1. SPPC General Status 唐靖宇 第二次 CEPC-SPPC 合作研究全体会议 2015 年 09 月 11-12 日, 高能所

2. Main topics General information Collider accelerator physics Technical issues Injector chain R&D planning About team and collaboration Summary 2

3. General information Since the last CEPC-SPPC study group meeting (May 16- 18) – Work on collider accelerator physics continues – Work on technical issues expanded – Schemes on injector chain updated – A paper on SPPC published on arXiv A NSFC fund for SPPC study approved (joint IHEP-USTC application) New fund from MOST for CEPC-SPPC R&D hopeful; 13th five-year planning CEPC-SPPC R&D also in course International collaboration strengthened, especially with BNL Study team gradually formed up Monthly group meeting maintained 3

4. Collider Accelerator Physics General parameters: all AP members (Tang Jingyu coordinates). BNL experts made important contribution (especially luminosity leveling) Lattice design: two persons (Su Feng, Chen Yukai) working on SPPC lattice, hopeful to get the first version by end year Collimation study: two persons (Zou Ye, Yang Jianquan) working on the study. Good progress has been made. A discussion meeting (joint CEPC and SPPC) held on Sep. 10 Instabilities: Liu Yudong continues to work electron cloud effects, Xu Wei joined to look at all instabilities Beam-beam effects: Guo Yuanyuan takes the main task, as Xiao Ming continues to make contribution. Injection and extraction: TsingHua (Li Guanrui, Zheng Shuxin) 4

5. Longitudinal dynamics: Peng Yuemei continues to work on it, with some help from Dai Jianping (especially on RF systems and injector accelerators) e-p collision: Peng Yuemei continues to put one eye on it Other topics: needing more volunteers to work on 5

6. Technical issues High-field superconducting magnets – ICFA mini-workshop on HFM held in Shanghai in June – Some funds for R&D efforts (Xu Qingjin, and also from CSNS muon source Hou Zhilong from NSFC) – Group expanded (especially with participation of USTC members) Beam screen and vacuum – Zhu Kun (and a PKU student) studying new schemes (with inspiration of FCC new ideas) – Wang Yong (and a student) studying all vacuum issues at SPPC Beam instrumentation and controls – Some progresses? (Sun Baogeng, Yang Yongliang, Leng Yongbin, Yan Yingbing) 6

7. Machine protection – Xu Hongliang did surveys and begins to look at the SPPC case, to coordinate information from other systems RF systems – Dai Jianping looking at all RF systems (collider and injector rings) Cryogenics – To be started, (Li Shaopeng) 7

8. Injector chain Updating the schemes for the accelerators to maximize the potential of each stage for parallel physics programs. p-Linac/i-Linac: Lu Yuanrong started to make survey and first design MSS: Hong Yang working on lattice design 8

9. R&D planning We need long-term R&D efforts to meet the requirements for building SPPC; some of key technologies are extremely challenging. Both funds and manpower are needed CEPC-SPPC management is making efforts to obtain R&D funds from MOST and NDRC; SPPC is a part of the package. We must provide solid materials (needs, schemes and roadmaps, planning and collaboration) to support the applications  today’s discussion 9

10. About team and collaboration SPPC study team is gradually building up, with more young people joined recently, mainly from IHEP and USTC, but the deficit is still significant, even in this stage. Subgroups will be gradually formed to work more efficiently. Collaboration between IHEP and USTC is strengthened via the NSFC fund. Hope the MOST fund will help the strengthening of the collaboration among all member institutions Collaboration with BNL has good output, hopeful to be continued Collaboration with oversea Chinese physicists continues Collaboration with international HFM experts continues Main problem: it is not easy to establish collaboration with FCC 10

11. Summary We have been making progress on SPPC study steadily. Study team gradually building up, but more people are welcomed. Along with funds to come, both design studies and R&D efforts will be organized more efficiently. Strong collaboration within domestic institutions and with international labs or experts will be strengthened. We should work together for the CDR report by end 2016. 11

12. WELCOME COMMENTS! 12