CERN/LHCC 2004-016
LHCC 70
13 May 2004

 
LARGE HADRON COLLIDER COMMITTEE

Minutes of the seventieth meeting held on
Wednesday and Thursday, 12-13 May 2004

OPEN SESSION:             1. LHC Status Report: Lyn Evans

             2. Letter of Intent — Measurement of Photons and Neutral Pions in the Very Forward Region of the LHC: Yasushi Muraki

             3. ATLAS Status Report: Peter Jenni

             4. Letter of Intent — ATLAS Forward Detectors for Luminosity Measurement and Monitoring: Per Grafström

             5. Letter of Intent — Heavy Ion Physics with the ATLAS Detector: Barbara Wosiek
 

CLOSED SESSION:

Present: S. Bertolucci, K. Borras, M. Calvetti (Chairman), A. Ceccucci, J. Engelen, J. Feltesse, F. Ferroni*, M. Hauschild,
             M. Jaffre, Y. Karyotakis, V. Kekelidze, Y.-K. Kim, J. Knobloch, M. Mangano, J. Martin, P. McBride, K. Potter*,
             D. Schlatter, P. Seyboth, H. Tiecke, E. Tsesmelis (Secretary), C. Vallée, T. Wyatt
 

                                                                                                                                *) Part time

          1. PROCEDURE
    The minutes of the sixty-ninth LHCC meeting (LHCC 2004-011 / LHCC 69) and the report from the ALICE Comprehensive Review (LHCC 2004-012 / G-072) were approved without modification.

    The Chairman thanked the outgoing member Y.-K. Kim for her dedication and invaluable assistance.
     

          2. REPORT FROM THE CHIEF SCIENTIFIC OFFICER
    The Chief Scientific Officer (CSO) informed the LHCC on the status of the LHC Project. Given the delays in the installation of the LHC machine caused by difficulties in the QRL cryoline, the overall machine installation schedule is presently under review. A revised LHC machine installation schedule will be released once the situation with the QRL cryoline has been fully evaluated.

    In addition, he reported on the cost overrun for the CMS Electromagnetic Calorimeter crystals and noted that the situation is being discussed with the funding agencies.
     

          3. REPORT FROM THE ATLAS REFEREES The LHCC heard a report from the ATLAS referees, concentrating on general progress in the detector construction, and reports on the Inner Detector and the Letters of Intent on the Forward Detectors for Luminosity Measurement and Monitoring and for Heavy Ion Physics with the ATLAS Detector.

The referees reported on the status of the ATLAS magnets. The LHCC noted problems related to non-conformities found during preparation of the welding for the vacuum welds of the BT magnet. A major re-working of the welds is required in order to ensure leak tightness. This has caused a further three month delay in the schedule. The delay has become critical for the overall installation schedule as the first coil will only be installed in the ATLAS underground cavern in September 2004, several months behind the original schedule. Preparations are ongoing for the installation of the BT coils including a manipulation test with an iron structure simulating the BT coil dimensions. The LHCC took note of the recent problems with the ECT magnets. Problems with a bad batch of resin have resulted in only 8 of 16 coils having been impregnated. Moreover, certification for the cooling pipes has not been met by the firm and substantial financial claims for over-costs have been put forth by the manufacturer. ATLAS expects that the cold mass for ECT-1 will still be ready at the end of 2004. Good progress was reported on the solenoid magnet. The magnet has been inserted in to the cryostat and cool-down has started.

The Committee heard a report on the Inner Detector comprising the Pixel, SCT and TRT detectors. Production of all components is well-advanced and series production of the modules has started. Integration of the Inner Detector and their common infrastructure is progressing well. Good progress was reported on the Pixel Detector. Production of the SCT is in progress. The time taken to repair the module support brackets of the Barrel SCT has resulted in there being no float left in the detector’s installation schedule while the production schedule for the End-cap SCT remains tight with only three and two months of float remaining in the schedule for the completion of the End-cap C and End-cap A, respectively. Problems related to de-lamination of components for the TRT Web-circuit front-end electronics have been resolved. Assembly of the TRT is well underway but the TRT End-cap A has only two months of float left in the schedule.

The LHCC took note of the good progress in the ATLAS Trigger and DAQ projects. The Committee will, however, continue monitoring progress in the RPC Coincidence Matrix ASIC (CMA) on-detector electronics and the TGC Slave Board ASIC (SLB) read-out electronics.

The Committee heard a report on the ATLAS Letter of Intent on Forward Detectors for the Luminosity Measurement and Monitoring (LHCC 2004-010 / I-014). ATLAS proposes to complement their main detector with ultra-small-angle detectors based on Roman Pot inserts in the beam pipe, equipped with position sensitive detectors and located at 240 m on either side of the main ATLAS detector, to measure elastically scattered protons in the theoretically well-calculable Coulomb scattering regime for the primary purpose of the absolute determination of the LHC luminosity at the ATLAS interaction point. In addition, ATLAS proposes a luminosity monitor based on cylindrical Cerenkov counters placed around the beam pipe close to the ATLAS interaction point. The proposed detector, called LUCID (LUminosity measurement using a Cerenkov Integrating Detector), will monitor the number of inelastic pp interactions in each bunch crossing by counting the average number of particles detected per bunch crossing. The LHCC encourages the ATLAS Collaboration to continue the development of their experimental design of the Forward Detectors with a view to submitting a Technical Design Report. Future work should include development of the technical design of the detectors and an Engineering Change Request concerning the installation and integration of the Roman Pot system in the LHC Machine. The interface between the Forward Detectors and the LHC Machine will be followed-up in LEMIC.

The referees also reported on the ATLAS Letter of Intent on Heavy Ion Physics with the ATLAS Detector (LHCC 2004-009 / I-013). The Letter of Intent details first and preliminary studies to establish the performance of the baseline ATLAS experiment, as described in the approved Technical Design Reports, in the field of heavy-ion physics and the experiment’s capability to provide measurements to constrain the underlying physics. The accent of the studies is on high-pT signatures, which are better matched to the ATLAS design concept than the soft final states. No changes to the detector under construction, except for the possibility of the addition of a Zero Degree Calorimeter in the very forward regions to improve studies of ultra-peripheral collisions, are assumed. The LHCC encourages the ATLAS Collaboration to continue their studies on heavy ion physics with a view to submitting a Physics Performance Report.

The next ATLAS Comprehensive Review will be held on 28-29 June 2004.
 

4. REPORT FROM THE CMS REFEREES

The LHCC heard a report from the CMS referees, concentrating on the general progress and the status of the Tracker, ECAL, HCAL, and Muon System projects and a report on the electronics, trigger and data acquisition systems.

The LHCC heard a report on the Tracker, comprising the Pixel and Silicon Tracker detectors. Good progress was reported on the module assembly of the Silicon Tracker at all production centres while the problem of the hybrid electronics via related to the marginal deposition of the Cu line has been resolved by optimizing the laser beam settings and improving the quality assurance procedures. The Committee took note that CMS plans to make a final decision on the Silicon Tracker sensor production at ST Microelectronics and Hamamatsu by the end of July 2004. The Committee endorses the CMS plan but expressed deep concern about the overall schedule. Good progress was reported on mechanical components of the Silicon Tracker assembly and on the read-out electronics. No major concern was reported on the Pixel detector.

The Committee also heard a report on the ECAL. The interim agreement with the Russian supplier for the production of crystals is considered to be a positive step. Enormous efforts are underway to ensure complete production of the EB and EE crystals in time and to consolidate the required finances. Assembly of the Supermodules is under control and the support structures have been made for the first EE Dee. Very good progress was reported on the electronics. Chips from the engineering run are in hand and are being tested and the final production is scheduled to be launched soon.

Good progress was reported on the HCAL. The HB, HE and HO detectors are ready to be cabled and commissioned on the surface prior to being lowered and production of the front-end electronics is underway. Assembly of the HF detector is advancing. Calibration of the HCAL will be finalised in test beam in 2004 using particle beams in the energy range 3 to 300 GeV.

The referees also reported on the Muon System. Production of the DT chambers is advancing but the Committee expressed concern on the schedule for the production of the MB4 chambers at Torino, the new HV board and the Minicrate electronics. Significant progress was reported on the CSCs and on the RPCs.

The LHCC also heard a report on the CMS read-out electronics, and the Trigger and Data Acquisition System. The Committee noted the good progress in all these areas.

The referees also reviewed the general status of the experiment. Good progress was reported on the construction of the magnet coil modules and negotiations for the heavy lowering tender are advancing. Civil engineering for the underground caverns is progressing. The LHCC took note of the new CMS Master Schedule V34 and will use it henceforth to monitor the progress of the experiment.
 

5. REPORT FROM THE ALICE REFEREES

The LHCC heard a report from the ALICE referees, concentrating on the general status of the detector construction and on a report on the ALICE Trigger, Data Acquisition, High Level Trigger and Control System Technical Design Report.

Good progress was reported on the construction of the ALICE sub-detectors. Production of the ITS, the TPC, the TRD, the TOF and the Dimuon Spectrometer are advancing well. The Committee did, however, note the low yield for the TOF ASIC read-out chip. ALICE is investigating the problem and will report to the next meeting of the LHCC.

The Committee also heard a report on the Forward Detectors. Good progress was reported on the design of the detectors since the ALICE Comprehensive Review in March 2004. The ALICE management is actively involved in resolving the remaining design issues and several decisions are expected to be taken within the next few months. Submission of a common Forward Detector Technical Design Report is expected for the autumn 2004.

The LHCC also heard a report on the Trigger, Data Acquisition, High Level Trigger and Control System Technical Design Report. Given that the experiment has been designed primarily to run with heavy-ion beams, the requirements on the lower level trigger selectivity are considered to be modest compared to the other LHC experiments, whereas the trigger complexity is considerable and requires partial or full event reconstruction in the high-level trigger. In addition, a large bandwidth DAQ together with efficient data selection and/or data compression in the High Level Trigger are required to collect sufficient statistics in the short running time available to ALICE. In proton-proton or proton-ion running mode, the requirements on the trigger selectivity are increased and those for the trigger complexity and bandwidth are much reduced. The Control System, consisting of the Detector Control System which has the aim of ensuring the safe and correct operation of the ALICE experiment and the Experiment Control System which is to provide a unified view of the experiment and a central point from where all operations are initiated and controlled, is also described.
 

6. ALICE TRIGGER, DATA ACQUISITION, HIGH LEVEL TRIGGER AND CONTROL SYSTEM TECHNICAL DESIGN REPORT

The LHCC has completed its scientific and technical evaluation of the ALICE Trigger, Data Acquisition, High Level Trigger and Control System Technical Design Report submitted in January 2004. The Committee congratulates the ALICE Collaboration for the work presented in the Technical Design Report. The solutions adopted for the various systems are adequate to run the experiment and to achieve the physics goals stated in the ALICE Technical Proposal.

The Committee has no major concerns. An ancillary document (LHCC 2004-018 / G-076) 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 ALICE follows the established process of conducting independent reviews of the engineering designs. Written reports should be made available to the LHCC through its referees.

Recommendation

The LHCC recommends general approval of the ALICE Trigger, Data Acquisition, High Level Trigger and Control System Technical Design Report pending a final cost evaluation. The LHCC considers the schedule given in the Technical Design Report 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. REPORT FROM THE LHCb REFEREES

The LHCC heard a report from the LHCb referees, concentrating on the general status of the experiment and a report on the detector electronics.

Good progress was reported on the assembly of the dipole magnet, the experimental beam pipe, the VELO, the Inner and Trigger Trackers and the Calorimeters. Development of the RICH-1 is advancing according to the LHCC milestones. Its schedule, however, remains very tight and is limited by the available manpower. The LHCC urges LHCb to resolve the current areas of concern. The Committee noted with concern that the production of the Outer Tracker has not yet taken-off and a delay of 4 months with respect to the LHCb schedule was reported. The Committee urges the Outer Tracker group together with the LHCb management to study ways to recover the delay. In addition, the LHCC noted that the MWPC detectors for the Muon System have not yet reached stable production at all centres and the overall fabrication of chambers is late by about 5 months. The Muon System group and LHCb management is urged to take action to avoid further delays. The LHCC noted that the Data Challenge 2004 is underway and will provide a test of the computing model for the LHC.

The referees also reported on the status of the LHCb electronics. The referees reported on radiation hardness issues for the electronics, their installation in the LHCb experiment, common solutions across several systems, and the status of electronics for the VELO, Calorimeter, Outer Tracker and Muon System. The LHCC took note of the good progress in all these areas and noted the plans for the future which include full chain tests with the final read-out systems, the definition and test of the final (common) LV power systems, and the series production, testing and qualification of the final electronics.
 

8. REPORT FROM THE TOTEM REFEREE

The LHCC heard a report from the TOTEM referee, concentrating on pending issues from the previous meeting of the Committee.

TOTEM has demonstrated very good progress in several areas since the previous meeting of the LHCC. Tests on a prototype Triple GEM detector for the T2 Telescope show that no damage to the detector is expected from the sparking frequency coming from the particle production densities and that the detector is expected to be insensitive to ageing during long-term operation. Preparations for the upcoming test in the SPS Ring are advancing well. Two Roman Pots are available for the test and the infrastructure and technical services are being installed. Three types of detectors for the Roman Pots are under evaluation — planar detectors with two guard rings, planar 3D detectors with an active edge and pure 3D detectors. Good progress was also reported on the read-out electronics for the Roman Pot detectors. The LHCC also took note of the revised cost estimate for the experiment. A full report on the cost estimate is being prepared by CORE.

The Committee requested additional information on the financial and manpower share of the individual collaboration institutes and noted that the arrangement of details with the CMS needs further discussions.

The LHCC will again review the TOTEM Technical Design Report and the Addendum to the Technical Design Report, which will provide details on pending issues from the previous meeting of the Committee, prior to presenting its recommendation.
 

9. REPORT FROM THE LHCf REFEREES

The LHCC heard a report from the LHCf referees on the Letter of Intent to measure photons and neutral pions in the very forward region of the LHC (LHCC 2003-057 / I-012 Rev. 2). The aim of the experiment is to provide knowledge of the energy distribution of particles in the very forward region for the understanding of cosmic ray phenomena. The Collaboration proposes to install a scintillating fiber imaging calorimeter at a forward location about 140 m from an LHC interaction point, the choice of which has not been made. The referees find the physics goals of the experiment sound and endorse the scientific value of the proposed measurement.

The LHCC encourages the LHCf Collaboration to continue the development of their experimental design with a view to submitting a Technical Design Report by the end of 2004. Future studies should include the measurement of the energy resolution of the calorimeter in test beams in order to validate the Monte Carlo simulations, a full evaluation of the radiation hardness of the detector, and a decision on the location of the detector and resolution of any conflicts with other detectors for the experiments and machine at this location.
 

10. REPORT FROM THE LCG REFEREES

The LHCC heard a report from the LCG referees, concentrating on progress since the last meeting of the LHCC and on the status of the Computing Memoranda of Understanding (MoUs).

Significant progress was reported in many areas. More than 40 Regional Centres, comprised of more than 3100 CPUs, are connected to the LCG, and with several in the process of being connected. The Data Challenges 2004 are in progress across all experiments and a report, emphasizing what has been learned with respect to the LCG Project, will be given to the LHCC referees in September 2004. Good progress was also reported on Phase II of the LCG Project. In particular, development of the applications area, automation of the fabric management, delivery of middleware, deployment of the Grid and feedback from the first Data Challenges are providing the first steps in establishing the base computing model, capacity and service requirements. The LHCC noted that further work needs to be done to better integrate the data management of the key regional centres in the direction of the Grid deployment area, to define a programme of Service Challenges and to resolve the shortage of LCG staffing for the common activities at CERN.

A Task Force for the Computing MoUs has been set up with the aim of drafting an LCG MoU and one MoU for each of the four major LHC experiments. First drafts of the MoUs are expected for the autumn 2004.

11. TEST BEAMS

The SPS and PS Physics Coordinator gave a report on the LHC test beams.

He reported on the problems with water pipe connections at the PS Booster. They have been found to be leaky and all connections had to be re-done prior to proceeding with the start-up of the PS Complex. This has resulted in a one-week delay to the start of physics for 2004 at both the PS East Hall and at the SPS and a revised schedule is being prepared.

The SPS and PS Coordinator also reported on recent requests for beam time. Requests have been submitted for a two-month neutron irradiation run in the PS East Hall, from COMPASS for an extension to the SPS run by one week in November 2004 as compensation for the delay in the SPS start-up, and from NA60 for one week with the SPS running at the lower proton momentum of 158 GeV/c. These requests will be prepared and presented for a decision to the next LHCC.

The LHCC took note of the paper from CMS outlining the physics motivations for test beams in 2006 for the Electromagnetic Calorimeter.
 

12. DATES FOR LHCC MEETINGS

                     Dates for 2004: 30 June - 1 July
29-30 September
24-25 November
 
The LHCC received the following documents:
                  - Physics motivations for the request of test beams in 2006 for the CMS electromagnetic calorimeter
                    (LHCC 2004-017/G75)*

                  - Review of the ALICE Trigger, Data Acquisition, High-Level Trigger and Control System TDR (LHCC 2004-018/G76)*

* restricted circulation                                                                                        Emmanuel Tsesmelis
                                                                                        E—mail: LHCC.Secretary@CERN.CH
                                                                                        Tel. 78949, 164057

LHCC Secretariat: Janet Grant (Bldg. 14/4-022) Tel. 73424

                 janet.grant@CERN.CH