CERN/LHCC 2003-024
LHCC 64
27 May 2003

 
LARGE HADRON COLLIDER COMMITTEE

Minutes of the sixty-forth meeting held on
Wednesday and Thursday, 21-22 May 2003



 
 
 
 
 

OPEN SESSION:             1.    Report from the Workshop on Hard Probes in Heavy Ion Collisions at the LHC : Urs Wiedemann

             2.    Report from the 4th International Symposium on LHC Physics and Detectors: Kerstin Hoepfner

             3.    ATLAS Test Beam Programme : Beniamino Di Girolamo

             4.     CMS Test Beam Programme: Emmanuel Tsesmelis
 

CLOSED SESSION:

Present:     K. Borras, M. Calvetti (Chairman), R. Cashmore, A. Ceccucci, J. Dainton, F. Ferroni,
                 M. Hauschild, M. Jaffre, Y.-K. Kim, J. Knobloch, H.Hoffmann*, M. Mangano, J. Martin,
                 P. McBride, J. Panman, J. Patrick*, K. Potter*, L. Robertson*, P. Seyboth, H. Tiecke,
                 K. Tokushuku, E. Tsesmelis (Secretary), C. Vallée, I. Videau*, V. Vuillemin (representing D. Schlatter),
                 T. Wenaus*

Apologies: S. Bertolucci, J.-J. Gomez Cadenas, Y. Karyotakis

                                                                                                        *) Part time

      1. PROCEDURE
    The minutes of the sixty-third LHCC meeting (LHCC 2003-018 / LHCC 63) were approved without modification.

    The report from the ALICE Comprehensive Review (LHCC 2003-019 / LHCC-G-036 Rev.) was approved without modification.
     

      2. INTRODUCTION
    The Director for Collider Programmes informed the LHCC on various issues concerning CERN in general and the LHC Project in particular.

    CERNís Medium Term Plan includes provision of funds for the consolidation and renovation of the PS and SPS machines particularly in view of their future use as injectors to the LHC. With the termination at the end of 2003 of the NA48/2 and DIRAC experiments, as well as the SPS heavy-ion programme, the SPSC, in parallel with international workshops, will begin looking at proposals for new physics experiments at the PS and SPS. Furthermore, the Medium Term Plan also includes funds for supporting accelerator R&D at CERN focused on CLIC.

    The upcoming CERN Council sessions will include a presentation for approval of the Local Staff proposal and the new Director-Generalís plan for the future organizational structure of CERN.

    The Resource Review Boards (RRBs) met in April. Additional funds towards the ATLAS and ALICE cost-to-completion were reported while funds for the 2003 M&O are becoming available. With the aim of the experiments meeting their technical timetable, another round of cost analysis will be made for the October RRBs. The Computing RRB noted that funds have been provided for the LCG for 2003 and will start working towards securing the required funds for the following years. The Computing RRB will also start discussing the transition of the LCG from its present prototyping phase to the final installation for the LHC.

    The Committee took note of the upcoming LHCC review of the required and available manpower for the core and sub-detector software in the experiments and its relation to the LHC Grid Project (LCG). The review will be held during the first week of September 2003.

    The LHCC also discussed the Open Session. The Committee appreciates the work that has been done in the recent workshop on hard probes in heavy-ion collisions and thanked the speaker for the summary presentation. It considers that heavy-ion physics is a very important component of the LHC programme and encourages workshops on the subject to continue. The LHCC also thanked the speakers for the presentations on the 4th International Symposium on LHC Physics and Detectors and on the ATLAS and CMS test beam programmes. The LHCC will continue examining progress in testbeam activities of the LHC experiments and will cover this area in future Comprehensive Reviews.
     

       3.REPORT FROM THE ALICE REFEREES
    The LHCC heard a report from the ALICE referees, consisting of reviews on several of the sub-systems, the schedule and milestones, and comments from the technical coordination.

    The referees reported on the status of the ITS. The SPD is on track for a timely completion. In order to solve problems associated with inhomogenieties, a new supplier for the SDD sensor raw material has been identified and preparation of the certification test is in progress. The yield of the SSD HAL25 electronics is still under evaluation and will continue to be monitored by the Committee.

    The LHCC expressed concern at recent developments in the TPC project. A major 6-month delay was reported arising from the need to reconstruct the inner field cage of the detector. In addition, delays in the chamber and electronics production were reported. In view of these difficulties, the current planning now has a much-reduced commissioning period of the detector in ALICE. The LHCC requests a detailed report by ALICE on the status of the TPC project at the Committeeís next session.

    Good progress was reported on the Dimuon Forward Spectrometer, HMPID, TOF, ZDC, Trigger and DAQ. The Committee still awaits submission of the Addendum to the PMD Technical Design Report. The Committee also took note of the progress in the TRD. The delay in the production of the PASA front-end electronics will be absorbed in the time allocated for their production.

    The LHCC also heard a report on the ALICE High Level Trigger (HLT). The Committee acknowledges the efforts made by ALICE to take into account the recommendations of the external review committee and encourages the collaboration to proceed towards taking the necessary decisions as fast as possible. The LHCC requests that a report on the final decisions should be given at the July meeting of the Committee. Moreover, the LHCC reiterated its concerns regarding interface and integration issues of the DAQ and HLT identified at the recent ALICE Comprehensive Review and recommended again that submission of a common Trigger, HLT and DAQ TDR should not be delayed beyond the end of 2003.
     
     

      4. REPORT FROM THE ATLAS REFEREES
    The LHCC heard a report from the ATLAS referees, concentrating on a general progress report of the sub-systems, the schedules and milestones and items of concern.

    Good progress was reported on the installation of the technical infrastructure in the underground caverns at Point 1. Good progress was also reported for the LAr electromagnetic calorimeter, with the first half-barrel having been inserted and the second half-barrel being well into the stacking phase. Pre-assembly of the Tile Calorimeter is progressing well with the work advancing faster than planned. Good progress was reported on the SCT barrel and end-cap modules. Although thermal shields for the Barrel Toroid are now becoming available, there are still problems with the welding qualification, and the referees continue to express considerable concern on the overall Barrel Toroid schedule. The LHCC also noted that the delay in the delivery of the TRT web-circuit electronics is close to being critical for the Type-A production as the inner End-cap A is already late by 4 months.

    The referees also reported on the status of the DMILL production process. The firm ATMEL has announced that production in DMILL will be terminated in December 2003, with the last production orders to be taken in June 2003. Given that the 2002 production runs raised several worries due to the failure rate and low yield, the LHCC expressed its concern on the risk in procuring the total number of wafers, particular for the SCT ABCD, TRT ASDBLR and the chips for the LAr calorimeters, before the DMILL production is terminated. With the aid of the CERN Director for Collider Programmes, discussions are presently underway with ATMEL to achieve a viable solution. The impact on particularly the SCT and TRT schedule must be investigated and the ATLAS Electronics Coordinator has been asked to consider Deep Sub-Micron (DSM) alternatives.

    Good progress was reported on the RPC production. RPC production is advancing at the expected rate. The requested Quality Control document is now available and includes the results from the inspection of the non-functioning RPC chambers reported in March 2003. The faults have been traced back to the assembly of defective components and improper handling. Ageing tests at the GIF are continuing with the aim of accumulating a charge equivalent to 10 ATLAS years. Detection efficiencies are good while a modest increase of the current with source off is observed. The gas closed loop system has been mounted and will be introduced gradually into the tests.

    The referees also reported on the Higher-Level Trigger / DAQ. The final design review for the system was held in March 2003, at which point the choice of architecture was made. The Higher Level Trigger / DAQ TDR will be submitted to the LHCC at the end of June 2003.

    The LHCC noted that the majority of the milestones expiring in the period January ó May 2003 have been met. The milestones that were missed are considered not to be critical.

    The next ATLAS Comprehensive Review will be held on 30 June ó 1 July 2003.
     
     

      5. REPORT FROM THE CMS REFEREES The LHCC heard a report from the CMS referees, concentrating on a progress report on several of the sub-systems, an update on the schedule and milestones and a review of the Data Acquisition / High-Level Trigger (DAQ/HLT) Technical Design Report.

The LHCC took note of the water leaks in the two access shafts at Point 5. Their repair is estimated to be about 3 months and although there is contingency in the UXC55 cavern schedule with respect to the critical path, outfitting the USC55 service cavern is however critical as the time available to complete the installation is tight.

Production of the magnet coil is progressing well but is on the critical path. The estimated delay can be reduced from 4 to 2 months by speeding up production of the coil. The full current underground magnet tests may have to be sacrificed in order to compensate the above two-month delay in the magnet coil. However, the LHCC wish to emphasise that the functional tests, cooldown, electrical checks and leak tests on the cold magnet, must be preserved.

The referees reported on the status of the ECAL. Delivery of the crystals is now on the critical path and an increase in the production capacity by making 4 crystals per boule is now deemed necessary. The crystals for the End-cap must be ordered by the end of 2003. Production of bare supermodules is underway with the aim of completing 12 by the end of 2003. Given these developments, the LHCC requests a revised, cumulative production plot. Development of the modified architecture for the electronics is progressing. A crucial test programme and a decision of the Very Front-End (VFE) electronics are planned for this summer.

The LHCC also heard a report on the Tracker. Good progress was shown for the mechanics and system tests for the Silicon Strip Tracker (SST). The first production batch of sensors from Hamamatsu is of excellent quality except that the sensors are of higher resistivity than specified. The issue is being investigated and may be due to a misunderstanding in measuring the resistivity. The sensors from ST still exhibit quality control problems and the ramp-up in the production rate has paused while investigating the problems. Moreover, although production of modules is in progress, damage to bonds during shipment was reported and the causes need to be investigated. A 5-month delay to the SST was reported, meaning that the 3-month contingency allocated in the production and assembly schedule has now been used up. The referees also reviewed the status of the Pixel Tracker. No major concerns were identified but the Committee did note that translation of the read-out chip to 0.25 m m technology is in its final stages but only after a 3-month delay.

The referees also reported on the Muon System. Good progress was reported on the DT Superlayer production rate as well as equipping chambers at the ISR. The first MINICRATE front-end electronics unit is being tested in beam. A sound plan for the availability of RPCs and the combined DT and RPC installation in CMS was presented. It was also noted that the MB4 production line at Torino is now on the critical path. Good progress was also reported on the RPC production scheme and ageing test programme. Successful completion of the latter is considered by the LHCC to be essential. Furthermore, gap production for the Forward RPCs is ready to start in Korea. Finally, the Committee noted the excellent progress of the CSCs with all agreed milestones having been met.

Good progress was reported on the HCAL. Construction of the HCAL is mostly complete and the commissioning and exploitation phase is imminent. Although improving, the referees did note the concerns regarding the low HPD yield. The Committee will continue monitoring progress.

The LHCC also took note of the plans for the CMS Forward Region and for the electronics installation. The Committee also noted the milestones due until May 2003 and considers that the pressures on the schedules need to be carefully monitored in the future by the Committee.

The Committee heard a report on the CMS DAQ/HLT Technical Design Report. The functionality of the CMS DAQ/HLT system is three-fold: a) perform the read-out of the front-end electronics after a Level-1 Trigger accept, b) execute physics selection algorithms on the events read out in order to accept the ones with the most interesting physics content and c) forward these accepted events, as well as a small number of rejected events, to the online services which monitor the performance of the CMS detector and also provide a means of archiving the events in mass storage. In addition, the DAQ has the important functionality of operating the Detector Control System (DCS) for the operation and supervision of all detector components and the general infrastructure of the experiment.
 

      6. CMS DATA ACQUISITION AND HIGH-LEVEL TRIGGER TECHNICAL DESIGN REPORT The LHCC has completed its scientific, technical, and cost evaluation of the CMS DAQ and High-Level Trigger (HLT) Technical Design Report which was submitted in December 2002. The Committee was impressed by the quality of the work presented in the TDR and congratulates the Collaboration. The extensive R&D described in the TDR validates the concept of a single, staged HLT that handles all events accepted by the hardware trigger, without a physically independent "Level 2" trigger. Great advantage is taken of continual advancements in commercial technology to provide a very flexible and scalable system architecture.

The Committee has no major concerns. An ancillary document (LHCC 2003-025 / G039) records the overall assessment by the LHCC of the project at this time, thereby emphasising some points that should be monitored in the future as the project progresses. This document also contains a list of agreed milestones for monitoring the progress of the project. The LHCC review of the TDR was not a detailed review of engineering or procurement readiness. These are anticipated in the appropriate CMS procedures which are in place and which are used by CMS to monitor project progress (for example Procurement Readiness Review PRR and the Electronics Systems Review ESR). Written reports of PRR, ESR and other CMS reviews of the project should be made available to the LHCC through its referees.

Recommendation:

The LHCC recommends general approval of the CMS DAQ and High-Level Trigger Technical Design Report. The LHCC considers the schedule given in the TDR and the list of milestones in the ancillary document to be appropriate. 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 a review of the sub-systems, the schedule and milestones and progress towards the LHCb Detector Re-optimisation and Trigger Technical Design Reports.

Good progress was reported on the VELO, TT, Outer Tracker, RICH-2, the calorimeters and the muon system. The Committee also took note of the status of the experimental area and the LHCb test beam activities for 2003 and the good correlation between planned and achieved milestones. Work towards the LHCb Detector Re-optimisation and Trigger Technical Design Reports is in progress and the two reports will be submitted to the LHCC in September 2003 as agreed.

The referees reported on the status of the photodetector for the RICH. The LHCC remains very much concerned with the development of this photodetector and noted the various technical problems causing delays in the development of the HPDs and that the MaPMT option is now on the critical path because of a lack of resources attributed to the project. The Committee reiterated that focused studies of the HPD and MaPMT should continue with the aim of providing a final choice between the two options to be taken in September 2003.
 
 

      8. REPORT FROM THE APPLICATION SOFTWARE AREA OF THE LHC COMPUTING GRID PROJECT T. Wenaus presented a status report on the Application Software Area of the LHC Computing Grid Project (LCG), concentrating on the following issues: organization and overview of the effort, implementation of the architecture blueprint, available human resources, the schedule and milestones, external participation and collaboration and brief project status reports on POOL (the Persistency Framework), SEAL (Core Tools and Services), PI (Physicist Interface), Simulation and SPI (Software Process and Infrastructure).

The level of manpower appropriated to the application software area is considered adequate. It is at the level the experiments have estimated to be required, is being used effectively and efficiently for all the LHC experiments and is delivering on its mandate.

However, it was noted that GRID-related work has not yet been integrated into the applications area thus remaining an issue for further development. The September LHCC Computing Review, while primarily to be held to review resources in the core and sub-detector software in the LHC experiments, nonetheless offers an opportunity to put developments in the application software area in context with the GRID.

The LHCC congratulates the project management, together with EP and IT Divisions, on putting together successfully this group and considers that the approach and plan for the future are good.
 

      9. TEST BEAMS The SPS and PS Coordinator reported on the test beams.

He reported on the status of the PS and SPS accelerators. The 2003 start-up has been affected by equipment faults in the PS Complex (main bending magnets and transformer of the PS East Hall extraction septum) and in the SPS (main compensator). A major effort was made to minimize losses in beam-time but some delays to the physics programme and some re-scheduling was unavoidable. In order to compensate the losses at start-up, an extension of running the PS and SPS machines into November 2003 is being considered. The experiments are invited to submit justification and requests for the possible extension to the 2003 machine running period. Moreover, a working group has been created to plan for major renovations to these machines during 2005 in view of their future use as injectors to the LHC.

Finally, the SPS and PS Coordinator reported that the Research Board rejected all requests by the heavy-ion experiments, except NA60, for beam-time during the 2003 SPS Indium run. Beam-time for LHC test beams of CMS ECAL and ALICE has been allocated during the SPS heavy-ion run.
 

    10. DATES FOR LHCC MEETINGS Dates for 2003:                        2-3 July

                        24-25 September

                        26-27 November
 

       The LHCC received the following documents

                                                                        * restricted circulation  
 
 

                                                                        Emmanuel Tsesmelis
                                                                        Eómail: LHCC.Secretary@CERN.CH
                                                                        Tel. 78949, 164057

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

                 janet.grant@CERN.CH