Calibration of clinometers for the alignment of muon chambers in the CMS experiment. MOSCHOUTIS Thomas FAS meeting – Orlando, 12 March 2004

Global view of the Compact Muon Solenoid

View of one Disk Dual-axis clinometers for monitoring orientation of transfer pates:

Calibration bench CIinometer sensing Liquid calibrated Linear mover Θ

First setup Clinometer’s place Linear mover

Error calculation Error in φ: Error in φ: φ =Tan -1 (L/H)φ =Tan -1 (L/H) Δφ=(∂φ/∂L)*ΔL+(∂φ/∂H)*ΔH =(1/(L+H))*ΔL-2L/(H 2 +H*L)*ΔHΔφ=(∂φ/∂L)*ΔL+(∂φ/∂H)*ΔH =(1/(L+H))*ΔL-2L/(H 2 +H*L)*ΔH Using the same formula: Using the same formula: ΔΩ=(1/(L+M))*ΔL- 2L/(M 2 +M*L)*ΔMΔΩ=(1/(L+M))*ΔL- 2L/(M 2 +M*L)*ΔM Taking ρ=cos-1(M/K) and M=0 Taking ρ=cos-1(M/K) and M=0 Δρ=ΔM/KΔρ=ΔM/K So the total error is: So the total error is: Δθ =(Δφ 2 +ΔΩ 2 +Δρ 2 ) 1/2Δθ =(Δφ 2 +ΔΩ 2 +Δρ 2 ) 1/2 M K ρ φ L H

First test curve

Zero degree measurement Pendulum clinometer Long rod to get more precision

Problem induce by the plate thickness

Second test curve

The 6 different mounting plates Clinometer’s place

Next setup Linear mover Adapter Tilting base Mounting plate Click here to see movie