Preliminary NML RadiaBeam Transverse Profile Monitor Initial Testing at A0 Alex Lumpkin Bob Flora...

Preliminary

NMLNML RadiaBeam RadiaBeamTransverse Profile Transverse Profile

MonitorMonitor Initial Testing Initial Testing at at A0A0

Alex Lumpkin Bob Flora Congcong Tan James Santucci Jinhao Ruan Randy Thurman-Keup Yin-e Sun

Brad Tennis Elias Lopez Ryan Montiel

Dallas Heikkinen Jim Fitzgerald Jim Galloway John Seraphin

2010 September 29

Bob Goodwin Mike Kucera

Ce:YAGCe:YAG

OTROTR

Virtual Virtual TargetTarget

Zoom Zoom LensLens

CameraCameraActuatorActuator

MirrorsMirrorsFilter Filter WheelWheel

The “A0 RadiaBeam” project objective is to evaluate transverse beam profile monitors proposed for the NML Low Energy Beamlines. A0 was simply chosen as a convenient test bed and RadiaBeam was chosen on the merits of their modular IBIS (Integrated Beam Imaging System) design proposal. Thin metallic foil screens for Optical Transition Radiation (OTR) and Ce:YAG single‐crystal scintillators are being investigated along with all supporting mechanical, electronic, and optical systems. The project goal is to move from prototype evaluation into production for NML.

16 16 lines/mmlines/mm

Reference

Black

WhiteWhite

48%48% modulatiomodulatio

nn

fully zoomed out 18x18 mm field ‐of view, resolution in excess of 15

line pairs per mm(at 20% contrast)

Resolution:Resolution:σ =14 µmσ =14 µm

29 29 lines/mmlines/mm

Reference

Black

WhiteWhite

50%50% modulatiomodulatio

nn

Resolution:Resolution:σ = 7 µmσ = 7 µm

Zoom to 5 mm

Zoom Zoom efficiencefficiency = 58%y = 58%

Virtual Target

15 mm

LEDLED

LEDLED

YAG YAG ScreenScreen

YAG YAG ScreenScreen

CameraCamera

Virtual Virtual TargetTarget

Virtual Virtual TargetTarget

LEDLED

Virtual Virtual TargetTarget

CameraCamera

Z matchedZ matched

First Light

10 bunches on YAG

Bea

mBea

m

Dark

Curr

ent

Dark

Curr

ent

YAG edge

YAG edge

Small Round Beam

242 µm242 µm

100 pC on YAG100 pC on YAG

Narrow Beam Stripe

131 µm131 µm

100 pC on YAG100 pC on YAG

Short Flat Beam

60x96 µm60x96 µm

20 pC on YAG20 pC on YAG

ZOOM

1 mm1 mm197 pix197 pix

oror5.08 µm/pix5.08 µm/pix

Zoom In

46 µm46 µm

Low Charge

We easily measured single

bunch beams less than 15 pC15 pC

with sigma widthsof ~50 µm.

Repeatability (with beam)

• 5 withOUT actuation: ~±2 pixels

• 5 WITH actuation: ~±2 pixels

2 sets of 5 measurements

need to make more

measurements just using the LED illumination

Conclusion

•What we DID measure:• 46 µm46 µm sigma beam

• 15 pC15 pC single bunch

•What we did NOT find:• the YAG saturationsaturation point

• the OTR meltingmelting point

Possible Improvements

• Replace Virtual Target with 4th position Calibration Target• Requires binary weighted actuators• Use annular LED to illuminate Calibration Target or fixed beam splitter with LED

• Zoom lens needs position read back for zoom, aperture, and focus.

• Eliminate bearing over-constraint (use gimbal bearings and relaxed clearance)

• needs to include solenoid & bracket mounted and wired with mounted connector.

• limit switches need to be calibrated and wired with mounted connector

• finger pinch shield needs to be broken up into 3 2π/3 pieces

• foils need to be delivered mounted and pre-baked.

• Vacuum cross and optical assembly need to be joined with a bolted flange.

• must include an integral ridged backbone

• each cross needs to be delivered as a completely assembled & functional package

BergozBergozIn-flange Integrating Current

Transformer

Unfiltered Signal

50 MHz Low Pass

250 MHzDigitizer

62 data points / bunch