1. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 1 The CMS ECAL Endcaps Crystal ECAL Endcap Calorimeter (EE) Preshower EE

2. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 2 CMS ECAL Endcap, EE UK Involvement Design and assembly of the EE The UK has led the EE project since its inception: - detailed Monte Carlo simulations - optimisation of the physics performance - research and development of Vacuum Photo-Triodes (VPTs) - detailed mechanical design and systems integration - testing of Supercrystals (SCs) in beams at CERN The UK is responsible for - completing the detailed design and systems integration - procurement and testing of VPTs - design and procurement of the VPT HV system - procurement of the mechanical structures for the detector - assembly of 50% of the SCs

3. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 3 Vacuum Photo-triodes (VPTs) 25.4 mm Testing 1.8T at RAL 4T at Brunel Production proceeding to schedule 4000 devices per annum Last delivery Q4 2005 Concerns: anomalous devices, 6% of production.

4. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 4 EE Crystals EE crystals larger than the barrel crystals Shallower taper- different light collection - no depolishing 100 prototype crystals evaluated in 2001 - results fed back to producer 100 pre-production crystals received in 2003 - under evaluation at Imperial and Brunel Aim to place order for EE crystals by end of this year Crystals on critical path

5. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 5 EE SC mechanics Design complete Contract 15,000 inserts 600 interface plates 600 housings Completed by Electro-Mec (Reading) Ltd in Oct 03. Interface plate and housing Concerns Late EE crystal delivery SC mass production not before Q4 2005 Inserts

6. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 6 EE large mechanics progress Design complete for Backplate Ring flange Positional spacers Contract signed with TM Engineering, UK Phase 1 test pieces successfully completed at TM to specification Nov 2003. Positional spacers Sample backplate Dummy SCs

7. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 7 EE electronics integration Remaining major design task Detailed design for the integration of electronics and services on the back of EE Concerns: Complex area Requires input from other sectors of ECAL Need to pre-order cable looms etc well before parallel Dee assembly in 2006

8. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 8 EE Calibration at test beam UK has demonstrated that the design meets the performance specifications of CMS Combined crystal plus preshower response to electrons at 180 GeV Resolution 0.62%

9. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 9 EE planning

10. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 10 EE planning Complete EE-1 in Q2 2007 with reduced testing/calibration on Dee4

11. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 11 CMS EE Conclusions Design for EE system integration and preparation for mass production top priorities. The mass production of SCs and the assembly of 4 Dees in 2006 will require a smooth transition from ECAL Barrel to ECAL Endcap production. UK seeking and encouraging other CMS ECAL institutes to participate in the mass production and assembly. Uncertainty on EE crystal delivery THE major concern UK successfully undertaking its deliverables to CMS - VPT procurement, test and appraisal - SC and large mechanics design and procurement - HV system design

12. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 12 Additional info follows, next slide

13. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 13 VPT response in magnetic field Characteristic response of VPT –vs angle at B = 1.8T –vs magnetic field at angle of 15  –nb: flat response v field above 1T 8  -24  in CMS

14. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 14 Measured yield in 1.8T field Measured yield –In 1.8T field –Mean over 8  -24  –Converted to electrons/MeV VPTs meet CMS requirements Good correlation with measurements at 0T and 4T

15. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 15 Measurements in different B fields Manufacturers measure p & g at 0T –pg well correlated with yield at 1.8T Sample testing at 4T using Brunel Univ superconducting solenoid –Good correlation with 1.8T data

16. CMS-UK Oversight Committee 18/11/03 D.J.A. Cockerill - RAL 16 Relative gain at 4T