C-V Measurements

1
RICH1 B-field Measurements
HPD image distortions in a magnetic field.
The RICH1 magnetic shield in place in the cavern
The RICH1 detector
Finite Element Model of the field in RICH 1
Vector field measurements every 10 cm around the
HPD plane.
Maximum field in HPD plane 24 Gauss Horizontal
symmetry in the plane (1 Gauss)
L1 Trigger requirements on the magnetic field
Difference to model (Gauss)
Integrated B field Measured 127 kGauss
cm Predicted 138 kGauss cm
Conclusions Measurements 10-20 lower than FEA
model predictions Max field in HPD plane less
than 24 Gauss (requirement less than 30 Gauss)