1. From Local to Global Weiren Chou For the CEPC-SPPC Study Group Beijing-Chicago Workshop Sept 14–15, 2015, Beijing, China 1 W. ChouBeijing-Chicago Workshop, Sept 14-15, 2015

2. World HEP Accelerators Tevatron LHC BEPC KEKB CEPC-SppC ILC

3. CEPC-SPPC Timeline (preliminary) 3CEPC-SPPC Meeting, May 17-18, 2015W. Chou 20152020202520302035 R&D Engineering Design (2016-2020) Construction (2021-2027) Data taking (2028-2035) Pre-studies (2013-2015) 1 st Milestone: Pre-CDR (by the end of 2014) CEPC 202020302040 R&D (2014-2030) Engineering Design (2030-2035) Construction (2035-2042) Data taking (2042-2055) SPPC 2 nd Milestone: R&D funding in the government’s new 5-year plan (2016-2020)

4. 4 CEPC-SPPC Pre-CDR (March 2015) W. ChouBeijing-Chicago Workshop, Sept 14-15, 2015

5. 5 CEPC-SPPC Pre-CDR (Civil Construction) W. ChouBeijing-Chicago Workshop, Sept 14-15, 2015

6. 6

7. 7 300 authors from 57 institutions in 9 countries W. Chou Beijing-Chicago Workshop, Sept 14-15, 2015

8. Table of Contents (328 pages) 8

9. CEPC Design – Top Level Parameters 9 ParameterDesign Goal Particlese+, e- Center of mass energy240 GeV Integrated luminosity (per IP per year)250 fb -1 No. of IPs2 SPPC Design – Top Level Parameters 9 ParameterDesign Goal Particlesp, p Center of mass energy70 TeV Integrated luminosity (per IP per year)(TBD) No. of IPs2 W. ChouCEPC-SPPC Review, Feb 14-16, 2015 one million Higgs from 2 IPs in 10 years

10. CEPC Lattice Layout (September 24, 2014) P.S. IP1 IP4 IP3 IP2 D = 17.3 km ½ RF RF ½ RF RF One RF station: 650 MHz five-cell SRF cavities; 4 cavities/module 12 modules, 10 m each RF length 120 m 4 IPs, 1038.4 m (944 m) each 4 straights, 849.6 m (944 m) each 8 arcs, 5852.8 m each C = 54.374 km 10

11. Tunnel Cross Section – SPPC + CEPC Magnets 11 Drill/Blast Method 6 m SPPC CEPC Booster

12. 12 Civil Construction Design

13. Status of the Collaboration 13 Collaboration is critical for CEPC-SPPC, more so than any other large project, because the Chinese team is very young and needs a steep learning curve in order to meet the challenging project timeline Invitation to Individual visitors International machine review committee Joint workshops and meetings At this moment, there is no formal collaboration on CEPC between IHEP and other institutions. The MOU with U. of Chicago would be the first one. W. Chou Beijing-Chicago Workshop, Sept 14-15, 2015

14. W. ChouEPS-HEP 201514 Top R&D Items e+e- collider (CEPC and FCC-ee) 1.Power consumption reduction 2.Heat load in the cold region (HOM heating) 3.Dynamic aperture 4.Machine-detector interface (MDI) 5.Pretzel / Partial double-ring (CEPC only) 6.Low energy (6 GeV) injection into the Booster (CEPC only) 7.Specific for Super Z (large number of bunches, polarization, crossing angle, very large HOM loss, etc.) pp collider (FCC-hh and SPPC): 1.SC magnet 2.Heat load in the cold region (SR heating) 3.Machine protection (collimation)

15. 2014 Visitors (27 person-times) 15

16. W. ChouBeijing-Chicago Workshop, Sept 14-15, 201516

17. Mini-Review Reports (13 reports, 28 pages) 17

18. 18 International Review Committee (Feb 14-16, 2015) Committee’s response to the charges: Committee wrote a 17-page detailed report. W. Chou Beijing-Chicago Workshop, Sept 14-15, 2015

19. 19 Jointly organized by the FCC team at CERN and the CEPC- SPPC team at IHEP

20. 20

21. 21 100 TeV pp Collider Workshop (Aug 2014, Fermilab)

22. 22 IAS Workshop on CEPC (Jan 2015, Hong Kong)

23. 23 Aspen Winter Conference (Jan 2015, Aspen)

24. 24 An Important Topic – the pp Luminosity B. Richter, RAST, volume 7, p.1 (2014) Different opinions expressed at numerous meetings: Fermilab workshop, ICFA Seminar, Hong Kong workshop, Aspen Winter Conference, … Active participants include: F. Gianotti, M. Peskin, J. Ellis, L. Evans, C. Young, etc. A paper (arXiv:1504.06108) by: I. Hinchliffe, A. Kotwal, M. Mangano, C. Quigg, L. Wang

25. 25 Workshop on SC Magnets (Jun 2015, Shanghai)

26. pp R&D #1 – SC Magnets Tevatron (p-pbar) HERA (p-e) RHIC (ion-ion) LHC (p-p) 26 All cosine theta, all NbTi

27. (courtesy of Peter Lee, Applied SC Center of FSU) 27 An Important Topic – Superconductors 32.20 Tesla SC magnet R&D – the cost driver and most important R&D for SPPC

28. W. Chou Beijing-Chicago Workshop, Sept 14-15, 2015 28 HTS Price Comparison Steve Gourlay’s paid price: Chinese companies’ quoted price: SSTC: YMCO RMB 20,000/kg (USD 3,300/kg) InnoST: Bi-2223: RMB 15,000/kg (USD 2,400/kg) Goal for HTS cost reduction (discussed with vendors): Jc x 10 and cost x 0.1 in 20 years

29. W. Chou Beijing-Chicago Workshop, Sept 14-15, 2015 29 Collaboration on Specific R&D SC magnet:  LBNL: Steve Gourlay, Gianluca Sabbi  BNL: Ramesh Gupta, Peter Wanderer, John Skaritka, Bob Palmer SRF:  INFN-Milan: Carlo Pagani  BNL: Sergey Belomestnykh (to move to Fermilab)

30. 30 DOE – IHEP Workshop on Physics (Aug 2015, Beijing) A summary report by Charles Young (LBNL) and Xinchou Lou (IHEP) will be published soon.

31. W. Chou Beijing-Chicago Workshop, Sept 14-15, 2015 31 Future Joint Workshops in Planning 2 nd IAS Workshop on CEPC (Jan 2016, Hong Kong) ICFA mini-workshop on SRF HOM damping Joint workshop with CERN on dynamic aperture Joint workshop with the new ICFA panel on sustainable accelerators/colliders on “Green” colliders (power consumption minimization)

32. 32 e+e- R&D #1 – Power Consumption W. ChouBeijing-Chicago Workshop, Sept 14-15, 2015 Half of a nuclear power plant Assuming 6 months operation per year, electricity cost ~RMB 1B (USD 150M) a year Goal: to reduce it by 40% to ~300 MW

33. Relative Power Consumption 9% 16% 5% 10% 6% 48% 2% 3% 33

34. 34 Power Consumption Reduction Increase klystron efficiency (from 50% to 80-90%, e.g., the new klystron called collector potential depression or CPD under development in Japan) Improve magnet design (smaller aperture, copper conductor) Reuse of heat in the cooling water for civil purpose This is a common issue for many future accelerators. ICFA is considering to form a new panel to work on it

35. 35 Summary The Pre-CDR was basically a national effort with limited international collaborations. But when the project enters the R&D phase (and later the construction phase) with significant funds from the government, the collaboration must become more formal and be greatly strengthened. The MOU between the IHEP and U. of Chicago is an important step in this direction. There are many collaboration models, some are very successful (e.g., CERN and the LHC), some in trouble (e.g., ITER), and some failed (e.g., SSC). The ILC, CLIC, FCC, LBNF/DUNE, FAIR, XFEL etc. are all relevant examples, which we will learn and discuss at this meeting as well as at the following IAC meeting. W. Chou Beijing-Chicago Workshop, Sept 14-15, 2015

36. Questions? 36 W. ChouBeijing-Chicago Workshop, Sept 14-15, 2015