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A few selected high-lights since the last Collaboration meeting at Stockholm (They are taken from the very recent yearly ATLAS presentation to the open session of the LHCC) The main messages delivered there were (copied from the conclusions):
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A few selected high-lights since the last Collaboration meeting at Stockholm (They are taken from the very recent yearly ATLAS presentation to the open session of the LHCC) The main messages delivered there were (copied from the conclusions): Many important milestones have been passed in the construction, pre-assembly, integration and installation of the ATLAS detector components The most critical construction issue is the delay in the ECT integration, which has an impact on the overall installation completion (other issues remain the schedules for the ID and Muon end-cap chamber installations, and the calorimeter power supplies) Very major software, computing and physics preparation activities are underway as well, using the Worldwide LHC Computing Grid (WLCG) for distributed computing resources Commissioning and planning for the early physics phases have started strongly ATLAS is highly motivated, and on track, for first collisions in 2007 and finally LHC physics in 2008 Response from the LHCC: By large very positive, transmit congratulations to the whole Collaboration!
Solenoid July – August 2006: The solenoid has been fully commissioned in-situ up to 8.0 kA The operation current is 7.73 kA for a field of 2.0 T Successful accurate field mapping 1st August 2006: the solenoid is fully operational
Wait for closingTile End-Caps Ramp in steps:7730 A = 2 T repositioningaccuracy±0.1 mm final position 0.0 ± 1.4 mm (relative IP) Excitation to full field: 8 kA (1 August) 7730 A2.00 T 7980 A voltage(blue) slow dump current(red) Coil length shrinkage, linear to I2
Field Mapping • 3D calibrated Hall probes • Accuracy: ±1x10-4 T (at ≤1.2T)(Felix Bergsma, CERN) • Excitation reproducibility • Field: < 0.1x10-4 T • Current: < 5 ppm • No hysteresis effect from iron • iron contribution to field: ~ 3.5 % • Data confirms coil positionfrom survey and monitor system: • horizontal offset: 0.1 mm • vertical offset: -2.3 mm Field measurement team
Higher winding density Conductor joint missing one-turn to be studied Comparison Calculated / Measured Field Very accurate: Possible to identify detailsin winding structure After first corrections (@ 5kA): • +7x10-4 ~ -13x10-4 T improvements in progress Detailed talk Thursday 10h30 by Heidi Sandaker Fit using simple helical conductor model (large radius) [courtesy S.Snow] small radius[courtesy H.Sandaker]
Barrel Toroid test in 3 phases step-by-step cleaning of cavern from iron & safety access control Phase 1 (27 Sep - 8Oct) : <300A static, ~10mT on vessel surface • Removal of green platforms and other large loose objects • Test of toroid inductance, resistances, RRR, fine tuning of coil cooling, sensors, identification of quench heaters etc. Phase 2 (9-20 Oct): 1-5 kA, static and 10mT/s field rate during quench • Removal of all iron platforms and scaffolding within BT area • Magnet Safety System test, power supply adjustments, slow and fast dumps, quench heater tests, check of coil mechanics Phase 3: 5-20 kA (20 Oct- Dec), static and up to 50mT/s field rate • Mandatory removal of all old and loose iron from the cavern including HS&HO areas and strict access control for new iron including tools! • Step by step increase up to 20kA, slow and fast dumps at 5-10-15-18-20kA and check of coil mechanics, cooling, hot spot temperatures
AFT redesign and repair in Sep-Oct 06 • ECT cold mass is pulled into the BT with ~260 tons taken by 16 tie rods that transfer load to the vessel and then to the 8 BT vessels trough the 8 AFT connection points • Design assumed infinite stiffness of vessel during integration and 0.5mm tolerances • Impossible to do, they may brake! • Redesign to make them adjustable after closing, transport, cooling down in cavern • Bring the AFT connections through the end plate to the outside, 16 new feed-throughs • Connect extension rod New vacuum seal Nut for adjustment • Problem solved, but it takes time….
Schedule ECT-A • Closing vessel Oct-Dec 06 • Vacuum test during X-mass • Preparations for transport Jan 07 • Transport to 80K test station ~1 Feb • Transport to point 1 in March • Connections and test in cavern Mar-Jun 07 ECT-C • Cold mass ready by Dec 06 in B191; cryostating can not start before ECT-A is out of B191 • Cryostat integration Feb-Apr 07 • Vacuum test and preparations for transport May 07 • 80K test in May-June • Transport to point 1 by end of June • Connections and test in cavern by Jul-Sep 07 !
Inner Detector: highlights and concerns • ID Barrel installed in pit and connect/commission just started, its weight measured and agrees fairly well with simulation. • B-field measured and fast feedback on optimal detector position • Satisfactory tests on evaporative cooling final system done • Steady progress on EndCap integration • Impressive progress on Pixel integration. • Concerns in Jul06. and now: • TRT • SCT • Pixel • Low mass (type0) Al cable cracks • IDGEN • Service installation • TRT • SCT • Pixel • Optoboards failures • IDGEN • Service installation
TRT+SCT barrel travelled to the pit, 24th Aug 2006 A tight fit between BT and EC Calorimeter Through the parking area Now: cabling up (rest of the year!) From the trolley to the support rails Inside cryostat
ECC insertion started Friday last, went all way through but at the last cm there was a short. A G10 insulation layer is being added, expect insertion completed today.
ECA • TRT: Hydraulic tests done and ok. HV lines tested (13 need to be replaced). Electronics tests started a week ago. Planned to be ready for SCT integration by late October. • SCT: many small mods needed (tight tolerances), e.g. relay fibers to maximize length outside. Date for integration with TRT delayed to Nov 13 no time for combined cosmics test. Effort must be done to at least dig out a time slot for combined noise measurements. Install end of january 2007…
Lot of progress on the Pixels! Pixel ECs at CERN Pixel Layer-2 – half shell New manpower (also NIKHEF) Latest worry: optoboards (vcsels!) Pixel Layer2, once clamped, inside
LAr Summary • Cryostats: • Barrel: Refilling with LAr did not solve all HV problems • End-cap A: Preparing for cool-down in Nov-06 • End-cap C: Cool-down to follow after ECA is cold. • Electronics board production nearing completion for both FE and BE • LV PS: • A technical team is being set up to evaluate whether recent failures are due to a design problem or due to weak Q/A. • Rate of ‘good’ modules is still low due to bad workmanship. • HV PS: • The technical solution reported in July seems to be stable • Have seen Q/A problems in recent delivery.
Stable situation detector temperatures • Tmin = 88.2 K • Tmax = 88.6 K • Detector sub-cooled between 5.8 K and 8.6 K • (below vapor pressure curve). Stable in time LAr Barrel Steady State Stable pressure situation in expansion vessel Impurity level Measured with four purity cells: (0.20 +- 0.05) ppm O2
LAr Barrel HV Status • HV status at an early stage of commissioning: • 1600 V on Calorimeter, 2000 V on Presampler, leaving out known problematic channels. • Status on Calor: 2 sectors HV shorts, 10 sectors working with half of the signal, out of 448 independent sectors • Status on presampler: 7 (/256) problems, will try to burn them. • Problematic channels will be dealt with separately. • Decided on HV strategy for next few months: • Leave HV on EMB calorimeter off when not needed, • Put 1600 V on 6 – 8 modules needed for cosmics data taking with tilecal.
There are problems with power supplies (LV and HV, both LAr and tiles) - quality - quantity (ATLAS,CMS,ALICE,LHCb orders at CAEN > CAEN capacity) But I don’t know details, nor how serious this is…
Event display from the first LAr + Tile Calorimeter barrel cosmics run Correlation between LAr Middle & Front layer
Barrel Chamber Installation • 514 barrel MUON Stations have been installed on rails (~74%), not all of them in final position
Muon Installation Status ( 1-10-2006) 5 4 6 3 7 2 8 US USA 1 9 16 10 Blue: completed Green: completed on one side Red partly installed 11 15 14 12 13
Service installation status: MDT • MDT HV-LV cables installed for all outer chambers • Production and installation under way • MDT Alignment cables Installed for most of the chambers • MDT DCS daisy chains cable produced for most of the chambers and installed on upper sectors (1,2,3,4,5,6,7,8,13) • MDT RO/TTC fibers: Installed on most of the upper sectors and partially connected to chambers (mainly BOS) • Gas connections Chambers to Manifold started in many sectors (BOL, BOS, BIL, BIS)
DCS PCs and Power crates AlignmentPCs MDT DCS and Alignment • All DCS computers Installed in USA15 • CANbus Power crates installed • Read-out of DCS chains in more than 115 chambers on the upper sectors is performed with final system. (R. Hart) • All Alignment Computer Installed in USA15 • Many sectors cabled and tested with final system • First 4 projective alignment lines read-out in sector 13 • Reference System will be used for monitoring the BT deformations during the magnet excitation.
Combined MDT+RPC+Tile run ATLANTIS display of an event from the combined MDT+RPC+Tile run taken middle of august. Run #1002 , event # 50 The µ-segment in the Muon System was reconstructed with Moore Collaboration of Tile and MS community E. Feng, S. Rosati, S. Veneziano :
RPC Theta (rad) MDT Theta (rad) • = 0.74 cm ≈ pitch/√12 A tool for RPC commissioning M. Biglietti M Della Pietra F. Conventi D. Della Volpe Results of the tracking: RPC vs MDT correlation Good tracking resolution on all planes Good correlation between the angle in the r-z view reconstructed by Athena with MDT and by this code for RPC
ATLAS was honoured last week by a visit of Stephen Hawking Simulation of a mini black hole event with MBH ~ 8 TeV in ATLAS
The 1000th cryomagnet was installed in the tunnel on 5th September (out of 1746 total) The Dash Board for the dipoles (1232 total in LHC) on 31st August
Photo 0903 Acceleration RF Cavities Tunnel installation • All main RF equipment now installed in the tunnel at point 4 having been fully tested and vacuum conditioned on the surface - 400 MHz accelerating cavities - 16 cavities in 4 modules, 2 per beam. - Transverse damping kickers - 16 electrostatic deflectors, 8 per beam - Longitudinal monitors – 6 wideband coaxial line monitors • Alignment is in progress, beam tube vacuum connections in one month. • Cryogenic, cable and waveguide connections still to come. • Power amplifiers for dampers (installed under kickers) for early 2007. On target for 450 GeV run
LHC Commissioning Sequence Machine is closed (Aug 07) Hardware commissioning needed for 450GeV plus maximum possible for 7TeV Nov/Dec 2007: Beam operation with collisions at 450 GeV Shutdown: Finish hardware commissioning and installation of some delayed equipment for 7 TeV (e.g. some collimators). LHC commissioning for 7 TeV physics. LHC Operation
Summary of LHC Hardware Commissioning Goals • During 2007: fully commission 4 sectors and partially commission other 4 • Hand over machine to operations 1st Nov.2007 • During 2008: (re)commission all sectors to 100% in the first 3 months. • Hand over machine to operations on 1st April 2008
Time (from Nov 1 2007?) Given an operational efficiency of 60%, this gives an elapsed time of about 26 days.
LHC is approaching completion. • LHC commissioning is prepared (in detail.) • 450 GeV collisions run in 2007. • LHC collisions at 7 TeV in 2008 (possible luminosities, around 1033 cm-2 s-1). • Finalised plan after the 450 GeV run • More physics
LHC Schedule • A CRAG (Commissioning and Running Advisory Group) meeting was convened on 1st September, with participation of all its members (J Engelen, L Evans, S Myers, M Della Negra, T Nakada, J Schukraft, Peter Jenni, M Ferro-Luzzi, and M Mangano) • L Evans confirmed the June LHC installation schedule, being very confident that the recent months have shown that the milestones will be reached • S Myers was cautious, but commented that it is realistic to plan for a couple of weeks of 900 GeV collisions in 2007 • The plan is to have the machine on open access January-March 2008, and have then the experiments closed again on 1st April 2008, followed by a few (~3) weeks of controlled access • The working schedule has then as target date for first 14 TeV collisions the last week of June 2008 (obviously not a hard date) • The experiments were asked to present at the next CRAG (no date yet, maybe early October) their wishes for the 2007 run Note: S Myers has accepted to give a presentation on Friday morning