrupol tensor
In theoretical classical electrodynamics we defined the quadrupol tensor of $n$ charges $q_k$ at positions (from origin or center of charge, see below) $\vec r_k$ like so:
$$Q_{ij} = \sum_{k=1}^n q_k ...
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Computing a “best-fit” of discrete points from a multipole expansion, i.e. invert the multipole moments
Take a field $\phi(\bf{x})$ created from a charge distribution contained within a radius $R$. The multipole expansion in spherical harmonics $Y_{\ell,m}$ outside of $R$ is approximated by:
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all multipolar terms of nuclear fields must be confined?
When usually speaking about QCD confinement, one refers to the fact that color charges over lengths above the hadron size are fully neutral, which implies that monopolar charges over an extended ...
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quadripolar moment in curved space
So, i'm going over the Thorne's derivation of the quadrupolar radiation term, and they write the core term as:
$$ \frac{3 r_i r_j - 2 r^2 \delta_{ij}}{4 r^5} $$
But if i try to obtain this term by ...
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What is the physical meaning of the terms in the multipole expansion?
I have a few questions on multipole expansions and I have read about the topic in many places but could not find an answer to my questions, so please be patient with me.
The electrostatic potential ...
