SimPEG.electromagnetics.static.spontaneous_potential.CurrentDensityMap

class SimPEG.electromagnetics.static.spontaneous_potential.CurrentDensityMap(mesh, active_cells=None)

Bases: LinearMap

Maps current density to charge density accumulation rate.

Parameters:

meshdiscretize.base.BaseMesh

active_cellsindex_array, optional

Defaults to all cells being active. This is used to apply a 0 Nuemann boundary condition at topographic faces.

Notes

This map relates current density \(\vec{j}_s\) in A/m^2 to the charge density accumulation rate \(q\) (C/(s m^3)) by taking the negative divergence.

\[q = -\nabla \cdot \vec{j}_s\]