[MCH] fix wire position on station 1 #13983
Merged
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The position of the anode wires in the local coordinate system of the quadrants of station 1 is different w.r.t. the other stations. For station 1, the origin of the system is on top of a wire, while it is shifted by half the pitch for the other stations.
I observed that by looking at the cluster charge asymmetry between the 2 cathodes as a function of the cluster position w.r.t. the closest wire. The pattern was inverted for station 1 w.r.t. other stations and w.r.t. the expected pattern.
I also checked with Christophe on a picture of an open quadrant of station 1. The position of the wires w.r.t. the center of the pads on the non-bending cathode was shifted by half the pitch in MC.
I checked that the effect is negligible on the efficiency and resolution in MC, although it has some effect on the number of pads fired, mostly on the non-bending cathode.