1 / 23

PEP-II Overall Plans

PEP-II Overall Plans. John Seeman for the PEP-II Team Particle and Particle-Astrophysics Directorate Stanford Linear Accelerator Center PEP-II MAC Meeting November 15, 2007. Topics. PEP-II MAC meeting information Charge to the MAC Committee MAC agenda and talks:

kale
Download Presentation

PEP-II Overall Plans

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PEP-II Overall Plans John Seeman for the PEP-II Team Particle and Particle-Astrophysics Directorate Stanford Linear Accelerator Center PEP-II MAC Meeting November 15, 2007

  2. Topics • PEP-II MAC meeting information • Charge to the MAC Committee • MAC agenda and talks: http://www.slac.stanford.edu/grp/ad/pep-ii/MAC-Review/MAC-Nov2007/ • Highlights of Run 6. • Main activities for Fall 2007 down • Plan for Run 7 in FY2008 • Shut down planning

  3. PEP-II MAC Information • In an emergency: • Fire: Leave the building by the nearest safe exit • Earthquake: Duck, cover, then leave the building • Others: Best to leave the building; meet outside • Meeting Rooms: • Thursday am: Kavli Auditorium (Kavli) • All the rest: Redwood Room (ROB) • Dinner Thursday evening (7 pm) • Logan Davis or Regina Matter will have maps.

  4. Charge • The combined team of PEP-II and BaBar has amassed a large data set in the past nine years, reaching a total of 500 fb-1. To keep the experiment viable, this team needs to reach a total of about 750 fb-1 in the next 10 months (50% more). This requires increasing the performance in a commensurate way. • With regard to the PEP-II facility, the Laboratory is requesting the Machine Advisory Committee (MAC) to: • a) Critique the plans for maximizing the integrated luminosity in Run 7 which goes from December 2007 through September 2008. • b) Appraise the luminosity improvement plans to reach the peak luminosity goal in the spring of 2008. • c) Review the near-term focus and schedule for accelerator physics studies as they contribute to maximizing the integral for Run 7.

  5. The PEP-II Team Accelerator Systems Division SLAC Support Groups BaBar Machine Advisory Committee 1x1034

  6. The PEP-II Team • Run Coordinator: M. Sullivan • Beam dynamics: F-J. Decker, S. Heifets, A. Kulikov, U. Wienands • IR: S. Ecklund, W. Wittmer, M. Weaver • Lattice: Y. Cai, Y. Yan, G. Yocky, M. H. Wang • RF: A. Hill, H. Schwarz, D. Van Winkle, V. Pacak, K. Bertsche • HOM: A. Novokhatski, S. Weathersby, K. Ng • Feedback: J. Fox, A. Young, R. Akre • Instrumentation: A. Fisher, M. Petree, W. Cheng, M. Browne, R. Chestnut • Vacuum: S. DeBarger, M. Dormiani, D. Kharakh, N. Kurita, S. Metcalfe, R. Pope, N. Reeck • Systems: M. Zurawel, P. Smith, K. Burrows, T. Graul, T. Galetto, A. Baker • Operations: Operators, R. Erickson, M. Stanek, P. Schuh, W. Colocho, B. Allen • Much appreciated help from: Power Conversion, Software, Controls, CEF, Metrology, Klystron, Radiation Physics, Beam Physics, BaBar

  7. Run 6 New Advances for PEP-II • Two new HER RF stations in, working and are ready for higher currents. • New skew quad fix for IR2 LER x-y coupling found and implemented. Specific luminosity is higher. More luminosity gain is expected in the future. (Decker, …) • Fast dither IP feedback in and working with supervision (Sullivan, Fisher, …). • Vertical vibration in IR support tube damped with BaBar’s help. Thanks.

  8. Run 6 January-September 2007 Major Problems • Late start from the Fall 2006 down • Vacuum leak in HER IR Q4 chamber • Damaged coils on IR Quadrupole Q2 • Bunch Injection Controller problems occurred . New system was installed. • VAT seal near luminosity chamber leaked. • HER flex-flange seals show discharges • More PG&E AC power dips than normal.

  9. HER arc 5 RF seal at 6122

  10. August 2007 was our Best month New month and 30 day records

  11. PEP-II Parameter Goals have not changed! 4 times design 7 times design

  12. Fall 2007 Down Activities (September 4-December 3) • Finish LER BPM replacement. (Done) • Add 5 HER Arc HOM bellows. (To start soon) • Add 12 LER IR2 HOM bellows. (To start soon) • Replace about 192 HER Arc flex-flange RF “Omega Seals”. (5/6 done) • Install two new LER Q5 chambers in IR2. (Done) • Install repaired HER Q4L chamber. (Done)

  13. New HOM absorbers work and more are being built. Novokhatski Weathersby Kurita Reeck Absorbing tiles

  14. General Overall Plan for Run 7 (Dec 2007-Sept 2008) • Start the linac and PEP-II in December. • Run through the holidays. • Do more machine studies (MD) early to increase luminosity at the beginning of the run. • Keep in any new accelerator configuration with a luminosity improvement and then keep running! • Find the optimum luminosity condition by early spring. • Run through September with best steady state conditions.

  15. Proposed Run Plan December-March • In general collide for BaBar as much as possible! • December goals: • Scrub both rings while colliding. • Reestablish 0.8x1034 parameters. • Holiday running (minimal supervision) • January-March goals: • Establish 1.7x1034 parameters. • Establish HER 90 degree lattice. • LER lower vertical emittance using IR skew quads • Increase HER/LER RF voltages. • Try lowering by*s in collision. • Increase beam currents

  16. Proposed April-September Plan • Goals: ~April 1 start a steady state run. • Collide for BaBar constantly. • Establish 1.7 to 2.0 x 1034 parameters gradually. • No MDs except for tuning during collisions or for very good possibilities.

  17. Luminosity Projection • We make luminosity projections using: • Known running months • Past running efficiencies (~55% with many MDs and ~68% with a few MDs) • Expected gains in peak luminosity (1.22.0x 1034) • Known downtimes

  18. Sept 5, 2007 PEP-II projected luminosity spreadsheet

  19. Now

  20. PEP-II Shut Down • PEP-II will stop producing data for BaBar on September 30, 2008, about ten months from now. • PEP-II and BaBar will then transition rapidly into a “Minimal Maintenance State (MMS)” which takes just over a year. • In the medium time frame, PEP-II will be at this MMS with some effort going into tunnel maintenance, safety lighting, electrical safety and mechanical safety. Valuable items will be preserved. • For long term, D&D of PEP-II is being studied. A DOE review held in early August 6-7, 2007.

  21. Conclusions PEP-II accelerator in Run 6 was more difficult than planned but the run ended well. The luminosity will be ramped as fast as possible in Run 7. PEP-II will integrate as much luminosity as possible. Execution of the Fall 2007 shut down is going well. Upgrades towards ~21034 will soon be done with the aim of 257 fb-1 more to 757 fb-1. PEP-II will turn off September 30, 2008.

More Related