Status of the Barrel Alignment –

Comparision of 0T–3.8T movement to Survey

This project is supported by the Hungarian National Research Fund (OTKA) No.: NK67974

Bencze György, Béni Noémi, Szillási Zoltán, Ujvári Balázs

(ATOMKI, RMKI, University of Debrecen)

(on behalf of the Barrel Alignment group)

Muon Barrel Workshop, 2011.05.05.

2011.05.05. 2

• Presentation of the Survey results on target moving between 0T and 3.8T

• Calculation of Survey targets’ drift from reconstructed MAB positions

• Calculation of Survey targets’ drift from Z-bar measurements

• Comparision of results

Outline:

• We know from previous studies (see Barrel report on 2010 Aug Barrel WS) PG is recovered from Barrel reco at 0T

• 3.8T PG is not possible We want to see whether relative movements are beliveable or not…

Motivation:

ΔZ MEASURED BY THE SURVEY GROUP

2011.05.05. 3

Measurement of the Survey Group

4

Measurement of the Survey Group

5

Measurement of the Survey Group

6

Measurement of the Survey Group

7

First order model for 0T 3.8T

2011.05.05. 8

P P’ P”

Assume no deformationsin Zglobal

)sin(),( fitobj

ntranslatio R

RAZRZ

fit by thegiven parameters :,,

fitin objects of radius average)(:

fitntranslatio

obj

AZ

R

Objects (MABs, Z-bars) define planes.

Plane movement can be fitted over object ΔZ.

ΔZ BASED ON RECONSTRUCTION OF THE MABS

2011.05.05. 9

Gap -3

102011.05.05.

Gap -2

112011.05.05.

Gap -1

122011.05.05.

Gap +1

132011.05.05.

Gap +2

142011.05.05.

Gap +3

152011.05.05.

Fit parameters

2011.05.05. 16

Gap ΔZtranslation A φfit

-3 1,7 -0,47 0,49

-2 1 0,28 4

-1 -0,042 -0,056 -0,12

+1 0,075 -0,12 -0.13

+2 -1,1 0,46 1,5

+3 -1,7 0,55 0,91

MABs for wheel +/- 2

2011.05.05. 17

Near side Far side

DZ [mm] DZ [mm]

Calculated to survey position

SurveyCalculated to survey position

Survey

YB-2 1 2,638226458 3,6

YB-2

2,151049997 3

YB-2 2 2,638201875 3,6 2,15108667 3

YB-2 BC 2,622194261 3,9 2,063044264 3

Avg 2,632874198 3,7 2,121726977 3

YB+2 1 -2,705395167 -2,3

YB+2

-1,730380193 -2,3

YB+2 2 -2,70536284 -2,3 -1,7303424 -2,3

YB+2 BC -2,734807869 -2,4 -1,615142019 -2,6

avg -2,715188625 -2,33333 -1,69195487 -2,4

982.144.4542

97.9003

mab

survey

obj R

R

R

R

MABs for wheel +/- 1

2011.05.05. 18

Near side Far side

DZ [mm] DZ [mm]

Calculated to survey position

SurveyCalculated to survey position

Survey

YB-1 1 1,558789558 0,4

YB-1

1,076178643 0,2

YB-1 2 1,558827354 0,3 1,076201761 0,1

YB-1 BC 1,572187976 0,6 1,017896415 0,2

Avg 1,563268296 0,433333 1,05675894 0,166667

YB+1 1 -1,708817669 -0,9

YB+1

-0,69237305 0

YB+1 2 -1,709184033 -0,9 -0,692288965 -0,3

YB+1 BC -1,780205631 -0,9 -0,613077562 -0,2

avg -1,732735778 -0,9 -0,665913192 -0,16667

982.144.4542

97.9003

mab

survey

obj R

R

R

R

ΔZ BASED ON Z-BAR MEASUREMENTS

2011.05.05. 19

Z-bar measurements on YB±2

ZLED1

ZLED2

ZLED3

ZLED4

ZLED5

ZLED6

IP

ZLED1

ZLED2

ZLED3

ZLED4

ZLED5

ZLED6

Camera local X

Cam

era

local Y

+φCMS

on posZ side+φCMS

on negZ side +ΔX -ΔX -ΔY

YB+2

+Δφ -Δφ to IP

YB-2 -Δφ +Δφ to IP

+

+YB moves (with MAB) instead of Zfork(changes sign in φ, but not in Z due to an other trafo.)

What camera observes:‘Real’ life:

p.20

Z-bar Gap-3

212011.05.05.

Z-bar Gap+3

222011.05.05.

Fit parameters

2011.05.05. 23

Gap ΔZtranslation A φfit

-3 1,9 -0,76 0,01

+3 -1,8 0,44 0,67

174.2646.4140

97.9003

barz

survey

obj R

R

R

R

Z-bar

2011.05.05. 24

Near side Far side

DZ [mm] DZ [mm]

Calculated to survey position

SurveyCalculated to survey position

Survey

YB-2 1 3,28664716 3,6

YB-2

3,30591252 3

YB-2 2 3,28642578 3,6 3,30595325 3

YB-2 BC 3,18062808 3,9 3,20332695 3

Avg 3,25123367 3,7 3,27173091 3

YB+2 1 -2,7928608 -2,3

YB+2

-2,1310475 -2,3

YB+2 2 -2,7928546 -2,3 -2,1310162 -2,3

YB+2 BC -2,7945946 -2,4 -2,0342285 -2,6

avg -2,7934367 -2,33333 -2,098764 -2,4

2011.05.05. 25

Comparision

Comparision of Survey results to the calculated Survey points

Errors:Survey: ±0.5 mmMABs : ±800x√2/ √6 ~ ±0.5mmZ-bar : ~ ±0.5mm

Z-bars and MABs are very much compatible with Survey (except passive MABs on YB ±1 Near

Conclusions

2011.05.05. 26

• Comparision of relative movement of Survey targets to reco’d MABs and Z-bars done

• Z-bars are in complete accordance to the Survey results

• MABs are in accordance to Survey results

• Analyis on chamber data is still to be done

• ΔYglobal movements will be determined from chamber data

• we are working on to constrain MAB/DT reco with Z-bars data (not easy, though!)