# Presentation: 765566

## Synclite status

- -or-
*“**Hey, where did all the light go?”*

- R. Thurman-Keup

## Instrumentation related artifacts

- All done without filters
- # of camera frames
- MCP voltage vs. Duty cycle
- Attenuator
- Pulser voltage
- 2-D scan of intensifier/camera (check intensity and sigma)
- Few percent variation

- R. Thurman-Keup

## Gain vs. MCP voltage

- Skipped turns = 43

- R. Thurman-Keup

## Sigma vs. number of camera frames

- R. Thurman-Keup

## Sigma vs. ( skipped turns, a.k.a. inverse duty cycle, and MCP voltage )

- R. Thurman-Keup

## Sigma vs. ( skipped turns, a.k.a. inverse duty cycle, and MCP voltage )

- MCP Voltage

- Skipped Turns (inverse duty cycle)

- R. Thurman-Keup

## Sigma vs. input light intensity

- R. Thurman-Keup

## Sigma vs. image intensifier pulsing voltage

- R. Thurman-Keup

## Gain linearity with photon flux

- R. Thurman-Keup

## Mirror Moves

- Discovered that the proton mirror had been inadvertently moved in by half an inch over the shutdown
- Source of the large tails seen earlier
- Moved the proton mirror back out a ways, but not quite as far out as it was.  Should move it back to where it was.
- Moved the pbar mirror in to record images.

- R. Thurman-Keup

## Before / after mirror move at 440 nm

- R. Thurman-Keup

## Protons

- R. Thurman-Keup

## Antiprotons

- R. Thurman-Keup

## Simulation is a numerical integration of synchrotron light equations.  Result is a wavefront that can be propagated further through optical elements.  In our case a lens and various apertures simulating the pickoff mirror.  Propagation is via ??? Equation which includes diffractive effects.  

- R. Thurman-Keup

## Proton mirror move simulation with varying optical configurations

- Nominal

- Light at center of lens

- Out of focus (too close)

- Out of focus (too far)

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## Effect of clipping the edge light with beampipe (modeled by aperture)

- Nominal

- Just starting to clip

- Roughly 1/3 clipping

- Roughly 2/3 clipping

- R. Thurman-Keup

## Antiproton Data

- R. Thurman-Keup

## Antiproton Simulation

- Camera focused ~1 meter into body of magnet

- R. Thurman-Keup

## Protons

- Looking along beamline....

- Beampipe Radius 32 mm
- Separation  from beam 26 mm
- Light cone radius 5 mm

- Dipole

- 6.1 m

- Beampipe Radius 37 mm
- Separation from beam 34 mm
- Light cone radius 6 mm

- Beampipe Radius 50 mm
- Separation from beam 36 mm
- Light cone radius 6 mm

- 1.15 m

- 0.25 m

- Mirror

- 8 mr from
- vertical

- ~28 mm

- 36 mm

- ~10 mm

- 25 mm radius lens
- occupies the side
- of a 3” pipe

- Light is very close to beampipe

- Light spot

- ~240 mm

- Synchrotron Light

- R. Thurman-Keup

## Antiprotons

- Dipole

- 3 m

- Mirror

- No danger of hitting beampipe

- Separation from beam is 13 mm
- Light cone radius 4 mm

- Half Dipole

- 8 mm

- 4 mr from
- vertical

- 25 mm radius lens

- ~300 mm

- Synchrotron Light

- 0.14 m

- 1.6 m

- 50 mm beampipe radius

- 37 mm beampipe radius

- 32 mm beampipe radius

- 7 mm

- R. Thurman-Keup

## Diffraction

- Measure the width at different wavelengths
- Diffraction ~ λ
- Sigma = Sigma(beam) + Diffraction
- Sigma = sqrt( σ2 + λ2 )
- Check that the focal point vs. wavelength makes sense

- R. Thurman-Keup

## Slide 22

- R. Thurman-Keup

## Slide 23

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## Plano-convex lens, BK7, (R is radius)

- Refractive Index, *n*

- Plano-convex lens, BK7, (*R* is radius)

- R. Thurman-Keup

## Camera

- Notice split in peaks

- Edge light

- Body light

- Beam

- Lens

- R. Thurman-Keup

## Conclusions

- The horse is not dead yet
- Extract diffraction contributions for p and pbar, hor. and vert.
- Check pbar shapes (probably end up being better behaved than proton)
- Missing light
- Move the proton mirror in finer steps to determine horizontal distribution of light
- Move the beam (off helix?)
- Continue with simulation in attempt to understand what we see

- R. Thurman-Keup

## Store 3745

- FBI ratio is 10;  SL ratio is 0.3;  expected SL ratio (beam splitter, mirror) is 4.5
- actual p / expected p ~ 0.07.   Only 7% of light getting through???

- R. Thurman-Keup

## Slide 28

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## Slide 29

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## Slide 30

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## Beampipe cutoff

- Unobstructed intensity

- Mirror

- Distance from cutoff to edge of mirror

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## Protons

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## Antiprotons

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## Slide 34

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## Ratio of pbar to proton = 4

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## Antiproton Images

- Early in store

**Antiproton Images**

- Late in store

-  = 26 hrs

- R. Thurman-Keup

## Synclite Horizontal  

- Synclite Horizontal 

- Synclite Vertical 

- Synclite Hor. Emittance

- Synclite Vert. Emittance

- FW Vert. Emittance

- FW Hor. Emittance

- Emittance Fix

- R. Thurman-Keup

## Second Intensity study of effect on sigma (pbar mirror out)

- This calculation of raw amplitude is wrong!!!

- R. Thurman-Keup

## Second Intensity study of effect on sigma (pbar mirror out)

- R. Thurman-Keup

## Third Intensity study of effect on sigma (pbar mirror in)

- Note:  This plot is a quadrature measurement of distortion, not d****/****

- Correction is subtracted in quadrature from sigmas.
- Curve is     9.524x10-6 * I2 + 9.524x10-4 * I

- R. Thurman-Keup

## Slide 41

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## Higher intensity light pulse

- Lower intensity light pulse

- Blue is low intensity
- Dark red is high intensity

*Roughly factor of two difference in intensity between two plots.  Note shift in peak at higher intensity.  *

- R. Thurman-Keup

## Slide 43

- R. Thurman-Keup

## Setting the camera focal point

- R. Thurman-Keup

## Synclight status

- In conclusion...
- Put in correction to sigma for intensity
- Moved cameras to “focal point”?
- Received repaired camera
- Will check it out and get the others repaired
- Install in pbar
- Found smoking gun for 4 times gain of pbars
- Emittances are now as good as we can get?
- Need to compare with FW over the next week
- Diffraction is  ~  240m hor. 130m ver.

- R. Thurman-Keup

## Slide 46

- R. Thurman-Keup