1 / 25

James N. Bellinger University of Wisconsin-Madison 6-December-2009

Transfer Line and CSC R φ Reconstruction. James N. Bellinger University of Wisconsin-Madison 6-December-2009. James N. Bellinger 6-December-2009. Data. Most of the Transfer Line lasers are well aligned. The best illuminated is Line 1, and the worst is Line 2 The following shows Line 1

jmagdalena
Télécharger la présentation

James N. Bellinger University of Wisconsin-Madison 6-December-2009

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. Transfer Line and CSC Rφ Reconstruction James N. Bellinger University of Wisconsin-Madison 6-December-2009 James N. Bellinger 6-December-2009

  2. James N. Bellinger 6-December-2009 Data • Most of the Transfer Line lasers are well aligned. • The best illuminated is Line 1, and the worst is Line 2 • The following shows Line 1 • All data used in this report is 3.8T from an event in October • One DCOPS reading failed and was replaced with another from a run 8 hours earlier

  3. James N. Bellinger 6-December-2009 DCOPS along Transfer Lines Mounted on MABs Minus Endcap Plus Endcap CMS Z

  4. James N. Bellinger 6-December-2009 Transfer Lines: Positions 2 6 Transfer Lines of 12 DCOPS Lasers at ME+4 and ME-4 shine axially Establish relative X,Y of the transfer plates, and thus the SLM ends 3 SLM example 1 4 Y 6 X 5

  5. James N. Bellinger 6-December-2009 DCOPS Sensors with Laser A crosshair laser (a pair of lasers each shining through a cylindrical lens) illuminates each of the DCOPS in turn along the line DCOPS Laser

  6. James N. Bellinger 6-December-2009 Transfer Line DCOPS • Up/Down CCDs measure Rphi, either in positive or negative direction depending on the DCOPS orientation • Left/Right CCDs measure radial positions • Transfer Lines are independent of each other UP CCD RIGHT CCD LEFT CCD DOWN CCD Radius direction

  7. James N. Bellinger 6-December-2009 Purpose of Transfer Lines • Outer MAB positions are defined by Link wrt the tracker body • Using Outer MAB positions to define lines in space, determine where the Transfer Plates are in space • Using Transfer Plate positions determine the positions of the measured Endcap chambers • Determine an outer position on the Inner MABs as a cross-check for the Barrel

  8. James N. Bellinger 6-December-2009 Transfer Line 1, Laser 1 Laser Plus Endcap MABs Minus Endcap CCD 1 and 3 are top two rows. They measure Rphi CCD 2 and 4 are bottom two rows. They measure R The red curve is the fit to the profile At each station (column) at least one profile within each pair is good

  9. James N. Bellinger 6-December-2009 Transfer Line 1, Laser 2 Laser Plus Endcap MABs Minus Endcap CCD 1 and 3 are top two rows. They measure Rphi CCD 2 and 4 are bottom two rows. They measure R The red curve is the fit to the profile At each station (column) at least one profile within each pair is good

  10. Photogrammetry and Drawings • PG measured the disk centers • PG measured the Transfer DCOPS position wrt. the disk center • The relative position of points on the Transfer Plates was taken from drawings James N. Bellinger 6-December-2009

  11. Locating the Transfer Line • Link can give the outer MAB positions in (x,y,z) wrt a tracker body reference • PG gives us an estimate of Z for the Endcaps • Still working on Z-sensor reconstruction • Combining these can give us (x,y,z) for measured chambers James N. Bellinger 6-December-2009

  12. Simple Use of the Transfer Line • The Link information gives us fixed points in space (in principle 12) to tie the 6 Transfer Lines to the tracker. With lines fixed in space we can use averages of Transfer Line positions on each disk to estimate disk rotations James N. Bellinger 6-December-2009

  13. James N. Bellinger 6-December-2009 Radial Fits From Cocoa Yellow lines locate DCOPS apertures Notice that the hit and fit to the hit are close. The fits are good. How good? Plus laser Minus laser Green circles are measured hits Red diamonds are fit hits Error bars are too small to see

  14. James N. Bellinger 6-December-2009 Summary of Fit Residuals Left/Right CCDs are illuminated by one pair of laser fans, and Up/Down CCDs are illuminated by the other pair. I look at them separately here. In Transfer Line 3 one of the lasers is not perfectly aligned, and in 2 both sets need adjustment. The next slide plots both types of CCD residuals together. Oleg finds 110µ with extra data quality cuts

  15. James N. Bellinger 6-December-2009 Laser Fit Residuals for Line 1 Tight central core of well- measured points: 120 µ Scattering of less good points. Core fit agrees with Oleg RMS=490 µ Measured-Fit in mm

  16. James N. Bellinger 6-December-2009 CCD Measurement Consistency • If neither of a pair of CCDs is shadowed, they provide independent measurements of the laser position at that point, subject to • Tilting of the transfer plate • expected to be small • Tilt of the laser fan itself • measured in Cocoa, ignored here • Variation in CCD position within the DCOPS • of order 100 µ RMS

  17. James N. Bellinger 6-December-2009 Compare RAW CCD measurements for Line 1 CCD1-CCD3 or CCD2-CCD4 if both in a pair have good profiles. Only 28 of 48 do, the rest have one side shadowed. RMS =310 µ includes laser tilt and calibration variation! Difference between CCD measurements, mm

  18. James N. Bellinger 6-December-2009 Disk rotations • Averaging the reconstructed DCOPS centers on each disk gives me rotations of the disks. • Knowing MAB positions wrt tracker means these should be real rotations

  19. James N. Bellinger 6-December-2009 Disk rotation results Independent measurements of the same disks. YB+2 and YB-2 MAB positions are the references.

  20. James N. Bellinger 6-December-2009 Chamber Positions • We generated ZCMS positions and YLocal rotations for all CSC for CRAFT09 data • Himali has been studying XCMS /YCMS CSC positions • Machinery is in place to generate positions for measured CSC once we validate the Transfer Line reconstructions with PG σ=159µ The rest are similar

  21. James N. Bellinger 6-December-2009 ME-4 SLM1 Chamber RφShifts with Field Off/On Animated GIF Will not work in PDF Average Shift=20µ Relative CMS Rφ (mm) Plots from Himali

  22. James N. Bellinger 6-December-2009 Summary • The positions of the Transfer Plates are reconstructed to within about 500µ for most lines. We think we can do better. • Ready to reconstruct chamber positions as soon as group approves Transfer Plate positioning • Transfer Line 2 laser tweaking will improve the data

  23. James N. Bellinger 6-December-2009 BACKUP MATERIAL

  24. James N. Bellinger 6-December-2009 Transfer Line 2, Laser 1 (worst) Profile shape is odd No connection to far station Harmless glitch: I used data from earlier event here

  25. James N. Bellinger 6-December-2009 Transfer Line 2, Laser 2 No connection to U/D for two farthest stations

More Related