SuperKEKB Status
Mika Masuzawa, Hiroyasu Ego, Makoto Tobiyama
KEK Accelerator Laboratory

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Recent operation2

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Especially on 2022b runs
 Strongly required to get higher “peak” luminosity for the 10years evaluation process of MEXT.
• Decided to skip various machine studies to understand machine.
• Could not repair damaged collimator heads.
• Needed to skip the regular maintenance.

 Due to crazily increasing electricity costs, we had no choice
but to discontinue operation and enter LS1.
• The rising of electricity costs is continuing‒ we are doing our best to reduce thestandby power after stopping the operation of 2022b.
• (Almost) stop the water pumps.
• Stop the air conditioning of the power supply buildings and the arc section of thetunnel.
• Tuning off the lights of the tunnel in the night.
• 25Hz operation of Linac.

4 Evaluation of large-scale research projects (report) "Exploring newlaws of physics through advanced B-factory accelerators“ Evaluation of large-scale research projects (report) "KEK Super B
Factory Project“• Only Japanese report available• https://www.mext.go.jp/b̲menu/shingi/gijyutu/gijyutu4/021/index.htm• This project aims to discover and elucidate new laws of physics beyond the standard

theory by further improving the performance of the SuperKEKB accelerator, which
has the world's highest collision performance as an electron-positron collider. , It canbe evaluated as a plan that has a strategic nature and can gain the consensus ofdomestic and overseas research communities and the support of society and thepublic.
• In order to achieve the three scientific goals based on the excellent results that havebeen achieved so far, and to obtain scientific results, Japan will continue to take thelead in improving the performance of accelerators and appropriately promoting
maintenance and management, including countermeasures against aging. It is
expected that they will lead cutting-edge particle physics research and maintain theirinternational competitiveness while fulfilling their important roles.
• Considering the above comprehensively, it is evaluated that this plan should beactively promoted and should be started as soon as possible.
5Electricity charges• Rapid increase of “Fuel surcharge” starting last year.
• Electric power co. (Kyushu Electric Power Co., inc.) strongly requested the change ofcontract to new scheme “Market-linked electricity rate”– KEK (Tsukuba campus) had nochoice but to accept the proposal.
• Resulting very high rate starting Dec.

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KEKBʼs efforts to save electricity
3.5 10 4

Cumulative power consumption

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2.5 10 4Plan(MWh)Results(MWh)2 104

Need to pay• 4/5 of Linacelectricity (duringPF/PF-AR operation)• 3/5 of facilities(Applied ResearchLab.)

1.5 10 4

1 10450000Apr/1May/1Jun/1 Jul/1 Aug/1Sep/1 Oct/1 Nov/1Dec/1

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Comparison with previous years
 FY2021 w/o operation• 4,066 MWh (September) FY2022• 1378 MWh (November)

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FY2023
 If the current electricity bill continues as it is, not only will webe unable to operate any accelerators at all next fiscal year,
but there is a risk that we will not be able to even maintain theequipment.
• In order to operate the SuperKEKB accelerators as planned (~5 months), large
amount of additional budget (of 10 B yen or more) might be required.

 We will need to check the accelerator components before
restarting operation (conditions, water cooling, stabilities, etc).

1011After LS1
 The prices of the items (magnets, concreate radiation shield,
lead radiation shield, etc.) have skyrocketed, and the delivery
times have been terribly delayed.
• We are making every possible efforts not to delay the startup of the acceleratorsin October next year, including the budget carryover procedures.

 Belle II will decide the starting-up time, around next May.
• Might be too late for the preparation of IR recovery works.
• PXD sensors situation.

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Human resources ACCL 3rd (Head: M. Tobiyama)• Safety, Vacuum, RF system, NC cavity, SC Cavity, Cryogenics, Acc. Theory• Prof.: 5, Assoc. Prof.: 8, Assist. Prof.: 4, Technical staff: 10, Re-hired: 9 ACCL 4th (Head: M. Masuzawa)• Control, BT, Beam Instruments, Magnet, SC Magnet, Commissioning• Prof.: 4 Assoc. Prof.:8 Assist. Prof.:6, Technical staff: 10, Re-hired: 11

 ACCL 5th (Head: H. Ego)
• Prof.: 6, Assoc. Prof.: 7, Assist. Prof.:5 PD 1, Technical Staff:6, Re-hired:1413

The 26th KEKB Accelerator Review
 23rd (8/Jul/2019-10/Jul/2019)• In person review

 24th (15/Jul/2020)• Online review

 25th (1/Sep/2021 ‒ 2/Sep/2021)• Online review

 International Task Force ARC review (7/Mar/2022)• Online This review (13/Dec/2022 to 14/Dec/2022)• In person + Hybrid review

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Summary Peak luminosity of 4.7x1034cm-2s-1 has been achieved.
 Demonstrated stable operation over 1A in the LER (withsmaller bunch current less than 0.7mA/bunch).
 We have successfully passed the MEXT review.
 We are doing our best to deal with the soaring electricity bills,
but at the moment the outlook for operating costs is not bright.

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Backup slides

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