FETS Pepperpot
Simon Jolly10th February 2010
The Pepperpot• Beam segmented by
intercepting screen with regular array of holes.
• Beamlets drift short distance before producing image on scintillator screen.
• Support block prevents beamlets from overlapping and provides cooling.
• CCD camera records image of light spots.
• Calculate emittance from spot distribution.
10/02/10 Simon Jolly, Imperial College 2
Incoming Beam
Intercepting screen
Support block
Scintillator screen
Beamlets
Fast CCD Camera
FETS Pepperpot Design
10/02/10 Simon Jolly, Imperial College 3
Vacuum bellows
Camera
Moving rod
Shutter
Mounting flange
Pepperpot head
Bellows
Tungsten mesh
Beam profile head
Pepperpot and Slit-Slit Scanners
10/02/10 Simon Jolly, Imperial College 4
Calibration System• Need to produce 4 light
spots on scintillator screen for calibration.
• Bring in 4 optical fibres through spare holes in copper mounting block.
• Fibre stops a little way short of scintillator screen, mounted in centre of 2mm x 13mm glass dowel.
• Glass dowel is frosted on scintillator screen end.
• Light from fibre produces 1mm spot on frosted end of glass dowel ie. at scintillator screen.
• Spots are imaged for calibration.
10/02/10 Simon Jolly, Imperial College 5
Scintillator screen
Copper mounting block
Fast CCD Camera
To light source
Pepperpot Head
10/02/10 Simon Jolly, Imperial College 6
FETS pepperpot uses tungsten intercepting screen with 50 micron holes on 3 mm pitch, 10 mm drift and quartz scintillator.
Pepperpot Head: Mounting Holes
10/02/10 Simon Jolly, Imperial College 7
FETS pepperpot uses tungsten intercepting screen with 50 micron holes on 3 mm pitch, 10 mm drift and quartz scintillator.Tungsten screen and copper mounting blocks are aligned with 4 2mm x 13mm metal dowels.
Pepperpot Head: Calibration Holes
10/02/10 Simon Jolly, Imperial College 8
FETS pepperpot uses tungsten intercepting screen with 50 micron holes on 3 mm pitch, 10 mm drift and quartz scintillator.Tungsten screen and copper mounting blocks are aligned with 4 2mm x 13mm metal dowels.
4 spare 2mm dowel holes to be used for fibre optic calibration
Fibres come in from back side of head.
Pepperpot Support & Main Flange
10/02/10 Simon Jolly, Imperial College 9
The linear shift mechanism (LSML) from UHVDesign mounted to the main flange.
Adjustable camera mount.
Cooled feed through rod.
KF-40 vacuum flanges used for feedthroughs
Pepperpot Mounted to Vacuum Tank
10/02/10 Simon Jolly, Imperial College 10
KF-40 flange to be used for fibre optic feedthrough.
