CERN/LHCC 2000-051
LHCC 49
11 December 2000

LARGE HADRON COLLIDER COMMITTEE

Minutes of the forty-ninth meeting held on
Wednesday and Thursday, 29-30 November 2000

OPEN SESSION:

1. ALICE Status Report: J. Schukraft

2. Report on ALICE Integration: L. Leistam
 

CLOSED SESSION:

Present: R. Cashmore, D. Cassel, J. Dainton, A. De Roeck*, H. Dijkstra*, J. Engelen (Chairman),
A. Ereditato, G. Goggi, J.-J. Gomez-Cadenas, Y. Karyotakis, M. Kasemann, U. Heinz*, P.-G. Innocenti*,
P. Lebrun, J. Lee-Franzini, B. L÷hr, J. Nash, M. Mangano, J. Panman, K. Potter, A. Rostovtsev,
P. Roudeau, T. Ruf, H. Schellman, K. Tokushuku, E. Tsesmelis (Secretary), G. Zech.
                 *) Part time
Apologies: B. Adeva, G. Altarelli, J. Carr, M. Delfino, L. Maiani, P. Sharp
 
1. INTRODUCTION
The Chairman welcomed the new member of the Committee.
The minutes of the forty-eighth LHCC meeting (LHCC 2000-043/LHCC 48) and the LHCC report on the CMS Comprehensive Review were approved without modification.2. STATUS OF THE LHC PROJECT The Director of Research for Collider Programmes presented the status of the LHC project. He reported steady progress on the construction of the LHC machine and as reported earlier, commissioning with single beam is currently scheduled to commence in July 2005. Working detectors of the LHC experiments should therefore be installed in time for the beginning of LHC operation in July 2005, although further detector commissioning and installation is foreseen beyond that date. A working group consisting of representatives from the machine and experiments is being set up to study the schedule. In particular, the feasibility and extent of a period with colliding beams at the end of 2005 requires further evaluation.3. REPORT FROM THE LHCb REFEREES The Committee heard a report from the LHCb referees, concentrating on the reviews of the Technical Design Reports (TDRs) for the Calorimeters and RICH. The Calorimeters will provide high transverse energy hadron, electron and photon candidates for the first level trigger, will identify electrons, essential to flavour tagging through semileptonic decays, and will reconstruct p0s and prompt photons thus giving access to B-meson decay channels which are important to the complete physics programme. Particle identification in LHCb will be achieved with the use of the ring-imaging Cherenkov (RICH) detectors. Their goal is to distinguish between pions and kaons in the variety of final states the experiment will have access to.  The referees also reviewed the status of the LHCb sub-detectors and reported on the overall schedule and milestones. No changes in the milestones were reported since the previous LHCC meeting and none of the known delays appear to be critical, although the construction of the calorimeters is on the critical path. The Collaboration is still committed to be ready for installation at Point 8 in mid-2004.4. REPORT FROM THE ALICE REFEREES The Committee heard a report from the ALICE referees, covering developments in the Pixel, Silicon Drift Detector (SDD) and Time-of-Flight (TOF) detectors, integration issues and the general schedule and milestones.  Good progress was reported on the ALICE1 Pixel chip and on the qualification of the SDD modules. The development of the strip detector for the TOF is progressing well and a detector test with discrete electronics from a commercial vendor provided promising results.  Moreover, it was reported that the Photon Multiplicity Detector (PMD) would be located at a new location from that described in the TDR. This has resulted in the design of some mechanics and electronics components of the PMD to be postponed since the detector granularity may need modifying when the detector relocated. The LHCC requests a written document from ALICE detailing the choice of the new location and its implications.  The LHCC Comprehensive Review of ALICE is confirmed for the January 2001 meeting of the Committee. Details of the general schedule, including updated milestones, will be presented at this review.5. REPORT FROM THE ATLAS REFEREES The LHCC heard a report from the ATLAS referees, concentrating on a follow-up to the Comprehensive Review of ATLAS held in July 2000. The report included points that were not covered during the Comprehensive Review and issues that were raised during this review.  A working detector for the first LHC run in 2005 requires full calorimeter coverage, most of the tracking detectors and a large component of the muon spectrometer. Some of the precision layers, the TRT outer end-cap and the external and mid-section muon chambers would be staged. This would allow the Collaboration to search for SUSY particles and for the Higgs, but would require about 10 fb-1 of integrated luminosity to be of significance. The detector will be completed during the 2005-2006 shutdown period, in time for the 2006 LHC run.  Delays in the Pixel schedule may lead to a Pixel system that is inserted after the beam pipe is in place. This would lead to a re-design of the detector and perhaps of the beam pipe. Furthermore, resource limitations may require that one layer of the barrel and two disks are staged by one year. The LHCC requests to be kept informed of any changes to the approved Pixel configuration. Moreover, while the Pixel detector is studying the possibility to go from DMILL to DSM for the front-end electronics, the TRT has decided to stay with DMILL as the baseline.  The referees also presented the status of the calorimeters and the muon chambers. Good progress was reported on the electrodes for the electromagnetic calorimeter although problems with the stacking of modules were reported. Moreover, the LHCC urges the Collaboration to calibrate the FCAL calorimeter in a test beam and to compare results to simulations. Good progress was reported on the muon chambers ˇ MDTs, CSCs, RPCs and TGCs.  The referees also reported on the ATLAS Trigger, DAQ and Computing. The estimated value of the trigger rates times event size was discussed and some uncertainty in these figures was reported. The LHCC urges the Collaboration to continue their efforts to make precise the projections as they will have an impact on the offline computing requirements.  Finally, the referees reported on the studies concerning the measurement of luminosity and on the CollaborationÝs long-term plans for test beams.6. LHCb CALORIMETER TECHNICAL DESIGN REPORT The LHCC has completed its scientific, technical, and cost evaluation of the LHCb Calorimeters TDR submitted in September 2000. The Committee was impressed by the quality of the work presented in the TDR and congratulates the Collaboration. The technology and design of the Calorimeters are well-suited for the detection of neutral pions, measurement of electron and hadron energies, and for separating hadrons and electrons and are adequate to achieve the physics goals stated in the LHCb Technical Proposal.  The Committee has no major concerns. An ancillary document (LHCC 2000-049) contains items of lesser concern as well as a list of agreed milestones for monitoring the progress of the project. The LHCC review was not an engineering review, although some engineering aspects of the project were presented and discussed with the referees. The LHCC recommends that LHCb follows the established practice of conducting an independent review of the engineering design. Written reports should be made available to the LHCC through its referees.  Recommendation  The LHCC recommends general approval of the LHCb Calorimeters Technical Design Report. The LHCC considers the schedule given in the TDR and the list of milestones in the ancillary document to be reasonable. They will be used by the Committee to measure and regulate the future progress of the project.7. LHCb RICH TECHNICAL DESIGN REPORT The LHCC has completed its scientific, technical, and cost evaluation of the LHCb RICH TDR submitted in September 2000. The Committee was impressed by the quality of the work presented in the TDR and congratulates the Collaboration. The technology and design of the RICH are well-suited for the identification of charged pions and kaons and are adequate to achieve the physics goals stated in the LHCb Technical Proposal.  The Committee has no major concerns. An ancillary document (LHCC 2000-050) contains items of lesser concern as well as a list of agreed milestones for monitoring the progress of the project. The LHCC review was not an engineering review, although some engineering aspects of the project were presented and discussed with the referees. The LHCC recommends that LHCb follows the established practice of conducting an independent review of the engineering design. Written reports should be made available to the LHCC through its referees.  Recommendation  The LHCC recommends general approval of the LHCb RICH Technical Design Report. The LHCC considers the schedule given in the TDR and the list of milestones in the ancillary document to be reasonable. They will be used by the Committee to measure and regulate the future progress of the project.8. REPORT FROM THE CMS REFEREES The LHCC heard a report from the CMS referees, concentrating on developments since the recent Comprehensive Review. The CMS schedule foresees having a working detector operational in time for the first LHC run in 2005. The detector assembly and commissioning will be completed during the 2005-2006 LHC shutdown period, in time for the 2006 LHC run. The list of milestones developed from this schedule will be presented to the LHCC for approval at its January 2001 session.  The referees also reported on the status of the electromagnetic and hadronic calorimeters (ECAL and HCAL). The critical path of the ECAL project lies with the procurement of the crystals and APDs. Good progress was reported on the crystal production in Russia. Moreover, the first batch of crystals from China is being delivered to CMS and the acceptance criteria for these crystals are being defined. An effort is being made to keep to the required crystal delivery schedule. Difficulties with accelerated ageing of the APDs was reported but an intensive effort is being made by the manufacturer to resolve this issue. The Committee notes that the failure of one APD would result in the loss of information from the whole crystal and urges CMS to re-consider this issue.  Good progress was reported for the HCAL absorber and scintillator, but it was noted that the QIE electronics is on the critical path and the new design of the HPD has not completely solved the problem with the electronics cross-talk. The schedule of the HPDs should be closely monitored as the procurement of these devices is approaching the critical path. The QIE schedule should still match the overall HCAL schedule as long as FNAL maintains its engineering effort, and there is not more than one failure in the upcoming ASIC submission.  The engineering design of the HF calorimeter has been transferred to FNAL and an Engineering Design Review is scheduled for March 2001. The HF is on the critical path as it is now considered to be part of the working detector to be installed for the first LHC run in 2005.  The referees also presented the status of the Tracker project. The recent Engineering Design Review of the Tracker provided the endorsement to start the tender actions for the silicon sensors and modules and to conduct a system test using sensors from the `Milestone 200Ý effort. Moreover, additional information clarifying the lay-out of the Tracker was presented. In case of any financial shortfall, the Collaboration proposes to omit one stereo silicon layer in the Outer Barrel of the configuration approved by the LHCC in May 2000. The LHCC urges the Collaboration to perform simulation studies of the pattern recognition and track recognition capabilities of such a Tracker.  Finally, the referees reported on the status of the muon system. A delay of at least six months has been reported for the barrel Drift Tubes (DTs) and a new schedule was presented to the LHCC. It was reported that extra production capacity is being set up in Torino, which will help recover the delay. Moreover, whereas the tooling is ready at CIEMAT, that provided by Aachen and Padova is still in the commissioning phase, causing some delay in the overall project.  A delay in the CSC electronics is noted. The difficulty is associated with the frequency of Single Event Upsets leading to the necessity of regularly resetting the FPGA. The electronics are considered to be on the critical path of the overall CSC project.  Further studies on the use of linseed oil and on the option of double-gap chambers for the RPCs are underway. A decision is needed as soon as possible and a further report will be made at the January 2001 meeting of the LHCC following9. COST REVIEW OF LHC EXPERIMENTS P.-G. Innocenti presented details of the cost review of the ALICE, ATLAS and CMS experiments. The report focused on the work performed to finalize the review started in September 2000.  The ALICE Memorandum of Understanding has been recently signed and the costs are at present in accord with what has been presented in the TDRs. Moreover, the review concluded that both ATLAS and CMS are following strict budget control and should be commended. The conclusions of the review will be presented to the subsequent sessions of Council and Resource Review Boards (RRBs).10. REPORT FROM HELSINKI WORKSHOP ON FORWARD PHYSICS AND LUMINOSITY DETERMINATION
      AT THE LHC  De Roeck reported on the very successful First Workshop on Forward Physics and Luminosity Determination at the LHC held in Helsinki in November 2000. The workshop attracted 45 participants, consisting of representatives from the LHC accelerator and detectors as well as theorists. The issues discussed were forward physics (diffraction, low-x physics and QCD and gg physics), together with methods in measuring the luminosity.  Among the conclusions of the workshop was that a rich programme of forward physics is available at the LHC and the interested community is encouraged to develop ways of exploiting it. Moreover, given the experience at the Tevatron, it is recommended that two experiments measure stot and methods to measure the luminosity based on QED processes should be developed further.  Further details may be found at URL: http://fwdlhc.home.cern.ch/fwdlhc. Future workshops will also be organized as well as a joint LHC machine and experiment meeting at CERN to discuss a coherent forward physics and luminosity measurement strategy.11. TEST BEAMS T. Ruf presented a status report on the SPS and PS Fixed Target Programmes. He reported on the special CMS-ECAL test performed successfully at the end of the heavy-ion run with the help and cooperation of NA57, NA49 and the SL-EA group.  He also showed the machine schedules for 2001, which have now been approved by the Research Board. Twenty-nine weeks are foreseen for the PS, from 2 April to 5 November, while 16.5 weeks are scheduled for the SPS proton run from 12 July to 4 November. There will be no heavy-ion run in 2001. The SPS supercycle length will lengthen to 16.8 s. and the flat-top will be extended to 5.2 s. Based on these machine schedules, the draft schedule for the PS East Hall has been prepared and that for the SPS is being finalized.  Finally, he showed the projections for the years 2002-2004. In general, the projected beam time requests exceed the available time. Moreover, the Research Board approved the heavy-ion runs for 2002 and 2003.  J. Engelen thanked T. Ruf for his work as SPS and PS co-ordinator, from which he retires at the end of 2000. His efforts have been essential to the successful definition and operation of the LHC test beam activities.12. DATES FOR 2001 LHCC MEETINGS 31 January ˇ 1 February
21-22 March
16-17 May
4-5 July
3-4 October
21-22 November
The LHCC received the following documents * Restricted circulation only
 
 
  Emmanuel Tsesmelis
e-mail: LHCC.Secretary@cern.ch
Tel. 78949, 164057
LHCC Secretariat: Janet Grant (Bldg. 14/4-022) Tel. 73424
                               e-mail: Janet.Grant@cern.ch