University of Wisconsin-Madison Cocoa ME+1 James N. Bellinger University of Wisconsin-Madison 18-Feb-2009

How close are we? Coded targets tell where chamber surface is Hand calculation minus coded target Poor agreement Hand est- PG z ME+1/3/03 -7.76 ME+1/3/09 -3.70 ME+1/3/14 -3.68 ME+1/3/20 -4.77 ME+1/3/27 -2.09 ME+1/3/33 7.57 (bad) James N. Bellinger 18-Feb-2009

ME+1/2 Outer layout Chamber Surface Target=3mm SensorBox = 63mm dowel Sensor mount plate =10mm Shim: 12.1mm outer, (4.6mm inner) Mount plate = 6.35mm DCOPS Spacer = 35mm Chamber frame plate: 6mm Chamber Surface For upper Target top=reference Frame = ref- 135.45 Sensor center = ref-26 (=23+3) DCOPS center = ref- 135.726 Surface = DCOPS center+0.276 DCOPS dowel = ref-94.45 41.276mm dowel to center James N. Bellinger 18-Feb-2009

ME+1/3 layout DCOPS Chamber Surface DCOPS center to dowel: 41.276mm Mount plate: 6.35mm Spacer: 25mm Chamber frame plate: 6mm Chamber Surface James N. Bellinger 18-Feb-2009

Is something missing? Original Cocoa number for +1/3 DCOPS to chamber surface seems to be wrong The descriptions of the material involved in the DCOPS and ASPD mounting for the HSLM are laid out in in tree form in http://www.hep.wisc.edu/~jnb/cms/docs/psl/MEp1.html The chamber frame information is from Wenman and I don’t have the construction drawings defining it. James N. Bellinger 18-Feb-2009

Doing my own optimization Use Link info to get ASPD top for ME+1/2 outer and the distancemeter position for the Transfer Plate Use offsets from CAD drawings to reach DCOPS center positions Include profile positions (not at center) and calculate a line joining the two points Predict profile position at ME+1/3 DCOPS Use profile positions and CAD information to predict chamber surface positions James N. Bellinger 18-Feb-2009

Optimizing Use the average of these two surface positions as an estimate of the surface at 0T Subtract the coded target position (on surface), square and form a chi-squared Sum for HSLM1-5 only: HSLM6 known bad Variables: X=additional distance between ASPD and DCOPS at ME+1/2 Y=additional distance between DCOPS and surface at ME+1/3 James N. Bellinger 18-Feb-2009

X variable definition X Chamber Surface Target=3mm SensorBox = 63mm dowel Sensor mount plate =10mm Shim: 12.1mm outer, (4.6mm inner) Mount plate = 6.35mm X Spacer = 35mm DCOPS Frame plate: 6mm Chamber Surface For upper Target top=reference Frame = ref- 135.45 Sensor center = ref-26 (=23+3) DCOPS center = ref- 135.726 Surface = DCOPS center+0.276 DCOPS dowel = ref-94.45 41.276mm dowel to center James N. Bellinger 18-Feb-2009

Y variable definiton DCOPS Y Chamber Surface DCOPS center to dowel: 41.276mm Mount plate: 6.35mm Spacer: 25mm Y Frame plate: 6mm Chamber Surface James N. Bellinger 18-Feb-2009

Result 4.411X + 10Y = 44.172 If X=0 (ME+1/2 mount known perfectly) Need 4.42mm extra between DCOPS and ME+1/3 surface If Y=0 (ME+1/3 mount known perfectly) Need 9.00mm extra between ASPD PG4 and DCOPS center. James N. Bellinger 18-Feb-2009

Is the ASPD position wrong? But Photographs show the ASPD mounting, and it matches my understanding from the CAD drawings Xiaofeng assures me he mounted the DCOPS directly under the mounting plate No room for 9mm spacers at ASPD Is the ASPD position wrong? No. Celso finds agreement between PG and his P4 reference calculation And.. James N. Bellinger 18-Feb-2009

ASPD P4 to chamber surface ME+1/2 has coded targets also Compare Cocoa 0T fit to coded target locations in Z Suggests ASPD to surface is understood and OK Cocoa-PG ME+1/2/02 0.16 ME+1/2/08 2.45 ME+1/2/14 0.25 ME+1/2/20 -0.62 ME+1/2/26 0.65 ME+1/2/32 7.57 (bad) James N. Bellinger 18-Feb-2009

Transfer Plate? Trying the same trick with the Transfer Plate suggests that the DCOPS center is 8.7mm farther to the rear than I calculate from drawings AFFLp-15.00.00BLK etc James N. Bellinger 18-Feb-2009

This afternoon Redo model of line using PG points as reference instead of Link system references Note that some of the PG alignment pin measurements are inconsistent with each other. Fortunately we usually have the coded targets on the chamber surface to cross- reference with, and let us decide which to discard James N. Bellinger 18-Feb-2009