EST-LEA/SW/99-7

LEMIC 37

23^rd November 1999

The minutes were accepted. B. Jeanneret announced that the collision scheme presented by Werner Herr is now documented in the LHC Project Note 315.

T. Watson recalled that the progress of the civil engineering work could be found at http://nicewww.cern.ch/st/ce/lhc/lhc_Undergound.htm. He mentioned important delays to the contractors planning for the injection tunnels but he concentrated his presentation on the status at point 1 and 5.

Most surface buildings at point 1 are expected to be largely completed, by the contractor, early in 2000, except for those that give access to underground work. The digging of the USA cavern is progressing well, but the ground movement recorded is greater than expected and it will require additional rock-bolting: 2 months extension of time has been awarded for this work, and the contractor is a further 1 month behind schedule. A 2 months extension was also awarded for PX14 and PX16, and the contractor is another 2 weeks behind schedule. The slipforming is delayed and will be carried out after the Christmas break. The excavation of the UX cavern is expected to start at the end of February 2000.

At point 5, work is progressing on the section 1 surface buildings (SX, SH and SY): 7 days of extension of time was awarded to the contractor, and the updated contractual completion date is the 10th of January 2000. It is unlikely that the buildings will be 100% completed at that time, but access to the SX building should be available. The digging of the PX54 shaft is 4 months behind schedule, due to the difficulty of the ground freezing. Excavation is to restart next week. The situation of PX56 is similar, ~5 months behind schedule. The start date for excavation is now anticipated for March 2000.

T. Watson also presented expenses profiles that are slightly behind the original planning for both point 1 and 5 (see Annex I), but the payments will probably go faster now. Important additional costs concern the imbedded steel plates in the SX5 building and the off-site drainage works at point 5 (> 1 MCHF). Notifications of claims for bad weather (25 days) and for the ground freezing problems have been issued. These will be discussed together with the delay penalties that may become due from the contractors.

G. Rau recalled the framework of the Convention between the French Authorities and CERN concerning the LHC, which is classified as an "Installation Nucléaire de Base" (INB). In order to simplify the procedure, the LHC is considered as an upgrade of LEP. Both LHC and SPS, as the LHC injector, will be included in the new convention.

The convention foresees many documents to be prepared by CERN:

• "Rapport préliminaire de sûreté" and "Rapport de sûreté démantèlement du LEP" to be ready 9 months before the start of the work (dismantling of LEP, installation of the LHC).
• "Rapport provisoire de sûreté LHC", "Règles générales d’exploitation" and "Plan d’urgence interne" to be ready 6 months before the first injection into the LHC.
• "Rapport définitif de sûreté LHC" and updates of the "Règles générales d’exploitation" and of the "Plan d’urgence interne" 5 years after the start of LHC.

We also have to submit an "Etude déchets" to explain what we plan to do with the equipment and waste coming from LHC related installations. The "Département de Sûreté des Installation Nucléaires" (DSIN) could stop the running of the machines and experiments if CERN does not satisfy all the requirements foreseen in the Convention.

The DSIN judged that the "Rapport de sûreté démantèlement du LEP" was not comprehensive and did not accept it. They want in particular a clarification of the dismantling of the experiments, a study of the handling of the waste and a quality assurance procedure.

A. Faugier will succeed G. Rau in charge of this long-term task.

H. Foeth pointed that the traceability required for the dismantling of DELPHI will not be ready on time. He advised that the inventory of LHC experiments should be done at the installation stage. P. Faugeras confirmed that this is indeed the case for the machine elements.

The TOTEM letter of intend was issued in August 97 and was well received by the LHC Committee and the Research Board, who asked the Collaboration to study a detector compatible with an already approved experiment. The Technical proposal with TOTEM at point 5, sharing the experimental insertion with CMS, was submitted in March 99. CMS responded very positively to this proposition, expressed its interest in the absolute luminosity calibration offered by TOTEM, and proposed a set of boundary conditions for the installation of TOTEM within CMS. The LHCC took note of this agreement and recommended the TOTEM experiment to measure the total p-p cross section. The Research Board (18/11/99) concurred with this decision and it invited the Collaboration to submit a TDR in line with the agreements reached with both CMS and the LHC machine.

W. Kienzle reviewed the recent activities of the Collaboration, concentrating on the integration with CMS and with the machine layout. He recalled that the Roman Pots are to be built with the help of the SL/BI group, in order to benefit from the experience gained with the design of the LHC collimators. A luminosity monitor, that needs to be radiation hard and linear up to luminosities of a few 10³⁴cm^-2s^-1, has been developed on the basis of a secondary emission counter (SEC) with the help of the PS/BD group. Other solutions, that are less sensitive to background and could provide fast coincidences, such as a cryogenic Si hodoscope or an array of Cerenkov detectors, will also be studied. I practice the monitoring of the luminosity will require multiple cross-calibration between several detectors.

W. Kienzle concluded that the TOTEM Collaboration is small and needs to grow stronger. He mentioned some contacts with various groups who expressed an interest in joining in the near future.

R. Veness asked about the removal procedure of TOTEM when the luminosity gets toward its design value. Werner recalled that the present challenge for TOTEM is to get in, not out! However, the TOTEM inelastic detector will not sustain a luminosity higher than 3-5 10³³cm^-2s^-1 and the precise de-installation scenario will have to be agreed with CMS. E. Tsesmelis agreed with this approach and recalled that the installation of TOTEM has an impact on the background, shielding and vacuum equipment in the experimental area.

K. Potter also mentioned that TOTEM expressed an interest to run at 1.8 TeV c.m. energy to get closer to the Coulomb interference region. B. Jeanneret asked about the need for the 3^rd Roman Pot station for total p-p cross section measurements: this station still allows a better background rejection and it is compatible with the collimators which are now foreseen in front of Q5 in the high luminosity insertions.

The second phase, including a proposal for the software protocol, is about to start. E. Tsesmelis recalled that the interlock, timing, video and communication procedures are not part of the mandate. He also pointed that no evaluation of the relevance of the requests will be made and that there will be no attempt to resolve any conflict. The main aim is to propose a reliable solution and to avoid people developing their own system.

K. Potter mentioned that the collection work should proceed up to 2005 and asked who will continue it in the future. P. Faugeras proposed to wait for the conclusions of the CO-OP forum that takes place 1^st-2^nd of December 99: there may be a need to set up a common body to continue an integrated follow-up of the work of the two groups.

(P. Faugeras – see transparencies in Annex 5)

The new planning takes into account the delays of the civil engineering work presented earlier by T. Watson. With a better knowledge of the important delivery dates, now that the work is in progress, it is possible to re-arrange the planning so that the completion of the machine does not shift. However, the difficulties encountered in the boring of the injection tunnels prevent any magnet installation through TI2 before 2003 and will delay the injection tests.

Concerning the main dipoles, 6 of the 90 pre-series magnets will be delivered in 2000 and 40 in 2001. The adjudication for the large series should occur at the end of 2001: dipoles will be received up to the end of 2004 and their installation goes up to the end of the machine completion. This date is now labelled "Ring closed" and not "Circulating beams", since TI2 might not be ready at that time. A large part of the commissioning can still be done with only one circulating beam: no access to the experimental areas would be possible during that time.

H. Foeth asked if the delay of the injection tests would change the access conditions at point 8 during the installation of LHCb: P. Faugeras foresees these tests during the nights and they furthermore should not interfere with the work on LHCb. There are still details of this kind to be agreed upon, and this explains why the full "train chart" is not yet on the WEB. In a similar line, the possibility to carry down main dipoles through the PX24 shaft, to overcome the delay of TI2, has been recently checked with ALICE and should be included in the planning.

• The "Access and Interlock working group" requires information on the access conditions foreseen by the experiments. Examples are the configuration of the CMS shielding with TOTEM detector installed, the status of the ATLAS magnet, access to the Roman Pots or to the ALICE zero degree calorimeter, etc … . A questionnaire is in preparation and will be sent out. Following a question from W. Witzeling, the 1 hour daily access to the UX cavern is confirmed.
• The PLC asked for a presentation of the LHCb vertex detector tank and moving system. The presence of a 100 m m Al foil close to the beam is a concern for the machine. The three other experiments also expressed their interest in such a presentation.

The next LEMIC meeting is scheduled for the 15^th of February.

The following dates are proposed for further meetings in 2000:

28 March

9 May

13 June

18 July

5 September

17 October

28 November