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CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop CERN – June 15 -16, 2009 CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop CERN – June 15 -16, 2009 Gervasio Gómez for the CMS Collaboration CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009

CMS Muon System Return iron Yoke in red Y Endcap Disks: Cathode Strip Chambers CMS Muon System Return iron Yoke in red Y Endcap Disks: Cathode Strip Chambers (CSC) X Yoke Endcap: YE Z Yoke Barrel: YB Barrel wheels: Drift Tubes (DT) CMS Hardware-based Muon Alignment Resistive Plate Chambers (RPC) in both barrel and endcap LHC Detector Alignment Workshop, June 15 -16, 2009 2

CMS Muon System Muon Barrel (MB) stations Muon Endcap (ME) stations 4 DT stations CMS Muon System Muon Barrel (MB) stations Muon Endcap (ME) stations 4 DT stations in 5 barrel wheels and 12 phi-sectors: 250 DTs 4 CSC stations in 3+3 endcap disks and 16 phi-sectors: 540 CSCs CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 3

CMS Muon Alignment System: Barrel • Alignment of 250 Drift Tubes w. r. t. CMS Muon Alignment System: Barrel • Alignment of 250 Drift Tubes w. r. t. each other • Redundant network of optical connections • MAB: Module for the Alignment of the Barrel • Rigid carbon fiber structure housing cameras • Some also contain Link components • LEDs mounted on DTs are read by cameras mounted on MABs • Z-bars provide better z-resolution CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 4

CMS Muon Alignment System: Endcap • Relative alignment Cathode Strip Chambers w. r. t. CMS Muon Alignment System: Endcap • Relative alignment Cathode Strip Chambers w. r. t. each other. • Network of optical connections complemented by inclinometers and axial and radial distance meters. Straight Line Monitors: • 3 per Muon Endcap station • Laser lines read by Digital CCU Optical Position Sensors (DCOPS) Z-sensors • Relative z distance between Muon Endcap stations Transfer lines • SLM across z, measure relative x, y displacements between ME stations CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 5

CMS Muon Alignment System: Link LD AR MAB Alignment of DTs and CSCs in CMS Muon Alignment System: Link LD AR MAB Alignment of DTs and CSCs in a common frame of reference related to the tracker. Network of optical connections complemented by inclinometers and axial and radial distance meters Lasers from Alignment Rings (AR) to Link Disks (LD) at Yoke Endcaps YE± 1, deflected and read by Amorphous Silicon-strip Position Detectors (ASPD) mounted on Muon Endcap ME± 1 chambers and on MABs on Yoke Barrel YB± 2 CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 6

CMS Muon Alignment System YE+1 LD YB+2 DCOPS AR Link line SLM CMS Hardware-based CMS Muon Alignment System YE+1 LD YB+2 DCOPS AR Link line SLM CMS Hardware-based Muon Alignment ASPDs MAB LHC Detector Alignment Workshop, June 15 -16, 2009 7

CRAFT Alignment Results: DT • Full DT geometry reconstruction in progress – Processing ~7000 CRAFT Alignment Results: DT • Full DT geometry reconstruction in progress – Processing ~7000 optical measurements • Recent milestones – Calibrated all 250 DTs • LED positions on DTs – Calibrated all 36 MABs Sector 7 MAB • Camera positions inside MABs – Automated DQM: discard bad LEDs – Working offline geometry reconstruction model Sector 8 – Initial partial DT geometry reconstruction at 3. 8 T • Only one active plane • Stability over 1 week at nominal field < 40 mm – Partial geometry reconstruction at 0 T compared to Photogrammetry/Survey • MAB z, rf positions compatible at the sub-mm, 10 -2 mrad level • DT positions compatible at the mm, 10 -1 mrad level CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 8

CSC alignment strategy • • – – ME 2, 3, 4 Start with survey CSC alignment strategy • • – – ME 2, 3, 4 Start with survey (0 T) Add relative shifts from 0 T to 3. 8 T from Z-Sensor measurements Fit all ME± 2, 3, 4 SLMs and reconstruct CSC positions: ZCMS and x’ – Disk Center Ideal YE+2 YE+3 ZCMS [mm] mm 8820 8828. 3 9900 9906. 5 YE-2 YE-3 -8820 -8821. 6 -9900 -9903. 1 -3. 1 ME 1 Start with geometry reconstructed by Link system – Also use Z-sensor measurements Fit all SLMs and reconstruct CSC positions: ZCMS and x’ CMS Hardware-based Muon Alignment Survey [Aug 08] ∆Z LHC Detector Alignment Workshop, June 15 -16, 2009 z’ = ZCMS y’ CSC x’ 9

Endcap Disk Bending at 3. 8 T SLM 1 SLM 2 SLM 3 B=3. Endcap Disk Bending at 3. 8 T SLM 1 SLM 2 SLM 3 B=3. 8 T CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 10

CRAFT Alignment Results: Link Movement of structures under magnetic forces Only the +z side CRAFT Alignment Results: Link Movement of structures under magnetic forces Only the +z side of the link system could be reconstructed during CRAFT ~DZ(YE+1, YB+2) Final closure of disk after large B-field is applied 21 -Nov 25 -Aug Elastic deformation of disk 3. 8 T CMS Hardware-based Muon Alignment 21 -Nov 25 -Aug 0 T LHC Detector Alignment Workshop, June 15 -16, 2009 11

Disk movement from 0 T to 3. 8 T form Link – YE+1 Z Disk movement from 0 T to 3. 8 T form Link – YE+1 Z displacement of 12. 47 mm towards IP – ME 1/2 chambers are left behind by 1 -3 mm – They are also tilted about 3. 5 mrad YE+1 @ B=0 T YE+1 @ B=3. 8 T Relative displacement in mm in absolute CMS coordinates. Relative orientation in local chamber axis in mrad ME 1/2 ME 1/1 ME 12 ΔX ΔY ΔZ Ang_Y Mean 0. 21 -0. 16 2. 19 -3. 45 Ang_Z 0. 05 12. 47 mm CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 12

0 T to 3. 8 T: Link vs Endcap ME 12 CSCs are reconstructed 0 T to 3. 8 T: Link vs Endcap ME 12 CSCs are reconstructed independently by link and endcap • Differences in position/orientation of ME+1/2 chambers between LINK COCOA fits at B=3. 8 T and B=0 T • Corresponding ENDCAP numbers: Agreement: X, Y: ~30 mm Z: ~190 mm CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 13

0 T vs 3. 8 T: Link vs Barrel Compare Z-compression of Link-reconstructed MABs 0 T vs 3. 8 T: Link vs Barrel Compare Z-compression of Link-reconstructed MABs with Z-compression of DTs from partial DT reco • Link-reconstructed position/orientation of the 6 MAB’s in YB+2 wheel: 1. 4 mm (-z side) 1. 7 mm Shortening at 3. 8 T wrt 0 T from DT partial reco DZs agree to < 1 mm Average agreement ~340 mm CMS Hardware-based Muon Alignment 3_5 3_3 3_7 1. 6 mm YB-2 1. 8 mm 3_1 3_9 3_11 2. 3 mm 2. 7 mm LHC Detector Alignment Workshop, June 15 -16, 2009 14

Current CSC Hardware Aligment CMS Side view <Δz. ME+4/1>: 0. 65 mm < x>: Current CSC Hardware Aligment CMS Side view <Δz. ME+4/1>: 0. 65 mm < x>: 1. 9 mrad <Δz. ME+3/1>: -4. 31 mm <Δz. ME+2/1>: -0. 97 mm < x>: 4. 4 mrad <Δz. ME+1/2>: -5. 04 mm <Δz. ME+2/2>: 6. 74 mm ME+4 ME+3 ME+2 CMS Hardware-based Muon Alignment < x>: 4. 4 mrad < x>: 2. 7 mrad <Δz. ME-1/2>: 5. 94 mm <Δz. ME-1/1>: 16. 73 mm < x>: 2. 2 mrad < x>: 1. 6 mrad <Δz. ME-2/1>: 10. 23 mm < x>: 2. 5 mrad <Δz. ME-3/1>: 11. 39 mm < x>: 1. 6 mrad <Δz. ME-4/1>: 8. 49 mm nom. Pink: Aligned by Tracker-Muon Link system Blue: Updated ! Aligned by Muon Endcap optical & analog (Z sensors) System Red: No <Δz. ME+1/3>: <Δz. ME-1/3>: alignment yet 4. 08 mm -4. 08 mm <Δz. ME+3/2>: 3. 26 mm zglobal x = 0 <Δz. ME+1/1>: -17. 57 mm nom. Nominal CSC position rglobal ME+1 ← Muon Endcap stations → ME-1 LHC Detector Alignment Workshop, June 15 -16, 2009 < x>: 2. 2 mrad < x>: 1. 3 mrad B=3. 8 T < x>: 2. 4 mrad < x>: 2. 6 mrad < x>: 2. 7 mrad < x>: 1. 3 mrad Nominal CSC position Not to scale <Δz. ME-2/2>: 2. 74 mm ME-2 <Δz. ME-3/2>: 3. 86 mm ME-3 ME-4 15

Conclusions & Outlook • Achievements – Reconstruct movements/deformations due to magnetic forces • Independent Conclusions & Outlook • Achievements – Reconstruct movements/deformations due to magnetic forces • Independent system measurements show good agreement – First combined Link+Endcap geometry constants • For endcap Cathode Strip Chambers • Used for CRAFT reconstruction – Initial partial geometry reconstruction of barrel Drift Tubes • Outlook – Finish full DT geometry reconstruction – Produce combined hardware DT+CSC geometry • Relate it to tracker frame – Estimate alignment uncertainties • Include alignment+uncertainties into global track reconstruction – Combine with track-based • Take the best of each system CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 16

BACKUP CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 17 BACKUP CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 17

Offline Geometry Reconstruction COCOA: CMS Object-oriented Code for Optical Alignment Geometrical reconstruction based on Offline Geometry Reconstruction COCOA: CMS Object-oriented Code for Optical Alignment Geometrical reconstruction based on iterative non-linear c 2 fit Measurements System Description Interconnection of elements Mechanical hierarchies Initial geometry (Photogrammetry or ideal) Parameters can be fixed, calibrated or unknown Correct parameters iteratively Propagate errors taking into account correlations Best geometrical description compatible with measurements and calibrations Parameter errors and correlations CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 18

BACKUP: Alignment Data Flow online (P 5) offline CMSMON PC (CMS CR) T 0 BACKUP: Alignment Data Flow online (P 5) offline CMSMON PC (CMS CR) T 0 injection script /cms/mon/data/ cocoafiles. root ROOT S 2 G 19 PC CAF ONLINE DB ORACLE PVSS RDB Kvaser POPCON application ORCON DTAlignment. Rcd DTAlignment. Errors. Rcd CSCAlignment. Rcd. CSC Alignment. Errors. Rcd CMS Hardware-based Muon Alignment Tier-0 + CASTOR LHC Detector Alignment Workshop, June 15 -16, 2009 input COCOA output Validation ORCOFF DTAlignment. Rcd DTAlignment. Errors. Rcd CSCAlignment. Rcd. CSC Alignment. Errors. Rcd CMS RECO 19

BACKUP CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 20 BACKUP CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 20

BACKUP CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 21 BACKUP CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 21

AR w. r. t. TK disk 10+ disk 9+ Not drawn to scale! disk AR w. r. t. TK disk 10+ disk 9+ Not drawn to scale! disk 9 - BD+ disk 10 - TK BD- -2956 -2754, 9 -2667, 5 0 2667, 5 AR- 2754, 9 2956 AR+ D = 87, 4 CMS Hardware-based Muon Alignment LHC Detector Alignment Workshop, June 15 -16, 2009 22