1. Geometrical Measurements of the TEC Elements Goals internal survey external survey LINK calibration Means 3D CMM Cosmics Geodesy Procedure Conclusions A.Ostaptchouk, D.Pandoulas, S.Schael, R.Siedling I. Physikalisches Institut, RWTH-Aachen Talk presented by A.O. for the TK TPO meeting on 01.11.01

2. Geometrical Measurements of the TEC Elements - Goals - Goals of the geometrical measurements Internal survey: measurement of the TEC internal geometry External survey: measurement of positions of the TEC external fiducial marks w.r.t. the TEC internal coordinate frame LINK calibration: measurement of LINK element orientations

3. Geometrical Measurements of the TEC Elements - Goals - Internal survey: measurement of TEC geometry for  Quality Control (QC) of the TEC petals and discs  Precise (  50  m) measurement of module r  coordinates in petal coordinate frame to provide a starting point for alignment with tracks  Less precise (  100  m for r  -coordinates,  500  m for z-coordinates) measurement of petals in the TEC coordinate system to provide the starting point for the TEC optical alignment system

4. Geometrical Measurements of the TEC Elements - Goals - External survey: measurement of positions of the TEC external fiducial marks with  100  m precision for fiducial mark r  -coordinates, and  200  m precision for fiducial mark z-coordinates in the TEC coordinate system (for precise positioning of the TEC in the CMS coordinate frame) LINK calibration: measurement of LINK element orientations  20  rad precision for tiltmeter  -orientation w.r.t. gravity  100  rad precision for periscope  - and  -orientations in the TEC coordinate system

5. Geometrical Measurements of the TEC Elements - Means - Means of the geometrical measurements 3D Coordinate Measuring Machine (CMM) Cosmic Rays Geodesy

6. CMS Tracker Review September 2001 Geometrical Measurements of the TEC Elements - Clean Room - Parameters of Aachen clean room Class 100 000 Temperature control:  1 o C Humidity control:  10%

7. Geometrical Measurements of the TEC Elements - 3D CMM - 3D Coordinate Measuring Machine Type Wenzel RS-1618 Dynamic range 2500  1600  1800 mm 3 Precision 20 + (L/50 mm)  m  70  m Sensitive elements mechanical feeler or video camera

8. Geometrical Measurements of the TEC Elements - Cosmics Stand - Cosmics test-stand Triggered area 2200  2200 mm 2 Trigger granularity (10 X-counters)  (10 Y-counters)  -energy threshold 200 MeV (16cm steel)

9. Geometrical Measurements of the TEC Elements - Geodesy - CERN survey group (Ch. Lasseur) provides different geodesic measurements, e.g. photogrammetry: Dynamic range several meters Resolution 50 - 100  m

10. Geometrical Measurements of the TEC Elements - Internal Survey - Instruments: Survey of support structures 3D CMM Measurement of module positions Cosmics Targets for support structure measurements: Petals module inserts, petal mounts Discs petal inserts, reference spheres TECs reference spheres of the TEC discs Objectives of cosmics measurements: Module positions verification of the CMM survey System test one tower (1/16 TEC) read-out Optical alignment calibration: zero for installation

11. Geometrical Measurements of the TEC Elements - Survey of Petals - Procedure of petal survey: Petal position vertical Petal coordinate frame defined by 3 petal mounts Module insert positions in the petal coordinate frame Petal mounts Module inserts

12. Geometrical Measurements of the TEC Elements - Survey of Discs - Procedure of disc survey: Disc position vertical or horisontal Number of runs two overlapping runs Disc coordinate frame defined by 3 reference spheres Petal insert positions in the disc coordinate frame Reference spheres Petal inserts

13. Geometrical Measurements of the TEC Elements - Survey of TECs - Procedure of TEC survey: TEC position vertical or horisontal Number of runs two or three overlapping runs TEC coordinate frame defined by reference disc (e.g. #5) Disc positions in the TEC coordinate frame Reference spheres

14. Geometrical Measurements of the TEC Elements - Cosmics Stand - One tower (1/16 TEC) characteristics: Number of petals 9 Number of modules ~ 300 Number of FEDs 5-6 Cosmics rate ~.5 Hz To fulfill the goals of measurements with cosmic rays measurement of the Si-odule positions system test of the TEC calibration of the optical alignment the minimal subsystem which has to be fully operational on the cosmic stand is one tower

15. Geometrical Measurements of the TEC Elements - External Survey - Procedure has to be elaborated in a contact with the CMS survey group (Ch. Lasseur): Number of external fiducials Placement of the fiducials Measurement program Goal of the external survey: precise measurement of the TEC external fiducials in the TEC coordinate system for precise positioning of the TEC in the CMS coordinate frame Instruments: 3D CMM photogrammetry

16. Geometrical Measurements of the TEC Elements - LINK Calibration - LINK elements to calibrate: periscopes:  100  rad precision for  - and  - orientations in the TEC coordinate system tiltmeters:  20  rad precision for  -orientation w.r.t. gravity LINK System tiltmeters periscopes

17. Geometrical Measurements of the TEC Elements - Periscope Calibration - Periscope calibration: measurement of the sensor positions w.r.t. back-disc coordinate system using CMM or photogrammetry measurement of the laser spot positions in senor coordinate system

18. Geometrical Measurements of the TEC Elements - Tiltmeter Calibration - Tiltmeter calibration: measurement of the back-disc reference incerts w.r.t. gravity using CMM or geodesy registration of the tiltmeters readings

19. Geometrical Measurements of the TEC Elements - Conclusions - Geometrical measurements of the TECs provide necessary quality control of the TEC parts give a good starting point for both optical and track alignment make possible precise positioning of the TECs in the CMS coordinate frame allow calibration of LINK system elements The measurement tools are 3D Coordinate Measuring Machine Cosmic rays stand Photogrammetry The measurement procedures have to be developed and tested in contact with the CMS survey group