[Getdp] 2D axisymmetric magnetostatics

[Stepan Roucka]

Hello everybody,
I am designing a magnetic adiabatic collimator and
I need to compute the electrostatic and magnetostatic
field in the apparatus. I have a problem with computing
the magnetic field in axial symmetry. I adopted an
example from the wiki with vector potential formulation.
I use the Form1P function space with zero Dirichlet BC
on axis an on the domain boundary (finite domain for now).
The resulting B field is very noisy especially close to the
axis (as illustrated by the attached plot of B magnitude).
Moreover, the shape of magnetic fields looks ok, but the
value is approximately 300 times smaller in comparison
to the results of FEMM.

Could someone please tell me what am I doing wrong?
My project files are attached.

Thanks in advance
Stepan Roucka
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