Collider Run II - Doing Shots

1. Collider Run II - Doing Shots Elvin Harms Fermilab Antiproton Source Harms@fnal.gov X4387

2. What’s a Shot? • Transferring Antiprotons from the Accumulator to the Tevatron. Ops – Intro to Shots

3. What’s Shot set up ? • All of the preparatory steps needed to do shots. Ops – Intro to Shots

4. Accelerator Complex Overview Proton source Antiproton source Tevatron Main Injector Recycler Ops – Intro to Shots

5. Accelerator Complex Overview Proton source Tevatron Antiproton source AP3 MI-8 AP1 A1 P2 Main Injector Recycler P1 Ops – Intro to Shots

6. Shot set-up – prerequisites • Previous Store ended • Tevatron at 150 GeV (fringe fields on P1 & P2) • Desired number of antiprotons accumulated Ops – Intro to Shots

7. Shot set-up – a 3-ring circus Ops – Intro to Shots

8. Shot set-up – Pbar basic steps • Stop stacking • Cool core • Tune up P1, P2, AP1, AP3 at 8 GeV with Reverse protons • Minimize betatron oscillations in Accumulator • Redistribute core • Unstack and extract 4 bunches nine times • Return to stacking Ops – Intro to Shots

9. Shot set-up – Sequencer • 6 aggregates • Promotes reproducibility • Automates much of process • Flexible • ‘Pbar Back-up’ for now Ops – Intro to Shots

10. Shot set-up – Antiproton source tools • Core cooling • RF systems • ARF1, h = 84, – matching to MI • ARF2, h = 2, – stability, squaring • ARF4, h = 4, – unstacking Ops – Intro to Shots

11. Sequencer – Start Shot Set Up • arm SDA • set up alarms • AP1 from 120 to 8 GeV • AP3 on • Reverse proton TLG • Prompts for MI,P1 -> AP3 tune up • maintain core stability • tranverse emittances • longitudinally Ops – Intro to Shots

12. Reverse Proton tune up – P143 User-friendly version being developed Start Shot set-up Ops – Intro to Shots

13. Minimize Accumulator Turn-by-Turn oscillations – P140 Start Shot set-up Ops – Intro to Shots

14. Sequencer – Set Up… • TLG for Pbars loaded • 4-8 GHz core momentum cooling on • cw ARF2 on • A:EKIK timing for pbars Ops – Intro to Shots

15. Test shots without beam RF systems play except for unstacking amplitude Verify phase lock Verify timing Verify kicker magnets are working Sequencer – ‘Dry’ Shots Ops – Intro to Shots

16. Set up ARF2 to shake the core Frequency-modulated 1.25 MHz RF – set interactively Unstack uniform intensity bunches Sequencer – Square Core… Ops – Intro to Shots

17. Squaring the Core • ‘square’ core allows uniform intensity of pbar bunches Ops – Intro to Shots

18. Sequencer – Run II Unstacking… • Cooling off • Shutters open • ARF4 set for to unstack • Clock events enabled/disabled for transfer • Unstack/transfer to MI • Cooling back on and wait Ops – Intro to Shots

19. Unstacking Timing • TCLK $91 to unstack • TCLK $9A prepare to transfer • MIBS $7A (plus delay) to transfer Ops – Intro to Shots

20. Unstacking • 2.5 MHz (h=4) RF system – ARF4 • 4 bunches at a time • low initial voltage • increase voltage to narrow bunches • lock to MI RF • bunch at 53 MHz (h=84) • extract • ~30 seconds per transfer Ops – Intro to Shots

21. Unstacking & Extraction • Re-bunch at 53 MHz on extraction orbit • Shuttered fast kicker magnet (1.6ms) Ops – Intro to Shots

22. Doing Shots • Transfer to MI • Acceleration to 150 GeV • coalescing Ops – Intro to Shots

23. Doing Shots • Coalescing • 4-53 MHz bunch trains into 4-2.5 MHz bunches Ops – Intro to Shots

24. Sequencer - Return to Stacking • Close out SDA • Re-cool beam into core • Set up alarms for stacking • Timing reset for stacking • AP3 off • AP1 set to 120 GeV • RF systems and diagnostics reset for stacking Ops – Intro to Shots

25. Important Tools • Sequencer • Time Line Generator (TLG) • Dedicated Applications • CDA/SDA Ops – Intro to Shots

26. Unique Applications • P140 – VSA TBT • P142 – VSA Acc Long Prof • P143 – APX. Lattice (Beam line tuner) • P185 – Emittance Calc • P186 – AP0 Scope Ops – Intro to Shots

27. Important Tools • Sequencer • ACNET application • Automates much of the process • Flexible • Interactive Ops – Intro to Shots

28. Important Tools • Time Line Generator (TLG) • central Beam switching system • who gets what beam when and how often • different Timelines for different modes • Shot set up • Load protons • Load pbars Ops – Intro to Shots

29. Important Tools • Dedicated Applications • Beam line tuning • Orbit display and control • RF and stochastic cooling systems • Diagnostic display • Parameter pages Ops – Intro to Shots

30. Important Tools • CDA/SDA • Gather, display, and analyze data from shots • State-based • Java applications Ops – Intro to Shots

31. Armchair Shooter • How to watch? • Channel 13/Notify • Pbar TV channel 7 – AP1 wall current monitor • Pbar TV channel 15 – Accumulator Vector Signal Analyzer • Pbar TV channel 16 – Accumulator unstacking display • Pbar TV channel 18 – Accumulator Vector Signal Analyzer • Pbar TV channel 28 – Accumulator Stack (longitudinal) Profile Ops – Intro to Shots

32. Summary • Tools are in place for Run II operation • Refinement still in progress • We’re still learning how to do shots • Work with us! Ops – Intro to Shots