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ATLAS first run scenarios

ATLAS first run scenarios. Paula Eerola, Lund University 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006. This talk includes:. ATLAS status From H. Burckhart, ”ATLAS Detector and Commissioning Status”, Beauty 2006, Sep 2006 A summary of the LHC start-up scenario

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ATLAS first run scenarios

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  1. ATLAS first run scenarios Paula Eerola, Lund University 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  2. This talk includes: • ATLAS status • From H. Burckhart, ”ATLAS Detector and Commissioning Status”, Beauty 2006, Sep 2006 • A summary of the LHC start-up scenario • The LHC commissioning run (450 GeV + 450 GeV) until the end of 2007 • The first physics run at 14 TeV Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  3. ATLAS Layout • Tracking (||<2.5, B=2T): • -- Si pixels and strips (SCT) • -- Transition Radiation Detector (TRT): e/ separation • Calorimetry (||<5): • -- EM : Pb-LAr • -- HAD: Fe/scintillator (central), Cu/W-LAr (fwd) • Muon Spectrometer (||<2.7) : • air-core toroids with muon chambers (MDT, CSC) Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  4. Pixel status All modules have been delivered with good yield. End-Caps: Both EC have been integrated, delivered at CERN and acceptance tested. Cosmics tests starting in October. Barrel: Stave production is completely finished. Layer2 has been integrated, Layer1 integration is proceeding. The best staves (least dead channels, best thermal performance) are reserved for the b-layer, integration planned for November. Pixel ready for installation April 2007. Pixel ECC, 3 disks visible Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006 Pixel Layer2 – Half shell Pixel Layer2 clamped

  5. SCT status Completed SCT End-Cap disk SCT Barrel 6 (Picture taken by a star-photographer, P. Ginter, as art-work…) (Picture taken at Oxford) Both End-Caps ready for insertion in TRT: EC C this week, EC A in November Ready for installation January 2007 Barrel SCT (+ TRT) installed Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  6. SCT Barrel Integration Barrel 6 insertion into thermal shield Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  7. TRT Barrel Barrel TRT during insertion of the last modules (February 2005) Now installed in cavern Cosmics in the barrel TRT Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  8. TRT End-Caps • Barrel: 52k straw tubes • 4 mm diameter • 150 cm long • 36 layers, • r = 56-107cm • End cap: 320k straw tubes • Straw resolution 170 μm • Total volume: 16 m3 A and B type TRT end-cap wheels fully assembled Both TRT End-Caps are ready for integration with the SCT Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  9. SCT in TRT Barrel Insertion Barrel TRT Barrel SCT End of February 2006 the barrel SCT was inserted into the barrel TRT Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  10. Cosmic track in SCT/TRT Barrel Dead channels: SCT < 0.2% TRT < 1.5% Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  11. Transport of SCT/TRT Barrel on 30.August 2006 Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  12. SCT/TRT barrel in its final location inside calorimeter Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  13. Tile barrel Tile extended barrel LAr hadronic end-cap (HEC) LAr EM end-cap (EMEC) LAr EM barrel LAr forward calorimeter (FCAL) Calorimeter Layout Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  14. 27 Oct. 2004:Lowering LAr cryostat LAr positioning Mounting Tilecal modules 1 Dec 2004:58 Tile modules mounted Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  15. Barrel LAr and Tile Calorimeters A cosmic ray muon registered in the barrel Tile Calorimeter The barrel LAr and scintillator tile calorimeters in the cavern in their ‘garage position’ January 2005 Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  16. Barrel Toroid installation Barrel Toroid coil transport and lowering into the underground cavern Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  17. The first coil was installed in October 2004 The last coil was moved into position on 25th August 2005 Cool Down: started 4 July 2006 31 August 2006: 4 K Test with full current in October Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  18. Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006 (ATLAS Christmas card 2005)

  19. End-Cap Toroid All components are fabricated, and the assembly is ongoing at CERN The first of the two ECT cold masses inserted into the large vacuum vessel Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  20. Muon Spectrometer Instrumentation Precision chambers: - MDTs in the barrel and end-caps - CSCs at large rapidity for the innermost end-cap stations Trigger chambers: - RPCs in the barrel - TGCs in the end-caps The Muon Spectrometer is instrumented with precision chambers and fast trigger chambers At the end of February 2006 series chamber production in the many sites was completed. Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  21. Barrel MDTs Installation of barrel muon station (65% done) A crucial component to reach the required accuracy is the sophisticated alignment measurement and monitoring system Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  22. First cosmics registered in situ for barrel chambers In December 2005 in MDTs and in June 2006 in RPCs Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  23. First TGC Wheel fully installed Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  24. Installation summary • ATLAS installation and commissioning proceeds well • Inner Detector • SCT/TRT Barrel already installed • SCT/TRT End-Caps ready for installation early 2007 • We expect to have a complete 3-hit Pixel system installed at start-up • All Calorimeter components already installed, now being commissioned with cosmics • Installation of Muon system ongoing Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  25. Commissioning • Stand-alone operation of a subdetector • Integration of each subdetector in central systems (Trigger, DAQ, DCS, DB, Monitoring, Offline) • Integrated Cosmics data taking • Data taking with beam • Single beam • Collisions at 2 x 450 GeV Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  26. The commissioning run • Beam pipe closure end of August 2007 • LHC commissioning run with collisions at the injection energy (√s =900 GeV), scheduled November 2007 • Luminosity typically • L = 1029cm-2s-1 • The LHC will be a static machine, no ramp, no squeeze, to debug the machine, the detectors and the data processing • A few weeks of stable running conditions at the injection energy Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  27. Triggers for the commissioning running • √s = 0.9 TeV, L = 1029cm-2s-1, sinel=40 mb <=> 4 kHz interaction rate • Commissioning the detector, the trigger, the offline reconstruction and analysis chains • Data taking with loose level-1 (LVL1) single muon triggers (pT>5 GeV) or minimum bias triggers • The High Level Trigger (HLT) in pass-through mode for testing • Minimum bias trigger techniques • Bunch-crossing LVL1 trigger + selection at LVL2 and/or EF • Detectors • Minimum-Bias Trigger Scintillators (MBTS) using precision readout • Inner detector (pixels sensitive to low pT) • LUCID and other forward detectors? • Calorimeters? • MBTS trigger at LVL1 (followed by further selection in HLT) • Some bias at LVL1 (h range; efficiency for minimum-ionizing particles; multiplicity requirements; etc.) • Needed at very low luminosity where interactions per BC << 1 Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  28. W  e Z  ee bb  m5m3X pp + bb  J/Y(m5m3)X √s=900 GeV, L=1029cm-2s-1 Event statistics for the commissioning run 30% data taking efficiency included. Efficiency of trigger and analysis cuts included. Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  29. √s=900 GeV, L=1029cm-2s-1 h  m5 X bb  m5 X bb  m5m3 X pp   (m5m3) X pp  J/y (m5m3) X bb  J/y (m5m3)X Number of events in ATLAS after all cuts 30% machine and data taking efficiency assumed. Reconstruction and trigger efficiencies included. Number of days of data taking Event statistics with B and Quarkonium muonic decays Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  30. The first physics run • √s = 14 TeV, L = 1032-33cm-2s-1 • The aim is to integrate several fb-1 by the end of 2008. • Many customers for the data • Data for commissioning the detector, the trigger, the offline reconstruction and analysis chains • Data samples high-pT physics studies • Sharing of “bandwidth” between different triggers • Plus control samples to understand the backgrounds, measure the selection efficiency, etc • Data samples for B-physics studies • Scope depends on luminosity and available HLT resources • Data samples for “minimum-bias” physics studies • Needed also for tuning Monte Carlo generators used in other physics studies Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  31. Minimum bias on day zero? Why measure min bias? Not exactly what the LHC was built for! But….. • Physics: measure dN/dh|h=0 • Compare to NSD data from SppS and Tevatron • MB samples for pile-up studies • Calorimeter • Physics analyses • Overlap with underlying events • analyses eg VBF, Jets… • Demonstrate that ATLAS is operational • Inter-calibration of detector elements • Uniform events • Alignment • Baseline for heavy ions C. Buttar, ATLAS Physics Week May 2006 Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  32. Event characteristics • Event characteristics • Non-single diffractive~non-diffractive inelastic • Soft tracks pTpeak~250MeV • Approx flat distribution in h to |h|~3 and in f • Nch~30; |h|<2.5 • Trigger rates • s~70mb (NSD!) • R~700kHz @ L=1031cm-2s-1 • Rapidity coverage • Tracking covers |h|<2.5 • pT problem • Need to extrapolate by ~x2 • Need to understand low pt charge track reconstruction h 1000 events Reconstruct tracks with: 1) pT>500MeV 2) |d0| < 1mm 3) # B-layer hits >= 1 4) # precision hits >= 8 dNch/d dNch/dpT Black = Generated (Pythia6.2) Blue = TrkTrack: iPatRec Red = TrkTrack: xKalman M. Leyton Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006 C. Buttar pT (MeV)

  33. 50MeV Low pT Min Bias Track Recon • Tracker is in principle sensitive to soft tracks • Pt = 400 MeV - tracks reach end of TRT • Pt = 150 MeV - tracks reach last SCT layer • Pt = 50 MeV - tracks reach all Pixel layers • Strategy 1: Primary track reconstruction • Strategy 2: Secondary track reconstruction • New Strategy: Soft particle reconstruction after primary vertexing A.Salzburger Elsing 400MeV 150MeV Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  34. Tracking: Startup-Initial Alignment • Very first alignment will be based on: • Mechanical precision • Detailed survey data • Cosmics data (SR1/Pit) • Minimum bias events and inclusive bb • Studies indicate good efficiencies after initial alignment • Example taken from T.Golling • Precision will need Zs and resonances to fix energy scales, constrain twists, etc… M.Elsing Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  35. B cross-section at LHC • All LHC experiments plan to measure B-cross section in proton-proton collisions. • Measurements will cover different phase space – will be complementary. • Partial phase-space overlaps: LHCb, ATLAS, CMS, ALICE - opportunity for cross-checks. • Methods of measurement for low- and medium-pT events in ATLAS • bb  m6 X ; • bb → m6m3 X; • Exclusive channels B+→J/y K+, B0→ J/y K0* • b-b correlations: B→J/y X +b m Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006 Df=f J/y - fm

  36. Statistics for bb-events Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  37. B, J/y and  measurements Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  38. Hadronic top with 100 pb-1 3 jets with highest are used to form top 34% electron-events have exactly 1 electron pt>25GeV L1 trigger “EM25I “ 9.6% has exactly 4 jets (Cone0.4) pt>40GeV The fourth jet • 91% etmiss>20GeV Zhu Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  39. Top masses No trigger+pT(elec)>25 GeV Trigger=EM25I or MU20 Hadronic top Leptonic top (no W in-situ calibration)  Reconstructed top mass distributions not affected by trigger Pralavorio Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  40. Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  41. Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  42. Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  43. Commissioning run at 900 GeV, very low luminosity Commissioning of the detector, the trigger, the offline reconstruction and the analysis chains. In 30 days ~4.7k single muons and ~370 di-muons from b and c: first tests of trigger and offline muon reconstruction. 90 J/y and 130 : first tests of mass reconstruction. First physics run at 14 TeV, 100 pb-1 – 1 fb-1 Understanding the detector – alignment, material, magnetic field, event reconstruction etc. Standard Model Physics: Minimum-bias physics and cross-section measurements at new energy for QCD tests and optimization of trigger strategies. B, J/Y and  measurements. Top-physics. Beyond Standard Model: e.g. inclusive SUSY searches! Conclusions Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  44. Thank you! Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  45. BACKUP SLIDES Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  46. single-muon all h b c b all b h di-muon J/y c Sources of low-pT single and double muons LVL1 muon trigger rates @ 14 TeV and 1033cm-2s-1 • The figure shows sources of low-pT muons at 14 TeV. • Muons from hadron decays in flight (“h” in the figure) have a softer spectrum than muons from b. Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

  47. Detector configuration during the first physics run • B-layer OK. • ID complete, only TRT C-wheels staged • HLT configuration: full 45kHz LVL1 capacity. Paula Eerola 13th Nordic LHC Physics Workshop Helsinki 26-27 October 2006

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