Feature request: plane-segmented tallies

[tjlaboss]

Description

MCNP allows tallies to be segmented by surfaces. MCNP 6.3.1 Manual § 5.9.14:

This is advertised as an alternative to creating many cells for tallying, but it is far more useful for surface current tallies: e.g., finite cylinders or polygon faces. Consider the following illustration: we are interested in the surface current on the part of the plane between A and B in blue, but not the crossings in red.

Alternatives

• This can already be accomplished for rectilinear, cylindrical, and spherical geometries with a MeshSurfaceFilter.
• This can be simulated using a CellFromFilter by creating a cell opposite every segment. However, this becomes very messy and tedious as you increase the number of segments.

Compatibility

The enhancement will add something new, presumably a Filter type.