Muon Stations M2-M5 Hardware status Outline: Gas System status UF/PNPI HV-system status Remaining M2-M5 installation tasks – Air cooling system status – Rack cooling – DSS related issues – Moving system Closing test and alignment status Burkhard Schmidt

Gas System Commissioning Status: The common gas analysis rack has been commissioned in the past weeks and the values for the water contamination, measured with different devices make finally sense. We have about ppm of H 2 O and 30ppm of O 2 in the return line. (Values went slightly down with new calibration of H 2 O meter.) A software upgrade took place last week and we have now the gas analysis available online The commissioning of the M1 gas racks is ongoing and will be completed by July 11. The GEM part maybe only a bit later, as some more work is required still. All chambers are flushed since April 10 with the (CO 2 /Ar 60/40) for cost reasons: –CF 4 for 1day in vented mode operation costs 1000 CHF. –CF 4 for 1day in recirculation mode costs 100 CHF.  We intend to continue running without CF4 until colliding beams are within reach  The system is running very stable.

Gas System Commissioning To be done still: Recalibrate some flow cells in the distribution racks. (Gas Group) Move the test chamber to the UXA zone for continuing checks on the gas quality. (CBPF expressed interest) Display some gas system information in the Muon ECS and define thresholds for actions. (Florence group?) 14/4 15/4 16/417/4

UF/PNPI HV-System Hardware (PNPI): Spare modules of RDBs (5), Masterboards (2) and Hostcards (2) are available at CERN and calibrated. Software: Four components exist: 1.PVSS  Michela (Firenze) 2.DIM server  Magnus (CERN/DO) 3.Driver for Host-card  Evgueni (PNPI) 4.Firmware for FPGA  provided by UF  People in charge for all 4 parts are better identified.  3. and 4. will obviously change when we go to the USB interface (discussions with MSU only started) 14/4 15/4 16/417/4

UF/PNPI HV-System Status: We got new Driver and Firmware from CMS (UF). The Driver has been upgraded by Evgueni to run under SLC4 and tested. The new Firmware has not been installed yet. Planned for next week. The problems observed with modules turning off disappeared since we use the new Driver. The system needs more debugging at several levels, which is ongoing. Presence of people at CERN is important for the debugging. 14/4 15/4 16/417/4

Air Cooling System Status Cooling hoses are installed on the A- and C-side. Additional cables to power the blowers with 400V/32A are in place. Space for the blowers has been made in the base of the M2-M5 support structure, retaining the same mass as we had before. Blowers have been installed in May. Heat exchangers, filters and distributors for the cooling hoses need to be installed still. It will take at least 2 weeks to complete the system  We are late due to lack of manpower and the rather low priority given to this system.  The temperature in the detector has to be monitored carefully by us in this phase where the cooling system doesn’t work yet.

Rack Cooling Turbines are operational since many months and the rack cooling is not really a problem. However, optimal cooling is desirable to improve longevity of the electronics, in particular the ODE boards. Therefore:  Heat exchangers should be connected  Racks should be closed properly (also important in case of fire!) Investigations on rack temperature and on optimal position of the heat exchangers are in progress (Nikolai) Rack cooling could be completed within the next 2-3 weeks if manpower is made available (move Gennady to this task ?)  We are late due to lack of manpower and the rather low priority given to this system.

DSS Issues Water Leak Detection (WLD): WLD will be done with special water leak detection cables. Material ordered, should be delivered and installed soon (Nikolai). Recipients will most likely not be installed (lack of space). Gas System / HV-interlock: Problems with the Gas System provoke a DSS signal now. The HV-interlock needs still to be cabled up. A 3-6 hour delay before cutting the HV for the chambers is foreseen.

Control of Moving System (Marco, Laurent, Nikolai, Robert) System for station movement is in place and has been partially used for the closing test. Some more work is needed to complete the installation (mechanical and electrical aspects) and to test the system.  Planned in the coming 2 weeks. Control system for the Filter moving is not yet complete (cupboard with electrical circuitry needs to be assembled, installed and tested) Some improvements are desirable after the experience gained with the closing of the system in the past week.  It will most likely take until the second half of July to complete everything.

Operating Procedure for the moving of the Muon Filters and Muon stations An operating procedure has been prepared with high priority after the incident of May 19, when 4 aluminum plates fall from MF2 (A-side) EDMS document  Please, read it carefully

Control of Moving System First measurement results for Muon Filters: Reference: control of reproducibility of result Closed: after first complete closing on Friday Closed: after moving the filters 4mm direction cryogenics mm

Closing Test

Much preparation work was needed –Chamber supports (baloconies) –Rerouting of Cables, change of screws Work of Oleg and Sasha was very Much appreciated

Closing Test Additional guides

Closing Test Much preparation work was needed A small gap (5-10mm) remains in the centre, despite the modification of a vertical plate Filter (beam plugs) with +/- 5mm In their nominal position)

Station Alignment A very difficult job (mainly done by Thomas), which is unfortunately not yet completed, despite many measurements taken by Sandra and Jean-Christophe and subsequent corrections (help of Wander appreciated). C-side station alignment: Could be verified in the final station position and is rather good. A-side station alignment: Could only been done so far with the A-side filters opened. Unfortunately the inclination of the M5A (also M4A?) wall in the x-y-plane changed by about 4mm when moving to the closed position, so the alignment has been partially lost. M2A (also M3A ?) looks rather ok.

Station Alignment Measurement with position encoders (end-switches), reference done in open position, the other measurements in the closed position Measurement shown is for end-switch on MF3 A-side, close to M5A) mm

Summary Station Alignment Station z-alignment (A- and C-side): We are within 4-5mm in the nominal position. Final z-values are driven by gaps between the filters, clearances etc. ok C-side: y- alignment:ok x-alignment: Moving M3-M5 1.5mm to the beam axis brings all stations within 1mm relative to each other in x and ensures symmetry around x=0  should still be doable in the coming weeks A-side: y-alignment: looks ok for M2A (M3A ?). Tilt of M5A spoils y-alignment  Needs checks and new measurements, which can not be done with ECAL/HCAL closed. To be seen. x-alignment: Moving stations M3 and M4 3mm out and M5 even 6mm brings all stations within 1mm relative to each other and ensures symmetry around x=0  should be doable in the coming weeks, but difficult to re-measure.

Summary Station Alignment Final station Offset: With the values given on the previous slide we would have a station offset of mm.  Given the poor quality of the Muon filter closing around x=0, this is in my opinion acceptable. New measurements of the system when closed would be very desirable. In case the calorimeters cannot be opened with the beam-pipe under vacuum, a new strategy needs to be developed with the surveyors for doing such measurements. The clearances around the beam plug need to be re-measured for the A- side with the system closed. Should be done as soon as possible. With the values given on the previous slide we expect clearances around the beam-plugs of at least 5mm, which are desirable.

Conclusion A non negligible number of small tasks remain to be accomplished in the coming weeks, which require our concerted efforts. In addition we have to reserve some time to clean the zone and remove material we don’t want to be subjected to INB rules later on.