CERN/LHCC 93-60

LHCC 8

25 November, 1993

LARGE HADRON COLLIDER COMMITTEE

Minutes of the eighth meeting held on Tuesday and Wednesday, 16-17 November 1993

OPEN SESSION :

1. Presentation of LHB Letter of Intent (LHCC 93-45 / I 5; G.Carboni).

2. Presentation of COBEX Letter of Intent (LHCC 93-50 / I 6 rev.1; P.Schlein).

3. Presentation of GAJET Letter of Intent (LHCC 93-54 / I 7, LHCC 93-58 / I 7 corr.; T.Nakada).

CLOSED SESSION :

Present: J.V.Allaby, J.J.Aubert (Chairman), G.Brianti (for point 6), R.J.Cashmore, L.Di Lella, P.J.Dornan, P.Duinker, K.Einsweiler, F.Eisele, J.Ellis, E.Fernandez**, L.Foa, W.Hoogland, E.Iarocci, P.G.Innocenti, K.Kajantie, V.Khovansky**, C.Llewellyn Smith (for point 1), G.W.London, G.Mikenberg**, K.Potter, K.Pretzl**, K.Schubert, D.M.Sendall (Secretary), M.Turala**, D.O.Williams, S.Yamada

**) Absent for point 8

Apologies: C.Rubbia

(P.Darriulat was present for point 2, F.Brasse for point 4, F.Dydak and P.Jenni for point 7, M.DellaNegra, T.Meyer, E.Radermacher and T.Virdee for point 9).

1. The minutes of the seventh LHCC meeting (LHCC 93-37 / LHCC 7) were approved without amendment.

The Chairman welcomed M.Turala, who replaces E.Iarocci as Chairman of the DRDC. The Chairman announced the resignation of L.Maiani, and expressed appreciation for his work with the LHCC. E.Iarocci had been appointed in his place.

The Chairman announced some changes in the referees, and thanked the retiring referees for their work. The referees are now as follows:

ATLAS: P.J.Dornan, P.Duinker, F.Eisele (Coordinator), S.Yamada.

CMS: R.Cashmore (coordinator), K.Einsweiler, E.Iarocci, K.Schubert

C.Llewellyn Smith made a brief statement on the implications of the recent decision on the SSC.

2. RHIC EXPERIMENTAL PROGRAMME

P.Darriulat summarised the scope and parameters of the RHIC project, and the likely construction and funding profile. He outlined the main characteristics of PHENIX and STAR and the two smaller experiments BRAHMS and PHOBOS. The possibility of using RHIC for kinds of physics other than heavy ion physics was mentioned.

3. REFEREES` REPORT ON B PHYSICS LETTERS OF INTENT

P.J.Dornan, J.Ellis and E.Fernandez reported on the work of the B physics referees. They summarised the interest of B physics at the LHC both within and beyond the Standard Model. In addition to a preliminary review of the three Letters of Intent, the referees had also had discussions with ATLAS and CMS, and with accelerator experts. The potential of specialised B experiments was compared with that of the general-purpose experiments. It is clear that the vertex detectors and particle identification are crucial components of the specialised experiments. Many figures presented are preliminary, and more work remains to be done on various aspects of the Letters of Intent. Following discussion it was agreed that the referees would draw up a list of questions raised, and try to get a uniform response from the three collaborations for presentation at a future meeting of the LHCC.

4. COSTS REVIEW GROUP

F.Brasse gave a status report on the work of the CORE group. He presented the second report of the group (LHCC 93-44) on ALICE. CORE feels that the Collaboration has already made reasonable preliminary estimates in most areas. More work is needed on particle identification and on detailed layout. Some costs can be realistically evaluated only when a choice of magnet and intersection region is made. Data flow and mass storage remains an area of concern, although some progress has been made in reducing the mass storage requirements.

CORE has had further discussions with the ATLAS and CMS Collaborations. Good progress has been made on detector R&D and costing. Baseline options are now better defined, and updated cost estimates were reported. There is now no substantial disagreement between the Collaborations` figures and the CORE estimates. Some areas of concern include R&D costs, testing, failures and spares. These should be followed in parallel with the preparation of Technical Proposals

5. ALICE REFEREES` REPORT

G.London reported on the work of the ALICE referees, indicating what could be expected for ion physics at LHC compared with RHIC. The Collaboration had given detailed answers to the list of questions put to them. The referees had looked at the overall experimental approach, the question of angular acceptance, the main tracker, particle identification, and the photon spectrometer (PHOS). The question of the interaction region was also considered.

K.Potter commented on the possibility and potential problems of low luminosity pp operation.

After discussion, the committee agreed on recommendations to be sent to the Director General for consideration by the Research Board. A copy of these recommendations is attached to the minutes.

6. STATUS OF THE LHC PROJECT

G. Brianti outlined the current status of the machine project. He summarised the main differences between the latest design and the "Pink Book" design study (CERN 91-03). The main machine parameters were reviewed, along with goals for the first year of commissioning. A possible approach to optimising luminosity in the startup period was described. A summary of cost estimates was presented. Recent ideas on alternative beam crossing schemes were also discussed.

7. ATLAS PROGRESS REPORT

F. Dydak and P. Jenni presented the progress report on ATLAS milestones (LHCC 93-51). They described progress on the inner tracker design, the baseline choices for calorimetry, the change to an 8-coil air-core toroid of reduced radius, and work in progress on layout of the forward region and the muon chamber system. The mechanisms and timescales for further decisions were explained. Possible layouts of the experimental area were shown. A preliminary estimate of available resources was also presented, and some changes in collaborating institutes were announced.

8. ATLAS REFEREES` REPORT

F.Eisele presented the views of the ATLAS referees on the report.

9. CMS PROGRESS REPORT

M.Della Negra presented the CMS status report and milestones (LHCC 93-48). He described the new layout for central tracking, with mechanical structure and cabling and figures for radiation length, as well as alignment and progress in MSGC work. The status of the shashlik calorimeter was presented: DRDC proposal P50 had been submitted in August. Prospects for other ECAL media were also discussed. The various muon chamber options and milestones and alignment procedures were described. The status of the magnet design was summarised and possible experimental area layouts given. Current estimates of costs, funding, and participation were given.

10. CMS REFEREES` REPORT

L. Foa presented the views of the CMS referees on the report.

11. DISCUSSION

The Committee discussed the progress reports of ATLAS and CMS and the referees` comments. The LHCC took note of the progress made, and agreed on recommendations to be sent to the Director General for consideration by the Research Board. A copy of these recommendations is attached to the minutes.

The Committee took note of the documents received on other physics topics

12. DATES FOR 1994 MEETINGS

The following dates were agreed:

27-28 January

6-7 April

7-8 June

30-31 August

9-10 November

The LHCC received the following documents:

LHB Collaboration: Letter of Intent: Measurement of CP violation in B meson decays with an extracted LHC beam (LHCC93-45/I5)

TOTEM Collaboration: Total cross section, elastic scattering and diffraction dissociation at LHC (LHCC 93-47)

CMS Collaboration: CMS Status Report and Milestones (LHCC 93-48)

CMS Collaboration: B physics and CP violation studies in CMS (LHCC 93-49)

COBEX Collaboration: Letter of Intent for a collider beauty experiment at the LHC at CERN (LHCC93-50/I6 rev.1)

ATLAS Collaboration: Progress report on ATLAS milestones (LHCC 93-51)

ATLAS Collaboration: B Physics with the ATLAS experiment at LHC (LHCC 93-53)

GAJET Collaboration: Letter of Intent: Study of CP violation in B-meson decays using an internal gas jet target at LHC (LHCC93-54/I7)

J.Panman and K.Winter: Memorandum concerning a Letter of Intent for neutrino physics at the LHC (LHCC93-55)

NOMAD Collaboration: Memorandum from the NOMAD Collaboration (LHCC 93-56)

L.Dick: Letter concerning "Physics with a jet target at LHC" (LHCC 93-57)

GAJET Collaboration: Errata to the Letter of Intent: LHCC 93-54/I7 (LHCC 93-58 / I7 corr.)