Intensity Measurements through the Stacking Cycle

1. Intensity Measurements through the Stacking Cycle Recycler/Pbar Beam Physics Meeting Keith Gollwitzer January 14, 2005

2. What Intensities? • Currently ~5x1012 protons on target. • Secondaries in AP2 and early in the Debuncher ~109 particles • Circulating in Debuncher and transferred to Accumulator is ~7.5x107 pbars • Accumulator core increases up to ~1.5x1012 pbars

3. Different Measurements • One pass • Toroids (Dave P.) • SEMs relative measurements; blows up beam • Ion Chamber small blow up of beam • Gap Monitor INJFLX; first pass in Debuncher • Circulating in Debuncher • BPM Intensity require bunch/debunch during stacking cycle • DCCT (Dave P.) • FFT prior to extraction Longitudinal coherence • Circulating in Accumulator • FFT on injection orbit Longitudinal coherence • BPM Intensity for free during ARF1 ramp • Deposition orbit new stacktail monitor

4. One Pass Measurements During Stacking Toroid SEM Ion Chamber Gap Monitor (INJFLX) Solid – Existing Dashed – Future Dotted – Not Stack DtoA Transfer

5. SEM Intensity measurement from area of fit Shown here is special Debuncher SEM403. Two vertical peaks are the injection pass and closed orbit. Beam is completely killed by multiple closed orbit passes. Dependent upon being able to subtract noise Wires intercept beam and cause beam blow-up

6. Different Measurements • One pass • Toroids (Dave P.) • SEMs relative measurements; blows up beam • Ion Chamber small blow up of beam • Gap Monitor INJFLX; first pass in Debuncher • Circulating in Debuncher • BPM Intensity require bunch/debunch during stacking cycle • DCCT (Dave P.) • FFT prior to extraction Longitudinal coherence • Circulating in Accumulator • FFT on injection orbit Longitudinal coherence • BPM Intensity for free during ARF1 ramp • Deposition orbit new stacktail monitor

7. Flux capacitor (INJFLX) from mixing the gap monitor with the RF signal Being updated to be a java OAC. Overhead seems to limit to 3-4sec per update; being worked upon.

8. Different Measurements • One pass • Toroids (Dave P.) • SEMs relative measurements; blows up beam • Ion Chamber small blow up of beam • Gap Monitor INJFLX; first pass in Debuncher • Circulating in Debuncher • BPM Intensity require bunch/debunch during stacking cycle • DCCT (Dave P.) • FFT prior to extraction Longitudinal coherence • Circulating in Accumulator • FFT on injection orbit Longitudinal coherence • BPM Intensity for free during ARF1 ramp • Deposition orbit new stacktail monitor

9. Beam Injection Beam Extraction Sample BPM during 20ms flat top Sample time for ACNET DAQ DRF1 bunching pbars prior to the end of the stacking cycle in the Debunchers P2 curve design ; time is with respect to $80

10. Switching plate BPM signal sent through a SA at zero span and small resolution bandwidth (averaging) and its video output sent to an oscilloscope input triggered via D:TBT ($83) Blow-up time scale and pull trace of “flat-top” signal and process height for ACNET variable Bunch and Debunch beam for intensity sampling Injection of secondaries and debunching Not the same P2 curve as previous slide In the future, SA and scope setup will be replaced by Ashmanskas board

11. Simple comparison of Intensities BPM Intensity (arb) IC728 (10^8 secondaries) TOR109 (10^12 protons)

12. BPM Intensity BPM / TOR109 IC728 / TOR109 BPM / IC728 Histogramming of Intensities ~3% Width

13. Different Measurements • One pass • Toroids (Dave P.) • SEMs relative measurements; blows up beam • Ion Chamber small blow up of beam • Gap Monitor INJFLX; first pass in Debuncher • Circulating in Debuncher • BPM Intensity require bunch/debunch during stacking cycle • DCCT (Dave P.) • FFT prior to extraction Longitudinal coherence • Circulating in Accumulator • FFT on injection orbit Longitudinal coherence • BPM Intensity for free during ARF1 ramp • Deposition orbit new stacktail monitor

14. Recent Changes to FFT 1st look at “stability” Previous version had averaging and history involved. Coherence would affect signal for awhile. Also saw periodic behavior. Now trying to place in OAC Averaging but no history. Coherence – What to do Paul Derwent is investigating Accumulator Debuncher

15. Different Measurements • One pass • Toroids (Dave P.) • SEMs relative measurements; blows up beam • Ion Chamber small blow up of beam • Gap Monitor INJFLX; first pass in Debuncher • Circulating in Debuncher • BPM Intensity require bunch/debunch during stacking cycle • DCCT (Dave P.) • FFT prior to extraction Longitudinal coherence • Circulating in Accumulator • FFT on injection orbit Longitudinal coherence • BPM Intensity for free during ARF1 ramp • Deposition orbit new stacktail monitor

16. New Stacktail Monitor • Main purpose is to watch deposition area and monitor how efficiently the stacktail system clears the deposition orbit area (the width of ARF1 bucket). • Essentially measures power prior and after ARF1 deposits beam. • Can use as relative measure of beam on deposition orbit(?) To be Seen.

17. Comment about Events & Timeline • It has been noticed that the “stability” of intensity signals during stacking is dependent upon Event and Timeline • There can be a yield difference between pure $29 slip stacking events and $21 mixed mode stacking + switchyard event: up to 10% for IC728/TOR109 • The TLG does not make it easy for consistent $80 spacing; in general stacking cycle time varies. • One shots and other study cycles