Resonant bond wire vibrations in the ATLAS semiconductor tracker

Dangerous mechanical resonances exist which can lead to the breaking of bond wires if time varying currents are passed through them in a magnetic field. The results of analytic calculations and an FEA analysis are described. The results of experimental investigations using wire bonds on test circuits are given. The possible effects within the ATLAS SCT were investigated and a fixed frequency trigger veto algorithm, designed to minimise the dangers of breaking wire bonds, was developed.