6 October 2004
LARGE HADRON COLLIDER COMMITTEE
1. Report from CDF and D0: Y-K. Kim
2. Report on the ATLAS Barrel Toroid Magnets: H.H.J. ten Kate
3. ALICE Forward Detectors Technical Design Report: J.J. Gaardhoje, W. Trzaska, J.Y. Grossiord
Computing Grid Project Status Report: M. Schulz
Present: S. Bertolucci, K. Borras, M. Calvetti (Chairman), A. Ceccucci, J. Engelen, L. Evans*, J. Feltesse, F. Ferroni, F. Forti, J. Haba, M. Hauschild, M. Jaffre, S. de Jong, Y. Karyotakis, V. Kekelidze, J. Knobloch, M. Mangano, J. Martin, P. McBride, C. Niebuhr, B. Peyaud, K. Potter, D. Schlatter, P. Seyboth, S. Smith, H. Tiecke, E. Tsesmelis (Secretary), T. Wyatt
*) Part time
Excused: C. Vallee
The minutes of the seventy-first LHCC meeting (LHCC 2004-024 / LHCC 71) were approved with two modifications. In point 5 (Report from the LHCb Referees), the fourth sentence of the third paragraph should be replaced by 'Production of MWPCs for the Muon Spectrometer is underway at four sites, but delays have been encountered due particularly to problems with machined or pre-assembled parts being outside the specification and to difficulties to start up the production line.' In point 6 (TOTEM Technical Design Report), the sentence 'The report from CORE (LHCC 2004-013 / G73) shows that the cost is considered to be reasonable and that a possible shortage of manpower is noted' should be inserted immediately after the second sentence of the fifth paragraph.
The report from the ATLAS Comprehensive Review (LHCC 2004-023 / G-079) was approved without modification.
The Chairman thanked the outgoing members A. Ceccucci, F. Ferroni, M. Jaffre, Y. Karyotakis, P. Seyboth, and H. Tiecke for their dedication and invaluable assistance provided as members of the LHCC.
The Chairman welcomed the new members F. Forti, J. Haba, S. de Jong, C. Niebuhr, and B. Peyaud to the Committee.
The Chief Scientific Officer expressed his gratitude to M. Calvetti for his excellent work as Chairman of the LHCC over the last three years. The assistance provided by him in this capacity both to the Organization and to the LHC community has been invaluable.
2. REPORT FROM THE CHIEF SCIENTIFIC OFFICER
The Chief Scientific Officer (CSO) reported on the status of the LHC Project. Following the delays in the installation of the LHC machine caused by difficulties in the QRL cryoline, the overall machine installation schedule remains under review. A revised LHC machine installation schedule will be released once the situation with the QRL cryoline has been fully evaluated. The aim is to collide beams in the LHC in the Summer 2007.
3. REPORT FROM THE ALICE REFEREES
The LHCC heard a report from the ALICE referees, concentrating on the general status of the detector construction, and the Forward Detectors Technical Design Report.
The Committee heard a report on the referees' preliminary reactions to the ALICE Forward Detectors Technical Design Report (LHCC 2004-025 / ALICE TDR 011). The Technical Design Report describes the Forward Detectors comprising the T0, V0 and Forward Multiplicity Detector (FMD) systems. The T0 detector consists of two arrays of PMTs equipped with Cherenkov radiators and will supply fast timing signals which will be used in the ALICE Level-0 trigger, provide a wake-up call for the TRD detector and deliver collision time reference signals for the TOF detector. The V0 system consists of two disks of segmented plastic scintillator tiles read out by optical fibres and will provide the online ALICE Level-0 centrality trigger by setting a threshold on the the deposited energy and will provide a background rejection capability for the Dimuon Forward Spectrometer. The FMD detector consists of 51 200 silicon strip channels and together with the Pixel system of the ITS, the FMD will provide charged particle multiplicity distributions for all collisions, allow the study of multiplicity fluctuations on an event by event basis and enable flow analysis. The Committee is currently reviewing the ALICE Forward Detectors Technical Design Report and following questions and discussions, the referees will make a full report at an upcoming meeting of the LHCC.
The LHCC took note of the detector construction status. Problems with the sensor wafers, the aluminium/polyimide pixel bus and the MCM electronics substrate have caused a 6-month delay to the production of the Silicon Pixel Detector (SPD). The plan is to have the half-stave assembly started at the end of October 2004. Sensor production for the Silicon Drift Detector (SDD) is progressing. SDD module production has not yet started but ALICE expects to meet its December 2004 milestone of 30 modules and to start ladder assembly in November 2004. The full production of all electronics components has been launched and will be available at the end of 2004. Production of sensors for the Silicon Strip Detectors (SSD) has been delayed at one producer while production of the modules is presently ramping-up and ladder production has not yet started.
The full production rate of the TRD chambers has not yet been achieved and the delay in the production is now 5 months. Start of production of the read-out electronics boards is delayed until all components can be exercised together and tested in beam in November 2004. A revised schedule is being prepared.
Good progress was reported on the construction of the HMPID, TPC, TOF, the muon dipole magnet and tracking chambers and the ZDC.
4. REPORT FROM THE ATLAS REFEREES
The LHCC heard a report from the ATLAS referees, concentrating on the general progress and the status of the detector construction.
The LHCC took note of the good progress in the ATLAS magnet system. The Committee congratulates ATLAS on the successful testing of the first Barrel Toroid (BT-1). BT-1 is scheduled to be installed in the ATLAS underground cavern in October 2004 with the last barrel toroid module scheduled for installation in June 2005. All 16 coils for both End-cap Toroids (ECTs) are wound and 12 of them have been impregnated. Assembly of the first ECT will be done in Hall 191, on schedule for completion in Spring 2005.
The cold system test for the Barrel LAr EM Calorimeter and the solenoid magnet in the common cryostat have been completed successfully in Hall 180 and the complete system is scheduled to be transported to the ATLAS underground cavern at the end of October 2004. Good progress was reported on the LAr End-caps and the Extended Barrel Tile Calorimeter has undergone a successful load test in Hall 185 for the subsequent assembly of the ATLAS calorimeter End-caps.
Good progress was reported on the Inner Detector, Pixel Detector, SCT, and TRT. During the past 3 years, the Inner Detector has faced several technical problems and although they have all been solved, the result of the past difficulties is that the schedule for the Inner Detector remains a concern, as there is no float left in the installation schedule.
Good progress was reported on the muon detectors. MDT production is progressing while that for the CSCs is complete. Production of TGCs is as scheduled and the RPC production is expected to be complete by Spring 2005 despite the delays generated by the late shipment of panels. The LHCC noted the progress on the ASIC read-out electronics for the RPC and TGC, which had recently shown difficulties in fabrication.
The LHCC took note of the new ATLAS Installation Schedule Version 6.24 which is a working version not yet baselined; the ongoing Combined Test Beam, which links all detectors of a slice through ATLAS with the Trigger/DAQ and Computing; the ATLAS Computing timeline; and the status of the infrastructure installation at Point 1 (ATLAS) of the LHC.
5. REPORT FROM THE LHCb REFEREES
The LHCC heard a report from the LHCb referees, concentrating on the general status of the experiment and the milestones.
Assembly of the dipole magnet is advancing and the first field measurements are scheduled for November 2004. Good progress was reported on the calorimeter production and preparations for its installation, on the RICH-1 and RICH-2 detectors, and the assembly of the Muon Filter is progressing as expected. Installation of the infrastructure and technical works in the underground experimental cavern are advancing well. Good communication was reported between LHCb and the LHC Machine for the installation of accelerator components in and through the UX85 experimental cavern. The LHCC, however, noted difficulties encountered in the construction of certain sub-detectors. Delays in the hybrids, modules and sensors for the VELO, the slow delivery of RICH HPD photon detectors, and the 6-month delays in the Outer Tracker module production and production of MWPCs for the Muon System are of particular concern. The LHCC will review in detail the progress in these areas at its next session. Moreover, the Committee asks LHCb to present a status report on the physics backgrounds expected at the LHC.
The LHCC also took note of the LHCb milestones.
6. REPORT FROM THE LCG REFEREES
The LHCC heard a report from the LCG referees, concentrating on lessons from the Data Challenges, progress in ARDA, gLite Middleware and Castor, LCG-2 and the review of the computing resource requirements.
The referees reported on the Data Challenges, and the LHCC noted the problems with the stability of operations at various sites and those regarding interactions with job scheduling systems. Further tests on the CASTOR data storage system are planned for the ALICE DAQ Challenge in November 2004 and the experiments request a more rapid release cycle so that they can test the prototypes.
Good progress was reported on ARDA - A Realisation of Distributed Analysis - is a project of the LCG whose main activitiy is to enable LHC analysis on the Grid. ARDA is successfully using the gLITE prototype being developed by the Enabling Grids for E-science in Europe (EGEE) project, and is preparing for larger scale demonstrations of the new Middleware capabilities. Problems with the distribution and packaging of Middleware for use at remote sites is expected to be resolved in the upcoming release scheduled for the end of 2004.
The LHCC took note that the outstanding issues for manpower and funding regarding LCG-2 are being addressed.
The Committee also discussed the upcoming review of the computing resource requirements - disks, tapes, CPUs and networks for Tier 0, Tier 1 and Tier 2 - of the experiments. Starting from the requirements documents, the task of this review is to examine critically, in close discussion with the computing managements of the experiments, the current estimates and report on their validity in the light of the presently understood characteristics of the LHC experimental programme. The review will be held in January 2005 and the experiments have been asked to submit their papers by the end of 2004.
The next LHCC Comprehensive Review of the LCG Project is scheduled for 22-23 November 2004.
7. TEST BEAMS
The SPS and PS Physics Coordinator gave a report on the status of CERN's accelerator complex and on the LHC test beams.
The Coordinator reported on the status of the PS Complex and the SPS. The spare septum magnet installed in May 2004 to replace a faulty septum magnet also failed after six weeks in use. As there was no further spare, it was decided to perform an emergency repair in three weeks of the septum magnet removed in May. During the repair period, the SPS continued to work but with lower intensity as the failed septum magnet continued to operate without cooling. Furthermore, a PS magnet in the irradiation beam line failed in August 2004 and irradiations in the PS East Hall were stopped for 7 days. Rescheduling of the programme had the most urgent irradiations performed immediately after the repair. Finally, various magnet cooling problems at the PS and SPS in early September resulted in loss of physics of a few days.
He also reported on the now approved extension to the SPS run in November 2004. The extension has been approved by the Research Board to compensate for the delays at the beginning of the 2004 SPS run. End of physics at the SPS, and at the PS East Hall, is now scheduled for 15 November.
The LHCC took note of the SPS and PS User Schedules and the requests for test beams in 2006.
8. STATUS OF THE LHC PROJECT
L. Evans reported on the status of the LHC Project. Delivery of components for the LHC machine is proceeding at a rate which is compatible with the start-up of the accelerator in the summer of 2007. Good progress was particularly reported on the TI8 transfer line, on the dipole magnets and the Short Straight Sections which incorporate the quadrupole magnets.
He also reported on the recent problems with the QRL cryogenic line. Cracked support tables were discovered during the disassembly of a module pipe bundle that had developed a vacuum leak due to bad welds. Subsequent endoscopic investigation revealed many other broken support tables. The support tables were found to be brittle and subject to breaking under shock due to the use of improper material. The correct material will now be procured and used for new support tables and the design of the support tables has also been improved. All tables produced so far will be scrapped. The action line follows three axes, ranked by order of priority:
-Restart the production of QRL modules with new support tables at Air Liquide plants.
-Restart the installation of the QRL, starting with Sector 8-1.
-Repair the already produced QRL modules equipped with bad support tables.
The QRL situation will have an impact on the installation and overall planning of LHC Project. The impact of these delays can only be evaluated reliably once the QRL installation is proceeding smoothly. In order to recover some of the delay, the sequence of QRL installation has been modified and local cabling is being done before the QRL installation. The LHC Project is committed to providing colliding beams in the LHC in the Summer 2007.
Since the fourth of the CMS Comprehensive Reviews in October 2003, the CMS Collaboration has made very significant progress towards the realisation of an experimental set-up ready for LHC operation in the Summer 2007.
It is realistic to expect CMS to install an initial working detector suitable for LHC operation starting in Summer 2007, although the completion of the detector installation can be foreseen beyond this date. The LHCC considers that the CMS schedule to achieve this is challenging. In particular, the Committee expressed its deep concern on the outstanding critical items related to the timely completion of the Electromagnetic Calorimeter (ECAL) and Silicon Strip Tracker (SST). Moreover, the schedule has no margin left in the 'Ready for Installation' milestones of the Drift Tube (DT) and Resistive Plate Chamber (RPC) detectors of the Muon Spectrometer and installation of the ECAL End-cap (EE) and Preshower (ES) detectors is now scheduled for the 2007/2008 winter shutdown period. The Pixel Detector, although expected to be ready for the LHC pilot run, will also be installed during the 2007/2008 winter shutdown period to minimize risk of damage during the initial stages of LHC operation. The LHCC noted that additional resources, both in terms of money and manpower, would aid in accelerating the current CMS schedule, and thereby would ensure a timely completion of the initial detector in 2007.
In the event that additional funding is not available to ensure completion of CMS in 2007 as described in the Technical Design Reports, the installation of some components of the Tracker, HCAL, Muon System, and TRIDAS will be deferred in a staging plan which has been prepared. The proposed staging plan for the experiment is aimed at having as small as possible an adverse impact on the Higgs and SUSY sensitivity at a luminosity of order 1033 cm-2 s-1. In these circumstances, the installation of staged components, in a shutdown after the completion of the low luminosity running, while requiring additional resources, would complete the CMS detector as described in the approved Technical Design Reports for high luminosity running.
The fifth annual LHCC Comprehensive Review of CMS took place on 27-28 September 2004. The LHCC referees addressed the following areas: Tracker, Electromagnetic and Hadronic Calorimetry, Muon Spectrometer, Trigger/DAQ, Computing/Software, and the topics of Management, Technical Coordination, Integration, Schedules and Costs.
The conclusions and concerns of the LHCC are given below. They will help the Committee to follow up outstanding issues and to monitor future progress of this project in forthcoming sessions of the LHCC prior to the next CMS Comprehensive Review one year hence.
Following changes to the LHCC membership, the new referee teams are as follows:
ALICE: J. Haba, C. Vallee (Co-ordinator)
ATLAS: F. Forti, V. Kekelidze (Co-ordinator), T. Wyatt
CMS: S. de Jong, J. Martin (Co-ordinator), P. McBride, S. Smith
LHCb: K. Borras (Co-ordinator), C. Niebuhr, B. Peyaud
TOTEM: K. Borras
RD42: V. Kekelidze
RD50: C. Vallee
LCG: F. Forti, P. McBride, T. Wyatt
11. DATES FOR LHCC MEETINGS
Dates for 2004:
Provisional Dates for 2005:
- Review of theTOTEM experiment (LHCC 2004-022/G78)*
- ALICE Technical Design Report of Forward Detectors, LHCC/2004FMD, T0 and V0 (LHCC 2004-025/TDR 11)
* restricted circulation
Tel. 78949, 164057
LHCC Secretariat: Janet Grant (Bldg. 14/4-022) Tel. 73424. firstname.lastname@example.org