Belle II/Superkekb Perspective from KEK

Belle II/SuperKEKB perspective from KEK

Katsuo Tokushuku

Institute of Particle Nuclear Studies (IPNS), KEK

US Belle II Operations Review (29/Oct/2020) 29/10/2020 1 Belle II New superconducting /permanent final focusing quads near the IP SuperKEKB and Belle II New IR Nanobeam colliding bunches e+ 4GeV 3.6 A e- 7GeV 2.6 A SuperKEKB Target: L = 8x1035/cm2/s

Replace short dipoles with longer ones (LER) Add / modify RF systems for higher beam current

Positron source New positron target / capture section Redesign the lattices of HER & LER Damping ring to squeeze the emittance @1.1 GeV TiN-coated beam pipe with antechambers To inject low emittance positrons Cu for wigglers and Al alloy for the rest

Low emittance gun To inject low emittance electrons

29/10/2020 2 Belle II New superconducting /permanent final(design) focusing quads near the IP SuperKEKB and Belle II New IR Nanobeam colliding bunches e+ 4GeV 3.6 A Nano beam scheme: - SuperKEKB e 7GeV 2.6 A Modest (x2) current increase. Target: L = 8x1035/cm2Ambitious/s challenge to reduce the beam size (x 1/20)

Replace short dipoles with longer ones (LER) Add / modify RF systems for higher beam current

Low emittance gun To inject low emittance electrons

29/10/2020 3 SuperKEKB Luminosity in 2020a,b • Max current = 770mA(LER) / 660mA(HER) 34 -2 -1 • Lpeak = 2.4 x 10 cm s (world highest) “Crab Waist” scheme • Int. luminosity/day = 1.346 fb-1/1.498 fb-1 recorded delivered KEKB record 34 -2 -1 • Lpeak = 2.11 x 10 cm s rec. -1 • Lday = 1.48 fb (2009.6.14) * * • LER: βx /βy = 80mm/1mm → 60mm/0.8mm * * • HER: βx /βy = 60mm/1mm → 60mm/0.8mm

Operation history in 2020a,b Specific luminosity

IHER[mA]

ILER[mA]

Lpeak [x1034 cm-2s-1] -1 recorded Lday[fb ] /delivered

-1 Lint[fb ] 4 SuperKEKB machine parameters in 2020b

c.f. KEKB

1190 / 1640

2x1034

Higher Luminosity with the lower beam current: Success of the nano-beam scheme 5 Belle II under COVID-19

▪ SuperKEKB/Belle II was operated under Covid-19 pandemic while minimizing risk of infection: Closed space • Minimize person-to-person contact and avoid 3C Crowded places − Remote control room shifts and expert shifts Close-contact settings − Online communications in run operation (chat tools), run meetings etc. − Hygiene (face mask, alcohol disinfection, ventilation, …) ~40 Belle II colleagues on-site KEK campus outside KEK Beam background HV ctrl (SpeakApp) (RocketChat) Belle II Exp Hall Sub-system experts

Accelerator ctrl room Another bldg Ctrl room Safety shift Remote ctrl room shift

VPN

“New normal” scheme for sustainable operation under discussion. 6 Safety at KEK Slides for safety training issued in March 2016.

All who work in the experimental hall are required to read.

24 pages

DOE/PNNL contributed to the safety document of KEK 7 Belle II Luminosity

74 fb–1 1.3 fb–1/day

Run time fraction of SuperKEKB operation in 2020

Scheduled 10 fb–1 maintenance 6 fb–1 Belle II trouble Accelerator trouble

Accelerator Physics tuning run 56.7% ICHEP2020 dataset 34.6(3.2) fb–1 on-(off-)resonance 8 Review Reports B-factory Program Advisory Committee (BPAC) review report (June 2020)

Accerelator Review Committee (ARC)review report (July 2020)

9 Near Term Prospects

~1ab-1 FY2020 runtime Long shutdown 6.5 mo. /5.4 mo. ~Belle Lint resume operation 240 fb-1/140 fb-1 Replacement on October 19 • full-layer PXD 110 fb-1 74 fb-1 • part of TOP MCP- PMT 04 07 10 21/ 01 04 07 10 2020 a+b 2020 c 2021 a+b 2021 c

2020c run: Beam Injection started on 19/Oct as planned.

10 KEK High Energy Accelerator Budget plan for FY2020 and 2021 Research Organization • We got a few percent increase in the project budget for FY2020, which will enable us to operate beams for at least 5.4 months. We are still negotiating for an extra allocation from the KEK internal budget to add ~1 month of operation. The final result will be known in early November. (We think the success probability is high as no big typhoon /earthquake /tornado hit KEK this summer.)

• The process for the FY2021 budget request is on-going with ~one month delay from the usual deadline this year. • It is difficult to increase the budget during the COVID-19 problem but at moment the MEXT is negotiating with the MOF for a (slight) increase from FY2020. • The MEXT has asked to align the 2021 budget request to the plan submitted for the MEXT roadmap (see next page). • 5.7 months of operation in FY2021. (shorter than our goal (8months), taking account of the start of the long shutdown for the PXD replacement.) • Modest budget requests for upgrade/maintenance

MEXT: Ministry of Education, Culture, Sports, Science and Technology MOF: Ministry of Finance 11 29/10/2020 KEK High Energy Accelerator Long Term Plan Research Organization • KEK submitted the 10-year SuperKEKB project to the Master plan 2020 of the Science Council of Japan (SCJ). The project has been ranked as one of the 31 most important projects. • Following the SCJ master plan, the MEXT updated their roadmap 2020. Very recently the results have been shown. The SuperKEKB/Belle II project was selected as one of 15 highest priority projects with an “AA” grade (the highest possible). • We proposed a new (non-detailed) budget profile and a new running plan. • The important point of this revision is to let the MEXT know that this is not a simple 10 year operation but we will also invest in an innovative upgrade to reach our goal (50 ab-1) with a better scheme. • The detailed plan is under investigation. The actual plan will be finalized seeing the progress of the current luminosity improvement. The current direction is to reduce the beam size further rather than increasing the beam current. An example is shown on the next side. Details will be defined later and assessed by the external review committees (i.e. BPAC and Accelerator Review Committee (ARC)).

29/10/2020 12 KEK High Energy Accelerator SuperKEKB/Belle II Long-term Luminosity Profile Research Organization

Update plan based on the past results for the near future. The long term plan is to be assessed by the review committees.

35 -2 -1 Lpeak > 6 x 10 cm s after modification of SuperKEKB (partial RF, IR, …) and Belle II Reach 50ab-1 goal around 2030

1.0 0.6 0.5 0.3 (mm)∗ 𝛽𝛽𝑦𝑦 13 29/10/2020 The Geography of the International Belle II collaboration Oct. 2019 Iowa State University U.S.A. Nanjing Normal University China Feb.2020 Chulalongkorn University Thailand June 2020 Zhengzhou University China

Belle II now has grown to ~1000 researchers from 26 countries

This is rather unique in Japan. The only comparable example is the T2K experiment at JPARC, which is also an international collaboration Youth and potential: There are ~330 graduate students in the collaboration 29/10/2020 14 US Belle II, 18 institutes, 120 members

Brookhaven National Laboratory (BNL) University of Cincinnati Carnegie Mellon University University of Florida Duke University University of Hawai’i Iowa State University University of Louisville Indiana University University of Mississippi Kennesaw State University University of Pittsburgh Luther College University of South Alabama Pacific Northwest National Laboratory (PNNL) University of South Carolina 29/10/2020 15 Virginia Tech Wayne State University Structure of Belle II Resource Review

KEK Belle II Collaboration

KEK

Director of Director of ACCL-KEK IPNS-KEK Financial Board

KEK B-factory Computing Steering Group Finance (CSG) Accelerato Program Oversight r Review Advisory Panel Committee Committee Chair: F. Chair: T. (FOP) Representa- Zimmerman Nakada tives of FA’s n (CERN) (Lausanne) Next FOP full-remote meeting will be held on 13/Nov/2019., starting at 21:00 in JST, (i.e. in more US-friendly time!).  Computing Lists of Committees’ members are in backup Resource slides. Scrutiny Committee of FOP 29/10/2020  M&O cost 16 KEK High Energy Accelerator Summary Research Organization

 The Phase III physics run with Belle II vertex detectors started in March 2019. Many significant improvements have been made in SuperKEKB operation. The world record for instantaneous luminosity was updated in June 2020.  The ten year plan for the SuperKEKB/Belle II project has been ranked high in the MEXT roadmap. A detailed plan for implementation of the accelerator improvements is being made and will be reviewed in the BPAC and ARC.  International support is essential for the project. We are continuing to improve the communication with the collaboration and the funding agencies.

29/10/2020 17 KEK High Energy Accelerator More information Research Organization

29/10/2020 18 KEK High Energy Accelerator Research Organization Belle II Detector

BEAST (Background KL and muon detector: commissioning detector) Resistive Plate Chambers (barrel outer layers) Scintillator + WLSF + SiPMs (end-caps , inner 2 barrel layers)

EM Calorimeter: CsI(Tl), waveform sampling (barrel+endcap)

Particle Identification electrons (7 GeV) TOP detector system (barrel) Prox. focusing Aerogel RICH (fwd)

Beryllium beam pipe 2cm diameter

Vertex Detector 2 layers DEPFET + 4 layers DSSD positrons (4 GeV) Central Drift Chamber He(50%):C2H6(50%), small cells, long lever arm, fast electronics US contributions in red 29/10/2020 19 Approval Procedure of CRL and M&O

Belle II Collaboration proposes revised M&O and CRL to FOP for approval. 10/Sep/2020 M&O Cost Allocation SCFOP SCFOP reviews M&O Financial Board drafts

FB and makes M&O cost allocation. B2 recommendation. Collab. Computer Resource Level (CRL) 10/Feb/2020

Computer Steering BPAC BPAC reviews CRL Group of Belle II and makes

Collaboration (CSG) CSG drafts CRL. recommendation. 13/Nov/2020 FOP reviews and approves CRL and M&O. FOP Receive the approved CRL and M&O allocation. Director Inform FA’s about the result. of IPNS 29/10/2020 20 KEK High Energy Accelerator Members of the Scrutiny group Research Organization

Karsten Buesser DESY (Chair) Didier Contardo Lyon Fabio Cossutti Trieste Kazunori Hanagaki KEK Torre Wenaus BNL Un-Ki Yang SNU

(red: new members)

29/10/2020 21 KEK High Energy Accelerator BPAC members Research Organization  Current members (since April 2018) Tatsuya NAKADA （EPFL, Lausanne) Chair Gloria CORTI (CERN) Marcel DEMARTEAU (ANL) Roger FORTY (CERN) Belen GAVELA (UAM,Madrid) Stefania GORI (Cincinnati) Masaya ISHINO (ICEPP, Tokyo) Vera LUTH (SLAC) Niko NEUFELD (CERN) Michael SULLIVAN (SLAC) Hiroyasu TAJIMA (Nagoya) (red: new member since April 2020)  Computing Resource Review : Tatsuya NAKADA （EPFL, Lausanne) Chair Gianpaolo CARLINO (Naples) Wouter HULSBERGEN (Nikhef) Pere MATO (CERN) Patricia Mcbride (FNAL) 29/10/2020 22 MEXT Roadmap 2020 What was SCJ Masterplan 2020? SCJ Master Plan 2020 selected 31 priority projects out of 150, ranging all fields of sciences subsuming humanities, social sciences, life sciences, natural sciences, and engineering [Category I: new projects and continued (revised) projects from MP2017 ]. There are also 15 ongoing projects, which has selected in one of the past MPs [Category II]. SuperKEKB has been in category II for two periods, after which we are asked to submit again as a new project in Category I.

150 applications in Cat-I (2019.2-3)

146 evaluated (2019.4-6) SK-Gd, ILC, HK 59 new proposals are called for hearing (2019.9) 15 Cat-II projects J-PARC 16 new proposals selected as priority projects 15 continued (revised) projects Belle II KAGRA LiteBIRD 31 priority projects (2020.1) HL-LHC

31 priority projects and 43 semi-final projects in Cat-I (total 74) are the candidates of MEXT RM. MEXT RM 2020

74 applications (2020.2)

17 (15(/31)+2(/43)) invited to hearing (2020.8) 15 (13+2) listed in the J-PARC RM (2020.9) Belle II SK-Gd KAGRA LiteBIRD What MEXT RM does (as described in the report)

• RM enables a strategic and planned policy decision based on thorough scientific evaluations. • Enables to promote large scale projects while gaining supports from society and citizens. • Enables to handle international competitions and cooperation promptly and adequately. • Urge communities of researchers to consider what are the future goals and what are required to achieve the goals subjectively and with a broad perspective. • Prompt interactions between different communities and transversal studies on complicated scientific challenges. • Opinions from communities can be sorted in the form of the RM in advance. What MEXT RM brings

• Merits in a bottom-up style project can be incorporated to a top-down decided project in one way or another. • When a new supporting scheme to large projects comes up, for example, as a supplemental budget, researchers communities can quickly and effectively utilize the new scheme. • Governmental agencies other than the MEXT concerning research and development can also easily understand the trend and concrete needs in each field. • For an academic field where the research is carried out in a large scale and the international cooperation is essential, the RM shows how the large scale projects should be promoted, and therefore it can prompt international cooperation. Evaluation

A: basic viewpoint 1. Academic significance 2. Agreement in the researcher’s community 3. Main body to execute the project 4. Shared use, collaboration 5. Validity of the project

B: priority viewpoint 6. Urgency 7. Strategy 8. Support from society and citizens

Rating is given for each item Ranking (a/b/c) is done based on the rating 15 projects on RM are carefully chosen from high rank project SuperKEKB

Straight A’s KEK High Energy Accelerator Safety at KEK Research Organization

DOE/PNNL contributed to the safety document of KEK (as already reported in 2014)

22 pages

29/10/2020 30 KEK High Energy Accelerator Safety at KEK Research Organization Slides for safety training issued in March 2016.

All who work in the experimental hall are asked to read.

24 pages

29/10/2020 31 KEK More Improvement? High Energy Accelerator Research Organization

 The users meeting were held in Oct/2018 and June/2019 Organized by KEK Users Office, with attendance of KEK executive directors and IPNS directors. Many requests/advices from Belle II collaboration. The Q&A summary is on the web page https://www2.kek.jp/uskek/eng/UG-meeting.html No meeting planed in this year because of COVID-19.

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