CERN/LHCC 95-55

LHCC 19

2 October, 1995

LARGE HADRON COLLIDER COMMITTEE

Minutes of the nineteenth meeting held on Wednesday and Thursday,
13-14 September 1995

OPEN SESSION :

The Director General expressed both personally and on behalf of the community his gratitude to the retiring Chairman J. J. Aubert for the major role he had played during the first three years of the Committee's existence.

1. Status of the LHC project (C.Llewellyn Smith)

2. Status of the LHC machine (L.Evans)

3. Letter of Intent for LHC-B (LHCC 95-5/I 8; T.Nakada, P.Schlein)

CLOSED SESSION :

Present: J.J.Aubert (Chairman), J.Bernabeu, R.J.Cashmore*, L.DiLella, C.Dionisi, P.J.Dornan, P.Duinker, F.Eisele*, J.Ellis, L.R.Evans*, L.Foa, U.Goerlach, G.Goggi*, A.Golutvin*, J.Harvey* (representing M.Turala), H.J.Hilke* (representing G.Goggi), E.Iarocci, G.Kellner* (representing M.Turala), C.Llewellyn Smith*, H.Montgomery, K.Potter, A.Schopper, K.Schubert, D.M.Sendall (Secretary), H.Wenninger*, D.O.Williams, G.Wormser.

*) Part time

Apologies: P.Igo-Kemenes, K.Kajantie, S.Yamada

1. The minutes of the eighteenth LHCC meeting (LHCC 95-41 / LHCC 18) were approved without amendment.

2. L.Foa gave a summary of the expected resources of the ATLAS and CMS collaborations following his discussions with the funding bodies.

3. ATLAS status report

P.Jenni gave a report covering the composition of the collaboration, project milestones, distribution of responsibilities and procedures for taking decisions and commitments.

H.Hoffmann summarised the new cost estimates for the toroid system and the collaboration's plans for dealing with this.

4. CMS status report

M.DellaNegra gave a report covering the composition and organisation of the collaboration, status and milestones for the detector, costs, funding and schedules.

5. REPORTS FROM THE ATLAS AND CMS REFEREES

The committee heard reports by the ATLAS and CMS referees on their ongoing work in reviewing the technical proposals, and on the progress made by the collaborations.

6. REPORT FROM THE MAGNET ADVISORY GROUP

P.Lazeyras presented the report of the Magnet Advisory Group (LHCC 95-30), which is mainly a report on cost estimates. The situation of the ATLAS toroid system and work on the CMS conductor were summarised.

7. REPORT FROM THE LCRB ON ATLAS AND CMS COMPUTING

J.Harvey presented the LCRB report on the ATLAS and CMS technical proposals (LHCC 95-50). This covered the approach to trigger level 2 and above, data acquisition and general computing. The Trigger/DAQ strategy and planning of ATLAS and CMS were outlined. A technical proposal for computing is expected towards the end of 1996; the scope and topics to be addressed had been discussed with the collaborations.

8. DISCUSSION OF ATLAS AND CMS

The committee had extensive discussions of ATLAS and CMS. The LHCC is minded to recommend general approval of the ATLAS and CMS technical proposals at its November meeting. However, before doing so it will require more information on the collaboration's plans for dealing with cost variations and/or shortfalls in funding subsequent to the submissions of the technical proposals, including possible descoping and/or staging, and also better mutual understanding of technical milestones in future stages of approval.

9. REPORT FROM THE LDRB

On the R&D programme, status reports have been submitted by RD-34 and RD-42

Status Reports of approved projects presented at the open session

RD-34: Construction and Performance of an Iron-Scintillator Hadron Calorimeter with Longitudinal Tile Configuration (LHCC 95-44)

H.Tiecke gave an overview of the project, which had presented its last status report. The project has completed its generic R&D programme, and the LDRB congratulated the collaboration on the many results achieved in a short time. Further work will continue in the context of the ATLAS collaboration.

The LHCC agreed with these conclusions.

RD-42: Development of Diamond Tracking Detectors for High Luminosity Experiments at the LHC (LHCC 95-43, LHCC 95-53).

H.Tiecke gave an overview of the project and the results achieved so far. Substantial progress has been made on radiation hardness studies; an improvement of the charge collection distance is obtained in close collaboration with the detector producers, resulting in a better signal to noise ratio of their tracking (strip) detector. The LDRB has suggested milestones for a further year.

The LHCC took note. Before making recommendations, the LHCC requested the LDRB to discuss with the collaboration the possibility of working with pixels.

H.Tiecke also reported on presentations of development work on Resistive Plate Chambers by representatives of ATLAS and CMS. Joint activity is under way between ATLAS and CMS, and questions formulated by the LHCC are being addressed; discussions with the LDRB will continue. A framework is needed in which progress could be reported, and an open presentation to the LDRB could be foreseen. The LHCC encourages the LDRB to pursue these initiatives, and will discuss the matter further at a future meeting.

10. REPORT FROM THE LCRB

J.Harvey presented a report on the work of the LCRB. On the R&D programme, status reports have been submitted by RD-11, RD-13 and RD34, and a proposal received (P61).

Status Reports of approved projects presented at the open session

RD-11: Embedded Architectures for Second-level Triggering (EAST) (LHCC 95-45)

J.Harvey gave an overview of the project and reported on the conclusions of the LCRB.

Since its beginning in 1991, the RD11 project has made a major contribution to understanding the problems of triggering in p-p experiments at LHC. In particular systematic study of Level 2 algorithms and prototyping of Level 2 solutions was an important contribution to the ATLAS technical proposal.

The LCRB recognises that the goals of the original generic R&D programme in Second Level Triggering have been completed and that the project has come to an end. It is understood that the results will now be employed in specific developments for the experiments.

The LHCC agreed with these conclusions. The LCRB had also discussed the question of possible new High Performance Computing and Networking (HPCN) initiatives to investigate the use of Massively Parallel Processing (MPP) machines for implementing "farm" processing facilities. The LHCC considers that such work should not be carried out within the framework of RD11, which is considered to be at an end.

RD-13: A Scalable Data Taking System at a Test Beam for LHC (LHCC 95-47)

J.Harvey gave an overview of the project and its achievements so far, and reported on the conclusions of the LCRB.

The LCRB congratulates the RD13 team for the successful operation of the RD13 DAQ system in the ATLAS test beam. The LCRB believes that future responsibility for the support of test beam activities rests with the ATLAS collaboration.

The LCRB notes the large number of commercial software products that have been evaluated and used in the development of the RD13 DAQ system and recognises that this experience has been well documented in a comprehensive set of technical reports.

The LCRB agrees that the original objectives, as set out in the RD13 proposal, have been reached and that future developments should be conducted within the ATLAS collaboration. It therefore supports the intention of the RD13 collaboration to conclude the project.

The LHCC agreed with these conclusions.

RD-24: Application of the Scalable Coherent Interface to Data Acquisition at LHC (LHCC 95-42, LHCC 95-52)

J.Harvey gave an overview of the project and reported on the conclusions of the LCRB.

The LCRB noted the progress on development of data acquisition based on SCI by the RD24 collaboration. In particular, the milestones previously assigned by the DRDC have been met, resulting in a multi-node demonstrator of an SCI data acquisition system. It was noted that simulation results from RD24 led to the conclusion that a switching fabric is needed to make a scalable large size SCI data acquisition system. However, future large scale application of SCI will depend on the industrial availability of components and systems. Also, the switch fabric requirements are very likely to be detector specific. Therefore, the LCRB expects that any further work on SCI switches will be undertaken within the context of detector collaborations.

The LHCC agreed with these conclusions.

The LCRB noted the focus of RD24 on activities involving the widely accepted PCI bus, in particular for interfacing VME and computer systems.

Following the advice of the LCRB, the LHCC recommends the continuation of the project for a final year for this part of the work only, in order to consolidate the results obtained so far, with the milestone:

- Demonstrate an SCI based test data acquisition system, incorporating PCI-based computers and VME modules.

11. REPORT FROM THE LHC-B REFEREES

The committee heard a preliminary report from the LHC-B referees. The LHCC notes the substantial progress made by the collaboration as reflected in the Letter of Intent, and congratulates all those involved for their dedicated efforts. A number of questions remain to be discussed with the collaboration.

12. SUSY WORKSHOP

J.Ellis summarised the situation on supersymmetry studies. Although this could be one of the most important areas of LHC physics, detector simulations and projections of physics capabilities were not well advanced due to a number of practical problems. A possible plan of action would be for theorists to propose a limited number of parameter sets. In a second phase, experiments would study appropriate signatures and explore sensitivity in the neighbourhood of these points.

The LHCC considers this to be a promising approach, and proposes to hold a SUSY workshop at one of its open sessions, around one year from now.

13. OTHER BUSINESS

The committee took note of the paper on "Large" cross section p-p physics with a dedicated detector by Y.Takahashi et al. (LHCC 95-51)

The Chairman announced that he had received a memorandum from the Technical Inspection and Safety Division (TIS), which had held safety hearings on the ATLAS and CMS technical proposals. These did not reveal any problems which would at this stage prevent approval of the experiments. Further safety hearings will be held at later stages.

14. MEMBERSHIP OF THE LHCC

P.Duinker, F.Eisele, K.Kajantie, K.Schubert and S.Yamada are retiring from the Committee on 30 September. The Chairman expressed his warm appreciation for their contribution to the work of the LHCC. In the interests of continuity, the retiring members are invited to attend the 16-17 November meeting as full members.

The following new members have been appointed from 1 October:

J.Engelen, D.Hartill, N.McCubbin, M.Spiro, A.Schwarz.

15. DATES FOR 1995 MEETINGS

16-17 November

16. REVISED PROVISIONAL DATES FOR 1996 MEETINGS

Due to overlap with other meetings the schedule for 1996 has had to be revised.

1-2 February

28-29 March

30-31 May

4-5 July

29-30 August

31 October - 1 November

The LHCC received the following documents

o LHC-B collaboration: A Dedicated LHC Collider Beauty Experiment for Precision Measurements of CP-Violation (LHCC 95-5 / I 8)

o RD24 collaboration: LCRB Status Report (LHCC 95-42)

o RD42 collaboration: LDRB Status Report (LHCC 95-43)

o RD34 collaboration: LDRB Status Report (LHCC 95-44)

o RD11 collaboration: LCRB Status Report (LHCC 95-45)

o R&D proposal: "High energy physics processing using commodity components" (LHCC 95-46 / P61)

o RD13 collaboration: LCRB Status Report (LHCC 95-47)

o LCRB: Report on ATLAS and CMS technical proposals (LHCC 95-50)*

o Y.Takahashi et al.: 'Large' cross section p-p physics with a dedicated detector (LHCC 95-51)*

o RD24 collaboration: Addendum I to LCRB Status Report LHCC 95-42 (LHCC 95-52)

o RD42 collaboration: Addendum I to LDRB Status Report LHCC 95-43 (LHCC 95-53)

* Restricted circulation only.