Qweak Installation

Information for installing the R1 chambers into Hall C

Installation Dates

Date	Milestone
Planned (11/08)	Completed
11/25/09		Qweak Install begins with Qtor
3/18/10		Install Rotator
3/31/10		install Region 1 Chamber
4/21/10		Survey Region 1 Chamber
7/22/10		Qweak Commission
11/23/10		Qweak Run 1
4/11/11		Qweak Run 2

Definitions

Survey tolorance

The accuracy in the absolute location of an object

Alignment Tolerance

The accuracy of an object relative some other known object.

"Would like to"

desired alignment accuracy

"Must have"

Required alignment accuracy

"Known to"

desired survey accuracy

Tolorances

The charge collector strips are less than 0.4 mm wide. The concentric strips can give you a direct measurement of the electron scattering angle [math]\theta[/math] if they are properly alignment with the beam line.

The numbers below are just a Guess with no justification from a simulation or hand calculation.

Tolorance for GEM relative to the PRIMARY COLLIMATOR (2nd collimator)

Survey can pretend to do 50 micron resolution 200 micron resolution is no problem.

Survey marker tooling balls need 1/4 inch rods to mount prisms on. Should have at least 3, 1/4 holes on detector.

Coordinate	"Would like to"	"Must have"	Known to
	(mm)	(mm)	(mm)
X	0.05	0.2	0.2
Y	0.05	0.2	0.2
Z	1	10	1
Yaw(about Y)
Pitch (about X)
Roll(about Z)	[math]\infty[/math]	[math]\infty[/math]	[math]\infty[/math]

Survey marker locations

The coordinates given below are with respect to an arbitrary reference point identified by the cross hairs just below the label "B".

Point	Design (x, y)(mm)	Hall-C (x', y') (mm)
A	5.025; 60	7; 0
B	16.4858; 26.485	18.45658; -33.515
C	88.497; 3.492	90.477; -56.508
D	246.999; -18	248.979; -78
E	295.005; 60	296.985; 0
F	246.991; 138	248.971; 78
G	88.500; 116.493	90.48; 56.493
H	16.493; 93.488	18.473; 33.488

Chamber Gases

Region II and III wil use gas mixture:

% Volume	Gas
88	Argon
10	CO2
2	Methane

Cables

JLAB supplies

4 SHV cables from GEM Rotator to Counting House

2 RJ45 cables to GEM gumsticks located in dog house front of target

4 BNC Coax cables from GEM detector to Alena's scintillator coincidence NIM modules located near quartz detector

4 120 Volt power lines to dog house

2 120 Volt power lines to GEM rotator

cable from G0 32 MHz clock to V1495 in the dog house

coax cable from Alena's coincidence NIM modules to V1495 doghouse location

LaTech supplies

4 ribbon cables from V1495 in Doghouse to breakout box on rotator

2 RJ45 I2C cables from dog house upstream of target to breakout box on GEM rotator

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