Simulation of MWPC with pads readout

Dear community,

I need to simulate a MWPC (Multi-Wire Proportional Chamber) with pad readout. Here’s a description of my setup:

I have two parallel anode plates, each with an area of 2×2 cm. (In the actual detector, the area will be much larger — I’ve chosen this small size to ensure I capture the full induced signal from the avalanche.) One of the anode plates is segmented into pads, each measuring 0.4×0.4 mm, giving a total of 50×50 pads. These pads will eventually be connected to a strip readout structure, but for now, think it is not important. The distance between the plates is 6 mm. At the center of the gap, I have 5 cathode wires.

The main challenge is to calculate the induced signal on each individual pad.

I initially tried using ComponentAnalyticField for this purpose. However, this method returns an integrated induced signal on the full (not segmented) anode that is more than an order of magnitude larger than the summed signal over all pads. I suspect this discrepancy arises because ComponentAnalyticField uses a parallel plate approximation for calculating the weighting fields of individual pads, which is inadequate in my case.

I’m now attempting to use Gmsh and Elmer to obtain both the electric field and the weighting fields. However, I’m currently stuck on how to efficiently compute the weighting fields for such a large number of pads.

Could someone recommend the best approach to simulate this kind of setup? Any suggestions or examples would be greatly appreciated.

Welcome to the ROOT Forum!
I’m sure @hschindl can give some hints

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