us cms doe/nsf review: may 8-10, 20011 endcap alignment dick loveless doe/nsf review 9 may 2001

US CMS DOE/NSF Review: May 8-10, 2001 1

Endcap AlignmentEndcap AlignmentEndcap AlignmentEndcap Alignment

Dick Loveless

DOE/NSF Review

9 May 2001


Progress since Apr ‘00Progress since Apr ‘00Progress since Apr ‘00Progress since Apr ‘00

Mechanical layout

Alignment sensors -- DCOPS• Uses CCDs and a cross-hair laser

ISR Alignment Test - summer ‘00• First realistic test of hardware and software

Engineering Design Review - Nov ‘00• Approval for alignment h/w on chambers

Developments in readout and DAQ

COCOA simulation

Alignment tests in ‘01


Alignment designAlignment designAlignment designAlignment design

CSC alignment• Precise relationship of strips, alignment pins, and

sensors on CSCs• Precise location of sensors on CSCs using internal

calibrations and photogrammetry• Radial measurements from transfer plate to CSCs

by potentiometers

Transfer plate location• Axial lines monitor location wrt tracker co-ords• Z distance measured by mechanical tubes and

optical gap sensors

Cross check using photogrammetry


Layout• Basically finished

• SLM and axial lines integrated into endcap drawings - no conflicts

• Agreement with Link & Barrel groups on interfaces

Drawings • Most drawings finished, need some minor changes

to match the sensor design

• Z tube drawings not finished

• Still need a MAB design (CERN responsibility)

Mechanical ProgressMechanical ProgressMechanical ProgressMechanical Progress


SLM profile viewSLM profile viewSLM profile viewSLM profile view


Sensor technologySensor technologySensor technologySensor technologyDesign requirement for our system

• Many (up to 10) sensors in a line must all be capable of locating the laser beam

• Present transparent sensors are not transparent enough and projected developments do not match our schedule

Design “standard tech” sensor• Develop design using conventional items (relatively low risk)• 4 linear CCDs mounted in a window frame• Cross-hair laser beam• Readout with DSP processor and serial I/O • Digital CCD optical position sensor (DCOPS)


DCOPS sensor boxDCOPS sensor boxDCOPS sensor boxDCOPS sensor box

•64mm x 64mm Al box with black anodizing

•4 CCD arrays mounted at right angles to laser

•Red wedge filters on face of CCDs - bidirectional

•Standard mounting configuration


DCOPS Test PlansDCOPS Test PlansDCOPS Test PlansDCOPS Test Plans

Goal• Develop final DCOPS by end of ‘01• Understand calibration requirements and techniques

Prototypes• Building 25 prototype DCOPS sensors • Fermilab is setting up an SLM line with DCOPS• Northeastern will test calibration procedures

Realistic testing• Reliability of components (red filters, ND filters,

electronics, etc.)• DAQ system• Reconstruction algorithms


June - Sept 2000 at CERN ISR Tunnel

Goal : • Setup and monitor “chambers” with resolution of < 200 m• Demonstrate System RedundancyTest Setup :• 1 SLM Line (2 Laser Redundancy)• 1 Transfer Line (Single Laser)• 1 Transfer Plate• Analog Sensors (Temp, Proximity)

ISR Prototype System TestISR Prototype System Test ISR Prototype System TestISR Prototype System Test


ISR Prototype System TestISR Prototype System TestISR Prototype System TestISR Prototype System Test

Data Analysis :• 1500+ Events Reconstructed• 3 Test Periods (July, Aug, Sept 2000)New Analysis Software :• Prototype Reconstruction Software Used• CMS Object oriented Code for Optical Alignment

(COCOA)

Our Expectations :

• Laser Position or Direction Will Not Matter

• Only Small Fluctuations in ISR System


ISR Test LayoutISR Test LayoutISR Test LayoutISR Test Layout


ISR Test GeometryISR Test GeometryISR Test GeometryISR Test Geometry

• Sensor locations for et2, et3, and es10 are given by the photogrammetry survey

• es9 was used due to survey errors in es10

• Transfer plate geometry was fixed by machining

• Sensors et1 and es1 were located on the transfer plate

• Provides link between Transfer and SLM lines

• Rotations of sensors are known within error limits of photogrammetry


ISR Test ReconstructionISR Test ReconstructionISR Test ReconstructionISR Test ReconstructionTitle:

Creator:ROOT Version2.24/04Preview:This EPS picture was not savedwith a preview included in it.Comment:This EPS picture will print to aPostScript printer, but not toother types of printers.

Final ISR Results of COCOA reconstruction for July/August and September runs using es9 as the final reference sensor


Comments on ISR TestComments on ISR TestComments on ISR TestComments on ISR Test

Reconstruction Dominated By Survey Errors• Estimated Survey Errors

• 60 m local 120 m global• Errors in COCOA Reconstruction

• 220 m Systematic Errors < 15 m Statistical Errors (1500 Events)

General Remarks • Good reconstruction requires all 4 CCDs on MABS and Transfer

Plate SLM sensors• 3 CCDs required for all other sensors• Reconstruction is roughly independent of laser direction• Reconstruction is independent of laser motions

• Laser ‘Jumps’ Do Not Affect Us


ISR ResultsISR ResultsISR ResultsISR Results

Final Results :• System = 130 m

• Typical Reconstructions within 300 m of expected survey location

• Sensors outside 300 m range have understood errors


Eng. Design Rev -- Nov ‘00Eng. Design Rev -- Nov ‘00Eng. Design Rev -- Nov ‘00Eng. Design Rev -- Nov ‘00

1) Endorse the general muon alignment scheme

2) Request the Muon Alignment group to participate to the CMS Working Group that will define the 3 region including tubes reserved for the alignment system and laser boxes for the Link system.

3) Schedule an Electronic Systems Review (ESR) for the three systems (BMU, EMU, & Link) at the same time.

4) Make sure the alignment system can be run at zero field and nominal field.

5) Fix milestones for the selection of the 2D sensors in line with muon chamber manufacturing schedules.

6) Reorganize MAB project to make sure procurement can proceed at very beginning of 2002.

7) Proceed with the procurement of sensors and mounts to be attached to the muon chambers (BMU & EMU) together with the associated cameras.

The committee recommends to:


Alignment tests ‘01Alignment tests ‘01Alignment tests ‘01Alignment tests ‘01

SLM - Fermilab• Construct a compete SLM line using 10 new

DCOPS sensors

• Verify filtering and attenuation designs

• Check out aperture solutions

• Develop final version of readout boards and services

• Program DSP to calculate the centroid for each sensor

• Develop final version of DAQ system (linux)

• Develop final version of COCOA reconstruction program


Action items ‘01Action items ‘01Action items ‘01Action items ‘01

DCOPS Calibration• Test procedures and reliability

Production plans• Quality assurance documentation• Responsibility• Calibration database• Radiation testing of components

Slow Control interface• Databases• Hardware• Software

Integration with CSC chambers - space/noise


Design ProblemDesign ProblemDesign ProblemDesign Problem

Magnetic field operation• We need to operate the alignment system in both

field-on and field-off modes

• Disks will deflect when field is on, possibly by 15mm

• DCOPS apertures are 25mm at best

• There may not be a line of sight good for both field-on and field-off operation

Must find a solution


InstallationInstallationInstallationInstallation

Components installed at CERN• Island plates glued on just prior to CSC

installation, begin in Oct ‘02

• SLM lines (mounts, towers, transfer plates) installed after CSC station is complete, expect 1st station ready for alignment in spring ‘03

• Services (power, readout lines, etc.) tested for each station

• After station is complete we do photogrammetry

• Axial components installed on each disk in SX5, some testing may be possible

• Axial lines complete only in UX5


COCOA Simulation GoalsCOCOA Simulation GoalsCOCOA Simulation GoalsCOCOA Simulation Goals

Create Model CMS EMU Alignment System• DCOPS + Analog Sensors

• Integrate with Link and Barrel alignment

Evaluate Intrinsic System Errors• Chamber construction

• System design

Evaluate System Performance• Intrinsic Resolution

• Correlation of System Components

• Effects from component failure

Provide ‘First Draft’ of Reconstruction Software

Integration of Results into General Physics Simulation


Current Status (May 2001)• Substantial Software Improvements• Extraction of Component Data from Endcap Muon

Production Drawings (Complete)

• SLM Lines and Endcap CSC Stations have been modeled

COCOA SimulationCOCOA SimulationCOCOA SimulationCOCOA Simulation

ME2/3/4 COCOA ModelSimulated COCOA SLM Line


ConclusionConclusionConclusionConclusion

Alignment system making reasonable progress toward a good design

• Still many tasks to complete

• Group is small but dedicated

Next Eng. Design Rev• Scheduled for end of ‘01

• Design must be final

• Production plans must be ready

us cms doe/nsf review: may 8-10, 20011 endcap alignment dick loveless doe/nsf review 9 may 2001

Documents