LHCC referees’ questions, comments, requests

1. LHCC referees’ questions, comments, requests • General: • 1. Production milestones should be established at the 10% and 50% level in order to be able to monitor production progress. • Production milestones at 10% and at 50% levels are appropriate for • Photon detectors • Readout electronics • Mirrors See MILESTONES • 2. Engineering Design Reviews should be held before construction starts. • These should be done at a level of formality consistent with the magnitude of the construction projects and the level of technical risk. The outcomes of the EDRs should be reported to the LHCb Referees. • Review procedures, to be held before construction starts, are proposed for: • Mechanics and optics • Photon detectorsReadout electronics See REVIEW PROCEDUREsGas systemSafetySoftware

2. LHCC referees’ questions, comments, requests • 3. Costs should be given in CHF that have been corrected for inflation to the proper year(s). The proper procedure for doing this should be established in discussions between LHCb and the Director for Collider Programmes. • The discussion has taken place and the procedure agreed. • Costs have been given (CORE tables) in year 2000 prices • Total RICH cost: 7,700 kCHF (cf 7,670 in TDR) • RICH: • 4. Will aging be a problem with the aerogel and has enough attention been paid to this question? Things that may lead to aerogel aging that should be investigated include: • * radiation damage, • * change of index of refraction with absorption of water, and • * changes in light transmission. • Clara Matteuzziwill present present results from measurements (made by LHCb and at KEK) on both hydrophobic and hygroscopic aerogel. These measurements include the effects of radiation damage and of water absorption on transmission and refrective index. • A future LHCb programme of measurements will be outlined.

3. LHCC referees’ questions, comments, requests • 6. How realistic is the RICH reconstruction when backgrounds such as muon halo are included? • Guy Wilkinson will present results from studies of RICH particle ID performance in presence of backgrounds, including the effects due to the estimated muon halo. • 7. Dates and milestones more specific than Q1, Q2, etc., should be provided. • Milestones given by month See MILESTONES • 8. Since the initial state is pp with charge +2, backgrounds in the RICH should contain more positive particles than negative particles. • Is this likely to introduce any apparent CP asymmetries that will not be handled with inversion of the magnet? • Is this likely to introduce any apparent CP asymmetries that will not be handled with inversion of the magnet? • Guy Wilkinson will review the way in which charge asymmetries can influence the measurement of CP violating asymmetries, and the methods which are available to measure and control these charge asymmetries, induced either through the detector or the initial state +2 charge.

4. LHCC referees’ questions, comments, requests • 9. Concerns with the delay for chip verification at IBM were expressed.This was really more of a concern for all of CERN -- not only LHCb. • Two obvious questions were asked: • * Will this be a problem in the future? • * Can anything be done about it? • However, overnight Peter Sharp looked into this and found that the relevant software was now available at CERN, so this need not be a problem in the future. Clearly the LHCb group should make use of this new software where appropriate. • Thierry Gys/Ken Wyllie will report on this issue and on the status of the • pixel chip testing.

5. Milestones for LHCb RICH detectors (1) Mechanics and optics: mechanical designs completed: March 2002 mechanics and optics completed: December 2003 begin assembly RICH-1 in IP8: January 2004 begin installation RICH-2 in IP8: July 2004 Photodetectors: prototype HPD completed: December 2000 place HPD order: September 2001 production/testing completed: March 2004 Readout electronics: prototype chain tests completed: May 2002 production/testing completed: January 2004 RICH detectors: commissioning completed: July 2005

6. Milestones for LHCb RICH detectors (2) Production milestones: Photodetectors: (468 units) 10% December 2002 50% June 2003 Level-0 Readout electronics: (242 units) 10% July 2002 50% March 2003 Level-1 Readout electronics: (60 units) 30% December 2002 60% June 2003 Mirrors: (120 units) 10% September 2002 50% January 2003

7. Review Procedures (1) • Reviews (Production Readiness Reviews) will be held before production starts. • Review procedures will involve experts, external to the LHCb RICH group. • Where established procedures exist we will use them. • Recommendations to LHCb Technical Board and reported to LHCb referees. • Mechanics and Optics: • Review panel to include an external engineer (eg: NIKHEF, RAL) • and an engineer from the LHC vacuum pipe group. • Preliminary (informal) review August 2001 • Production Readiness review January 2002 • Photon Detectors: • Review panel to include external photon detector expert(s) • Informal review January 2001 • Production Readiness review November 2001

8. Review Procedures (2) • Established Procedures exist for: • Readout Electonics: • RICH readout electronics will be reviewed through the procedures set up by the LHCb Electronics Coordinator. The first formal review will take place early in 2001. • Gas System: • The Production readiness review for the LHCb RICH gas system will involve the LHCb Gas Coordinator and the LHC gas group, which has responsibilities covering the 4 LHC experiments. • Safety: • Safety issues are the responsibility of the LHCb GLIMOS. The LHCb RICH project will be under continuous review by the CERN TIS (Technical Inspection and Safety) Commission. • Software: • In common with all LHCb sub-detectors the RICH specific software will be reviewed by the procedures implemented by the LHCb Computing Coordinator.