Goal : • Setup and monitor “chambers” with

resolution of < 200 m• Demonstrate System RedundancyTest Setup :• 1 SLM Line (2 Laser Redundancy)• 1 Transfer Line (Single Laser)• 1 Transfer Plate• Analog Sensors (Temp, Proximity)Data Analysis :• 1500+ Events Reconstructed• 3 Test Periods (July, Aug, Sept 2000)New Analysis Software :• CMS Object oriented Code for Optical

Alignment (COCOA) Prototype Reconstruction Software Used

EMU Alignment ISR Prototype System Test

June-Sept 2000 at CERN ISR Tunnel

Assumptions :• Sensors et2, et3, and es10 are known (In practice, es9 is used due to potential survey errors in es10)

• Transfer Plate definition is defined• Rotations of sensors are known within error limits of photogrammetry

Prototype Test SetupJune-Sept 2000 at CERN ISR Tunnel

Final ISR Results of COCOA Reconstruction for July/August and September Runs Using es9 as the Final Reference Sensor

COCOA Reconstruction Results(ISR Test Results – es9 Reconstruction)

Title:

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Final Results :• System = 133 m

•Typical Reconstructions within 300 m of expected survey location

• Sensors outside 300 m range have understood errors

Reconstruction Dominated By Survey Errors

• Estimated Survey Errors60 m local 120 m global

• Errors in COCOA Reconstruction220 m Systematic Errors

< 15 m Statistical Errors (1500 Events)

General Remarks • Reconstruction is roughly independent of

laser choice (within error)

• Reconstruction is independent of laser motions

• 4 CCD measurements on reference Sensors will be critical (we had 3)

ISR Reconstruction ResultsConclusions

COCOA Simulation

Goals• Create Model CMS EMU Alignment

System– DCOPS + Analog Sensors

• Evaluate Intrinsic System Errors– Chamber construction

– System design

• Evaluate System Performance– Intrinsic Resolution

– Correlation of System Components

– Effects from component failure

• Provide ‘First Draft’ of EMU Alignment Reconstruction Software

• Integration of Results into General Physics Simulation

Current Status (May 2001)

• Substantial Software Improvements• Extraction of Component Data from

CMS Production Drawings (Complete)

• Endcap CSC and SLM Lines have been modeled

COCOA Simulation

ME2/3/4 COCOA Model Simulated SLM Line