CERN Photogrametry and Cocoa Reconstruction of EMU ISR Setup



COCOA is non-linear least squares fit program designed to simulate the behavior of optical objects being used by CMS.The COCOA code has been recently modified to support the CMS EMU DCOPS sensors.The FNAL EMU alignment group has used COCOA in the simulation and reconstruction of DCOPS sensors.




In addition to the calibration parameters required by each of the DCOPS sensors the reconstruction of an event, a set of measurements corresponding the the centroid of the laser in a particular CCD is required.The location of the centroid is the only non-constant parameter being inputted into COCOA at this time (MAB data will follow soon).Centroid locations are read into COCOA from a file prepared from FLAP output.




Note:Some files may require a PostScipt viewer, MS Excel, or Adobe Acrobat to be seen properly.



Link to COCOA Documentation (sparse)




COCOA Input Data (preparation of FLAP data)



Summary of FLAP fit data used to determine criteria for COCOA fit quality is here.

 

Summary of working CCDs based on determination of above criteria :

 

·July Laser 302 data

·July Laser 303 data

·Sept Laser 302 data

·Sept Laser 303 data

 
 

COCOA Output

 
 

COCOA derived sensor locations from CERN Photogrametry are located here (updated Dec 11, 2000).

 
 

Photogrametry and CMM Data used in Reconstruction

 
 

Final FNAL CMM Measurements of Sensor Brackets and MAB Bracket (updated Aug28, 2000)

·CMM PG Target - Dowel Relationships (.pdf)

·Mechanical Sensor Positions in ISR (.pdf)

·CMM PG Target - Dowel Relationships for et2 MAB mount (.pdf)

 

Extracted CERN Alignment Photogrametry Used to Determine Sensor Locations (updated Jan 24, 2001)

·Table of PG Target Locations (.pdf)

·Excel File of PG Target Locations (.xls)

 

Original CMS EMU Alignment Photogrametry In ISR Hall (all targets) (updated Aug 28, 2000)

·Postscript Report (.ps)

·Excel File of PG Target (.xls)

 

Original CMS EMU Calibration of MAB (final July position - updated Aug 28, 2000)

·Postscript Report (.ps)

·Excel File of PG Target (.xls)

 
 
 

You can find older CMS ISR Photogrametry Data at the CERN PG Group web site here.

Updated Jan 24, 2001 by RL