1 / 31

Status of the Muon Alignment System

Status of the Muon Alignment System. Muon Alignment Group. Muon IB December 11th, 2012. Outline. Status of the Track-based Alignment Status of the Upgrade on the Hardware-based Barrel Alignment Issue with the Hardware-based EndCap Alignment. Overview.

myra-snyder
Télécharger la présentation

Status of the Muon Alignment System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Status of the MuonAlignment System Muon Alignment Group Muon IB December 11th, 2012

  2. Outline • Status of theTrack-basedAlignment • Status of the Upgrade ontheHardware-based Barrel Alignment • IssuewiththeHardware-basedEndCapAlignment Zoltán Szillási (ATOMKI)Muon IB, November 29th, 2011

  3. Overview • CMS tracking alignment workflow • Update Tracker geometry  • recently released with 2012 A+B data • Update Muon Global Position Record (GPR)  • optimum position of Muon system based on reconstruction performance • Update Muon geometry with new Tracker and new GPR  • run track-based algorithm over 2012 A+B data • Muon Geometry was updated in November 2012 • DT and CSC chambers aligned with respect to Tracker using track-based algorithm with 2012 A+B collision data • slight performance improvement in Barrel (DTs were already aligned with tracks from 2011 collision data) • significant performance improvement in Endcaps (this is first time individual CSCs are fully aligned with tracks) Muon IB Meeting, 11 December 2012

  4. Muon Reconstruction Performance • Resolution: • Slight (5% for RMS) improvement in Barrel • DTs aligned well with 2011 data • Significant improvement in Endcaps • CSCs individually aligned with tracks Endcaps | Muon IB Meeting, 11 December 2012

  5. Dimuon mass at peak • Resolution of dimuon mass reconstruction at Z-peak • STA+STA muons are used • Barrel – no changes • Endcaps – improves Muon IB Meeting, 11 December 2012

  6. Summary • New Muon geometry produced and validated • New Tracker geometry and new GPR are used • Latest CMSSW and 2012 A+B data are used • New Muon geometry is validated • Significant improvement in Endcaps • this is first time individual CSCs are fully aligned with tracks • The new Muon geometry was signed off • New Muon geometry is in Data Base and being validated with all other updated conditions • Exact description and recipe how to use new Muon alignment and GPR were announced in AlCaDBhypernews on Nov 27, 2012 06:57 • https://hypernews.cern.ch/HyperNews/CMS/get/calibrations/1273.html Muon IB Meeting, 11 December 2012

  7. Plans • Produce new MC scenario matching new Muon geometry • Study systematic uncertainties and include them in APEs • Superlayers misalignment • Compare updated geometry to latest HW geometry • check twist effect • Repeat Muon alignment workflow including 2012 C data • following Tracker geometry update Muon IB Meeting, 11 December 2012

  8. HW Barrel Ali Plansin LS1 • ie. As soon as a wheel opens, we have to remove all MABs and transport them to the Alignment Lab • In the lab: new targets and calibrations (both for Barrel and Link) • In the lab: store the MABs safely • Meanwhile in UXC: repositioning the BoardPC and recabling in the shadow of other activities • MABs are to be re-installed at the end of other activities right before wheel closed • PHOTOGRAMMETRY!!! It takes several hours (~ d/wheel). On MABs we will need everywhere, but will need on chambers that moved, too. • AR will be removed before the arrival of the new beampipe and be reinstalled when ready – PG needed! Alignment goes first and returns the last! Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  9. Reinforcement of measurements in Sector 13 & 14 • The reconstruction error for rotZ of MB4 twin chambers are higher than the other MB4 chambers.Reason: those chambers can seen only from one side • Solution: install “Mini MAB” to those chambers. Very similar to the MAB, but it houses only 2 camera. • The proposed positions are seen on the drawing below. Due to several reasons (blocking electronic and cooling cables) it is impossible to put Mini MAB to every twin chamber. • Results of simulation calculation of errors are on the tables. The position calculations shows the worst case, where the chamber can be seen though two other chamber. • With the Mini MABs the alignment precision for these chambers will be better. Mini MAB Sector 13 Sector 4 Cameras identical to those used for chimney-chamber regions d Proposed MiniMAB arrangement: YB+2 YB+1 YB0 YB-1 YB-2 S4 X Results of simulation S13 MAB Carbon-fiber plate (5mm thickness) MiniMAB S10 Sector 10 Sector 14 S14 Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  10. CMS barrel part duringinstallation Location of the miniMAB (see next page) Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  11. MiniMABlocation The miniMAB plate is fixed on rails of the muon chambers (drilling new threaded holes not needed) The cameras are looking into these passages Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  12. MiniMABs Short MiniMAB / Long MiniMAB • The base material of the MiniMAB is glassfiber (yellow) • The fixation of MiniMAB is not shown in this plan Gábor Endrőczi Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  13. Additional photogrammetry targets/redesign photogrammetry targets on MABs • Motivation: • There was a discrepancy between the track-based and the hardware alignments both in Z (2mm, scaling?) and phi-like torsion (3mm) • So far we have only indirect ways to test where it comes from • Torsion has gone, but was not solved by muon hardware alignment! We need a direct external measurement possibility. • What to do? • Install additional photogrammetry target to MABs • These targets are viewable for photogrammetry measurements, when the detector is already closed. • Only those targets are measurable, which are marked with solid line. There is a slight chance to measure those target which are marked with dashed line. Impossible to make photogrammetry measurements in those places which are not marked. • How? • Survey group could measure Z coordinates of them (or at least Z distance) • Precision is around 70 microns (discrepancy, we had ~ 2mm!) • Maybe they can measure phi position as well ? answer for torsion… • If Z-scaling found, its value can be used as a correction later. Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  14. Map of Survey points in UXC • 2011 September TS --­­ Visual inspection has been done on the possibility on the MAB visibility and mounting of new Survey brackets on the UXC wall • 2011 December (at B=0) final position of brackets were measured (planned to have some installation, but didn’t happen) Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  15. Viewable MABs are for Survey measurements Green – measurable Orange – difficult to measure, but not impossible -3/3 -1/3 -2/4 -2/2 -3/5 -1/5 -3/1 -1/1 YB+1 YB-1 YB-2 YB0 - YB0 + -2/6 -212 -3/7 -3/11 -1/7 -1/11 -2/10 -2/8 -3/9 -1/9 +3/3 +1/3 +2/4 +2/2 +3/5 +1/5 +3/1 +1/1 YB+2 +2/6 +212 +3/7 +3/11 +1/7 +1/11 +2/10 +2/8 • Total Barrel length measurement at Sectors 1,5,11 • Partial Barrel length measurement at Sectors 8,11 +3/9 +1/9 Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  16. Finalprototype of the Survey Target holder Finalprototypeready. Manufacturing of thelarge batch is ontheway Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  17. Evacuation of BoardPC from the gaps • The BoardPC placed between the gaps of the CMS barrel wheels in order to be close to the MABs. • These PCs control some part of LEDs and digitalize and analyze the images of the cameras of MABs • They are unreachable when the CMS wheels are closed. CMS barrel wheels was open last time in the beginning of 2008 and they are not expected to be open more frequently after LS1. • After the failures of image grabbers cards of some BoardPCs, we started to think about to evacuate them to the side of the YBs(we had 3 at the beginning, now we have 7). • The possible places to install the BoardPCs has been checkedDuring 2011 November TS. Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  18. BoardPC repositioning – draft plan Far Near Passive wheel (YB±1) Passive MABs (±2/x) Active wheel (YB±2 & YB0) Active MABs (±3/x & ±1/x) X5 X5 Place of BoardPC Probably better place for the BoardPC X4 X4 Extra: X2 Near A3006 PS modules  X4 (YB±1) X3 X3 X2 X2 X1 X1 Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  19. MABsreached Nearside: YB0 – MAB ±1/11 YB±1 – MAB ±2/10 YB±2 – MAB ±3/11 Far side: YB0 – MAB ±1/9 YB±1 – MAB ±2/8 YB±2 – MAB ±3/9 BoardPC repositioning – X1 Place of BoardPC MAB in the gap Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  20. MABsreached Nearside: YB0 – MAB ±1/1 YB±1 – MAB ±2/12 YB±2 – MAB ±3/1 Far side: YB0 – MAB ±1/7 YB±1 – MAB ±2/6 YB±2 – MAB ±3/7 BoardPC repositioning – X3 Passive MAB Active MAB Place of BoardPC Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  21. MABsreached Nearside: YB0 – MAB ±1/3 YB±1 – MAB ±2/2 YB±2 – MAB ±3/3 Far side: YB0 – MAB ±1/5 YB±1 – MAB ±2/4 YB±2 – MAB ±3/5 BoardPC repositioning – X5 Place of BoardPC in YB±1 & ±2 Place of BoardPC in YB0 Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  22. Status of the Upgrade • Reinforcement of measurements in Sector 13 & 14 • design has been done– proto in weeks; offer arrived • Mimmoproposestomountthemonthechamberrails, design of MiniMAB fixation will come soon • necessary Caen 3006 PS already purchased • Additional PG targets/redesign PG targets on MABs • holder prototype ready; order already sent out • survey of the external viewing possibilities done • next: starting to mount external Survey brackets for external Wheels • waiting for offer on targets (Antje) • Bringing out BoardPCs from the gaps • long cable check in ISR done, result positive • waiting for Mimmo to measure cable length (needed for the cable order) • Mimmo needs to finalize the new BoardPC places Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  23. Long-term upgrade plans • Eliminate the single failure point caused by the single frame grabber card on the BoardPCs by changing the cameras to digital. Beside bringing the digitization to the individual cameras, this would allow parallel processing of data and better noise tolerance between the camera and the BoardPC. • We also wondering on changing the BoardPCs themselves since the technology will be more than 10 years old by then and the spare part supply will probably either impossible or unmaintainably expensive. LS2 idea (not yet a proposal. First let’s get through LS1  ): Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  24. Issuewiththe HW EndCapAligment System (Hubert Gerwig, TIG, 2012.10.04) TransferPlate is inconflictwithME4! • No more manpowerforanalysison ME • Transfer line mighthelpinunderstandingthe Barrel systematics • Barrel is willingtoparticipateinanalysis, provided: • Wecanunderstandthependingcalibrationissues • Unfortunately, wedon’t haveresourcesforredesign + modify Is theconclusionclear? Zoltán Szillási (ATOMKI) Muon IB, November 29th, 2011

  25. Back Up Yuriy Pakhotin (Texas A&M) Muon IB, November 29th, 2011

  26. Current Muon Alignment • Current Muon geometry was signed off in February 2011 • Barrel alignment • DT chambers aligned with respect to Tracker using 2011 collision data and track-based algorithm • Tracker and Muon System relative alignment implemented as Global Position Record • only tracks in Barrel used, but Endcap and Barrel globally aligned • Endcap alignment • CSC chambers aligned with respect to each other using CSC overlaps algorithm with beam halo data collected in 2010 with several photogrammetry and SLM constraints • muons from collisions used to cross check result with beam-halo, same result within precision • Endcap Rings aligned w.r.t. Tracker as rigid bodies • global movement and rotation in plane perpendicular to beam line Yuriy Pakhotin (Texas A&M) Muon IB, November 29th, 2011

  27. Updated Muon Alignment Workflow Conditions • Software release: CMSSW_5_3_6_patch1 • Data Sample (2012 A+B re-reco): • /SingleMu/Run2012A-MuAlCalIsolatedMu-13Jul2012-v1/ALCARECO • /SingleMu/Run2012B-MuAlCalIsolatedMu-13Jul2012-v1/ALCARECO • Input Tracker geometry: • frontier://FrontierProd/CMS_COND_31X_ALIGNMENT • TrackerAlignment_v9a_offline • frontier://FrontierProd/CMS_COND_31X_ALIGNMENT • TrackerAlignmentErrors_v3_offline • frontier://FrontierProd/CMS_COND_310X_ALIGN • TrackerSurfaceDeformations_v3_offline • Input GPR and Muon geometry: • This is starting geometry for Muon alignment iterative algorithm • New GPR obtained with current Muon geometry and new Tracker • Current Muon geometry from Global Tag GR_R_53_V16A • fully track-based Muon alignment signed off on March 2nd 2012 Updated tracker Yuriy Pakhotin (Texas A&M) AlCaDB Meeting, 27 November 2012

  28. Muon Tracks Selection • Refit reconstructed global muons • new Tracker geometry and new GPR used • Select only “good” tracks to use for alignment • transverse momentum: • impact parameter w.r.t. beam spot position: • number of hits in Tracker segment: • normalized for Tracker segment: • Propagate selected tracks to Muon system • number of chambers (DT or CSC) with hits per track: • number of hits per aligned chamber: • in CSC: • in DT in Super Layers 1 and 3: • in DT in Super Layer 2: Yuriy Pakhotin (Texas A&M) AlCaDB Meeting, 27 November 2012

  29. Muon Residuals • Muon residual is difference between measured (with hits) and predicted (i.e. propagated from Tracker) position of the muon in the chamber • Residuals calculated in chamber’s local frame • local residual x = track local x – hit local x • scattering in iron  width of residual distribution • chamber misalignment  non-zero mean of distribution Yuriy Pakhotin (Texas A&M) AlCaDB Meeting, 27 November 2012

  30. Residuals and aligned coordinates • Angle-displacement correlations for tracks are not used • For DT: use and residuals, align local , and • For CSC: use residuals, align local and • NOTE: Muon chambers aligned independently Yuriy Pakhotin (Texas A&M) AlCaDB Meeting, 27 November 2012

  31. DT Superlayer Misalignment • Superlayer profiles example before and after δφzSL1&3 corrections in a problematic chamber: • Slopes of superlayers become very close plot from VadimKhotilovich (Texas A&M) plot from VadimKhotilovich (Texas A&M) Yuriy Pakhotin (Texas A&M) Muon IB, November 29th, 2011

More Related