1

Mike and Brianna

Polarimeter update

2

Old design of internal elements

3

Converter tray (position: retracted)

Tray allows up to 4 converters

Mounting plate

4

Converter tray (position: 1)

• Tray 1: wire

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Converter tray (position: 2)

• Tray 2: beryllium 35 μm

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Converter tray (position: 3)

• Tray 3: beryllium 70 μm

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Converter tray (position: 4)

• Tray 4: thin carbon

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With optical limit switches

• Transfer Engineering

optical switch

• Vacuum rated down to

10-11 Torr

Will use different

limit switches

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Motor • Manufacturer: Phytron

• Vacuum rated to 7.5 x 10-12 torr

• Radiation resistant to 106 J/kg (~3x1018 MeV over

lifetime of ½ kg motor)

• Holding torque: 33 oz-in

• Cost: $5756 (with resolver, and resolver-encoder

converter)

42 mm 69 mm 16 mm 15 mm

Mass = 0.52 kg

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With motor

Note: The teeth on the

gear and rack are not

shown

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With motor mount

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With rack guide

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With rack guide supports

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With detector supports

Building test rail with guide

15

• Made miniature rail and guide to

test our basic design and

machining capabilities

• Note: mock up of rail does not

have teeth

• Actual rail we have ordered

Final result

Relative placement of position

system components

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• Motor shown is not the one

that will be used in the

vacuum

• Vacuum rated motor is

about twice as long, but

other dimensions are the

same

• Do not see any conflicts in

the placement of elements

Other developments

17

• Finished the power distribution box design

• Still waiting on Methanol (for cleaning chamber surfaces)

• Attached KF-25 fittings to VisiTrap

• Power poles have arrived

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Distribution box: front

• The front of the distribution box supplies voltages to the preamps

• Four preamps and each has a +12 V and -12 V input

• One of the preamps will have a high voltage input

Holes for mounting screws

SMA

SMA

BNC

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Distribution box: right side

SHV

high voltage input

Ethernet

to

Arduino

USB

to

Arduino

D-sub connector

from chamber

(motor controls

and limit switches)

FAN: Right

Red: +12V

Green: Ground

Yellow: Tachometer

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Distribution box: left side

D-sub connector

pass-through

to outside world

FAN: Left

Red: +12V

Green: Ground

Yellow: Tachometer

Low voltage in

Red: +12V

Black: -12V

Green: Ground

Purple: Sense wire (+12 V)

Blue: Sense wire (-12 V)

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Next

• As parts come in we continue to build!