SuperKEKB Construction Plan�

Kazunori AKAI�KEK��
7 Feb. 2011�
Accelerator Review Committee�Outline�
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Introduction�
Budget�Construction strategy�
Major items for construction�
Schedule�
Cost�
Human Resources�

SuperKEKB Construc0on Plan (K. AKAI)

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Milestones this year�•

22 Jun. 2010: A budget of 10 Billion Yen announced�
–The MEXT, the Japanese Ministry that supervises KEK, has announced that it will appropriate a budgetof 100 oku-yen (approx $110M) over the next three years starting this Japanese fiscal year (JFY2010)
for the high performance upgrade program of KEKB. This is part of the measures taken under the new"Very Advanced Research Support Program" of the Japanese government. (“KEKB upgrade plan has
been approved”, Press Release 23 Jun 2010; KEK web site)�

•30 Jun. 2010: KEKB operation was shut down, and KEKB upgrade
started.�

•

24 Dec. 2010: SuperKEKB approved in FY2011 budget �–

The Cabinet of Japan announced the national budget plan of JFY2011 last Friday, where SuperKEKB
upgrade was approved as requested by MEXT. This will be final decision of SuperKEKB after approval by
the Japanese Diet. (“Green light from the Cabinet”, M. Yamauchi to Belle II members)�

SuperKEKB Construc0on Plan (K. AKAI)

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Dismantle KEKB on going�•••

Dismantle LER arc section (bending magnets, wigglers, beam pipes, etc.) almost done. �Both rings at Tsukuba straight section will be dismantled in FY2011. �
HER arc section will be kept. �

Bellows taken out from LER
Ceremony for star0ng removal of magnets (M. Masuzawa)

Removing bending magnet

SuperKEKB Construc0on Plan (K. AKAI)

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Removing LER bending magnets (107 magnets all done)

Removing LER beam pipes from Q magnets

SuperKEKB Construc0on Plan (K. AKAI)

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Budget�•"Very Advanced Research Support Program”�
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Other budgets�
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MEXT has announced that it will appropriate 10 Billion Yen for three years (FY2010–12).�
Among this, 7.5 Billion Yen was already appropriated in FY2010.�
This budget is for upgrading LER vacuum system and LER magnet system.�
21.4 Billion Yen for SuperKEKB construction is expected for FY2011-14. �Among this, approval of 4.06 Billion Yen for FY2011 was announced by the Cabinet.�
They are for various accelerator components and facilities, including DR tunnel, buildings
for DR and MR and cooling system.�

Total budget�––Total construction budget is 31.4 Billion Yen. �The operation budget is expected in FY2014 and later. �

FY2010FY2011FY2012

Very Advanced Research SP (10 Billion Yen)FY2013

FY2014FY2015FY2016

MR and DR commissioning

Other budgets for construc@on (21.4 Billion Yen)
We are here

Opera@on budget (con@nues ‐ ‐ ‐ )SuperKEKB Construc0on Plan (K. AKAI)

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Commissioning plan�
•Machine commissioning start�
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Main Ring and Damping Ring commissioning will start in the second half of FY2014.�
Linac is in operation for PF and PF-AR during the construction period. Test operation for
the upgrade will be performed in parallel. Commissioning of Linac for SuperKEKB will startin the beginning of FY2014. �

Detector�
–––The detector people want that the machine operation starts without Belle II. So themachine commissioning will start with some dummy chambers with a luminosity monitor
at the IR (so called BEAST). �
Belle II will be installed later in FY2015. �
IR configuration before Belle II installation is under discussion (for example, “Do we needsolenoids or special skew-Q, special radiation shield in the place of Belle, etc. with an
extra cost?”). We have no concrete plan for this so far.�

SuperKEKB Construc0on Plan (K. AKAI)

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Construction Strategy̲1�
•Design fixed or not fixed�
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Machine design has not been completed, in particular for difficult parts such as IR optics
and QCS hardware, chromaticity correction scheme and beam collimation scheme.�
On the other hand, a large amount of budget has already been appropriated (7.5 Billion
Yen for FY2010 and 4.6 Billion Yen for FY2011). The budget must be executed
appropriately.�
We first use the budget for those components that the design is already fixed such as
magnets and beam pipes at the arc section and wiggler sections. Fabrication of thecomponents that the design is not fixed yet such as those for the IR, sextupole region
and collimation system are postponed to FY2012 or later. �The due dates to fix those designs are presented from the viewpoint of construction
schedule (shown later). �

Before or after T=0.�
––Considering budget profile and schedule, we make differences between the required
performance at T=0 and other requirements that can be postponed for years. Thosecomponents indispensable at T=0 must be completed with a higher priority (see, next
slide). �
Large scale works that are difficult to do after the commissioning should also becompleted by T=0. This includes rearrangement of ARES cavities and reinforcement ofcooling pipes in tunnel. �SuperKEKB Construc0on Plan (K. AKAI)

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Construction Strategy̲2�
•Emittance�
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βy*�
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We may start with detuned optics, and then gradually squeeze. �IR configuration at T=0 is under discussion (as mentioned).�

Beam current�
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The design emittance is targeted from the beginning (at T=0). �
Main Ring magnets, beam pipes, injection system, etc. should be completed by then. �
The injector and Damping Ring should satisfy the low emittance at T=0.�

Start with low beam current. At T=0 the maximum current is less than the design value(maybe 60˜70%). Increase to the design current will take about two years or more. �Extensive rearrangement of cavities and RF system will be done during the construction
period. Fabrication and installation of additional RF stations will be divided into twophases (before and after T=0) �
Some of infrastructure (cooling, transformers) may be postponed for one or two years. �Charge requirement for Linac and DR is set to match the beam current increase (Forexample, 1 nC at T=0, 2 nC at +1year, 4nC at +2 years). This is to make a clear target
for the RF e-gun and e+ source R&D, and for the Linac and DR construction schedule.�

Beam energy�–Υ(4S) at T=0. Additional components needed (if any) in Linac for Υ(6S) will be
postponed. But necessary change for Beam Transport will be done by T=0. �

SuperKEKB Construc0on Plan (K. AKAI)9KEKB to SuperKEKB�Colliding bunches

Belle IINew IRe- 2.6 A!

New superconducting final
focusing magnets near the IP

New beam pipes& bellows

e+ 3.6 A!

Reinforce RF systems forhigher beam currents
Improve beam monitorsand control system

Redesign the lattice to squeeze theemittance (replace short dipoles withlonger ones, increase wiggler cycles)

New positron
capture section

e+ Damping ring

Replace beam pipes to suppress electron cloud(TiN-coated beam pipe with antechambers)

Low emittance electron gun

To get x40 higher luminosity

SuperKEKB Construc0on Plan (K. AKAI)

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Major items for construction�
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A large number of magnets need to be rearranged, replaced, and added toreduce the horizontal emittance of both beams to one-fifth to one-tenthof their present values. �To cope with the electron cloud issues and heating problems, antechamber type beam pipes will be adopted with a combination of TiN
coatings, grooved shape surfaces, and clearing electrodes. �A new final focus magnet system is being designed to squeeze βy*. �
The RF system will be strengthened, and the accelerating cavities modified
and rearranged to cope with the increased beam currents. �The beam monitor and control system will also be improved. �
Upgrades to the injector linac and beam transport system, including a new,low-emittance RF electron gun, improvements to the positron source, andinstallation of a 1.1 GeV positron damping ring, are designed to improve
the rate and quality of injected beams to deliver the required beams withincreased injection efficiencies.�
Cooling system will be reinforced for the magnets and vacuum system.�
Tunnel and buildings, additional transformers.�
Dismantle KEKB and install base plates. R&D, design, fabricate, and installcomponents. Check and adjust them for system commissioning.�
In my talk, some of the items are brieﬂy introduced.
Details will be given in the following talks by our colleagues.
SuperKEKB Construc0on Plan (K. AKAI)

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Magnets for LER arc�Replace bending magnets (˜100) with new longer ones to reduce
horizontal emittance.�
A. Morita, Y. Ohnishi, et al
Tunability of the LER cell

L= 0.89 m → 4 m

εx (nm)•αpSuperKEKB Construc0on Plan (K. AKAI)

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LER wiggler section�
•New 56 single pole wigglers and 112 half pole wigglers will be added tothe existing normal ones to double the wiggler cycles.�
KEKB

SuperKEKB

existing normal wigglers

SuperKEKB Construc0on Plan (K. AKAI)

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HER wiggler section�
•H. Koiso
Wiggler magnets will be installed to reduce the HER horizontal
emittance. For 6 wiggler sections among 10, present LER wiggler
magnets will be reused. The rest 4 sections may be filled in future.�

beam

LER wigglers to be May be ﬁlled
converted to HER. in future.
RF sec0on

SuperKEKB Construc0on Plan (K. AKAI)

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Ante-chamber type beam pipe�Structure– SR from beam is guided to the ante‐chamber.
– NEG pumps in the ante‐chamber.
– TiN coa0ng inside.

Concept

Merits– Suppress electron clouds.
– Reduce beam impedance.
– Reduce SR power density at the wall.



NEG pumps

Material

Beam
SR– Copper at wiggler magnet sec0on.
– Aluminum alloy at arc sec0on (reduce cost and manufacture 0me).

Arc sec0on (aluminum)
Wiggler sec0on (copper)
Inside view(clearing electrode for
wiggler section)

SuperKEKB Construc0on Plan (K. AKAI)

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Vacuum system�
•Beam pipes at LER arc section will be replaced with new aluminum-alloyante-chamber pipes (˜2000m). �–•

Copper ante-chambers will be used at wiggler sections in LER and HER. �
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Since the HER energy is reduced from 8.0 to 7.0 GeV, SR power at normal arc section
for the design beam current will be about the same as present KEKB. �
This reduces construction cost and work largely.�
Some of the HER components will be replaced with more robust ones such as comb-typegate valves and comb-type bellows for higher beam currents in future. ��

Tsukuba straight section for both rings will be made new.�
–•With clearing electrodes for LER.�

Present copper beam pipes at HER arc section will be reused. �–•

Fabrication starts this year. We have called for vendors. �

Optics changes. Ante-chambers will be used, copper for most part.�

Collimation scheme is under discussion. R&D of movable masks isunderway. �
Details will be given by Y. Suetsugu.

SuperKEKB Construc0on Plan (K. AKAI)

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Superconducting final Q�
 Final SC quads will be located as close to the IP as possible.
 Independent magnets in the LER and HER.

CryostatAn@ solenoid‐R
QC2LP
PM

QC1LP
+corr. coil

QC1RE
+corr coil

IP

QC2LE
PM

QC1LE
+corr. coil

CryostatAn@ solenoid‐L

QC1RP+corr. coil

SuperKEKB Construc0on Plan (K. AKAI)

QC2RE
PM

QC2RP
+corr. coil

QC1RE

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IR components�
•Design�
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Construction�
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Optics design including the effect of leakage field of QCS and other error sources tomake sufficient dynamic aperture has not been finalized yet. �
Local chromaticity correction scheme has not been determined.�
Hardware design including QCS, beam pipes, monitors and supports are under way. �
Assembly procedure is under discussion.�
Evaluation of background issues are under way. This may require serious change for the
IR design.�
T=0 scenario is not determined yet. �Fabrication of magnets in the Tsukuba straight section including the IR and local
chromaticity correction is postponed to FY2012.�
Fabrication of other IR components such as beam pipes and pumps is also postponed to
FY2012. �
In order to be ready for the commissioning in the second half of FY2014, fabrication of
QCS should start in the second half of FY2011. �

The IR design needs to be fixed until the autumn this year. �
Details will be given by N. Ohuchi, K. Kanazawa and H. Nakayama.

SuperKEKB Construc0on Plan (K. AKAI)18

RF system�unit

KEKB (opera@on)

SuperKEKB (design)

Ring

LER

HER

LER

HER

HER (base line)

HER

Wiggler

Full

None

Full

None

6/10

Full

7.007

7.007

2.6

2.6

Beam Energy

GeV

3.5

8.0

4.000

Beam Current

A

1.8

1.4

3.6

1585

1585

2500

2500

2500

2500

Number of Bunches

twice

twice

7.007
2.6

Bunch Length

mm

6~7

6~7

6

5

5

5

Energy loss/turn

MV

1.5

3.5

1.87

2.07

2.43

2.67

3.49E‐4

4.55E‐4

4.55E‐4

4.54E‐4

6.73

5.38

6.32

6.94

40

40

40

1.09

1.09

1.09

6.47

7.41

8.03

12.4

14.7

15.8

Momentum compac0on
Radia0on Loss

MW

Loss factor, assumed

V/pC

30

Parasi0c Loss

MW

1.56

Total Beam Power

MW

~ 3.5

~ 5.0

8.30

RF Voltage

MV

8.0

15.0

9.4

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•

2.7

4.9

three 0mes

Add HP&LL RF system and rearrange ARES cavities.�
Change ARES input couplers to larger coupling ones. �
Improve HOM dampers (ARES, SCC). �
SuperKEKB Construc0on Plan (K. AKAI)

Change to 1 Kly: 1ARES system(currently 1 Kly: 2 ARES)
Details will be given by T. Kageyama
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OHO

D4
1

RF
system�
KEKB

2

C

B

2

2

A

A

B

FUJI

D7

D5
E

E

C

D

C

B

1

Type “B” power supply (for one klystron)
Klystron, HP&LLRF system

D10

A

1

2

2

A

Type “A” power supply (for two klystrons)

D8

2

2

1

2

B

C

D

2

E

NIKKO

2

D C B A

D11

2

Lower
power
1

2

A B C

D

E

F

HER
ARES cavi0es

LER

SC cavi0es
Crab cavi0es

ARES cavi0es

Before T=0
Aler T=022

add 5 klystrons, HP&LL
add 3 power supplies
add 2 more klystrons, HP&LL,
add 1 more power supply

D4SuperKEKB (max. RF)
Aler T=0

D7

D5

2

2

H G F E D C B A

2
A B C

2

2

2
D E

F

F

add 2 klystrons, HP&LL
add 2 power supplies

2
E

D

2

C

B

2

A

A

B

add 2 ARES or SC

Aler T=0 add 2 klystrons, HP&LL

D10

D8
C

2

2

2

D

E

F

2

D C B A

2

D11

A B C

2

2
D

E

F

ARES or SC

add 2 ARES
convert to LER

removeremoveSuperKEKB Construc0on Plan (K. AKAI)

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Beam monitors�
•Beam position monitors�
–––Medium band detectors�
Turn by turn detectors�
New narrow band detectors (1GHz→509MHz)�
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Mass fabrication is scheduled in FY2011 and 2012.�

Displacement detection system�

Bunch by bunch feedback system�
––•R&D of these detectors are going on. �
Requirements from optics design should be fixed. �
Number of minimum detectors needed at T=0 should be determined. �

Button electrodes �•–

Details will be given by H. Fukuma

Transverse�
Longitudinal feedback system is also required in LER.�

Profile monitors�
––Visible light monitor�
X-ray beam size monitor�

–Beamstrahlung monitor�

Gated measurement�
Loss monitors, etc.�
SuperKEKB Construc0on Plan (K. AKAI)

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New positron damping ring�
We construct a positron damping ringfor the very low emiQance beam injec@on

Details will be given by M. Kikuchi

Beam energy (GeV)

1.1

Circumference (m)135# of train

2# of bunches/train

2

Maximum stored current (mA)

70.8

Horizontal damping 0me (ms)11

Injected‐beam emioance (µm)

1.7

Emioance @ extrac0on (H/V) (nm)42.5 / 2.07

Cavity voltage (Vc) (MV)

0.5

1.0

1.4

Bunch length (mm)

11.1

7.7

6.5

Momentum compac0on (α)

0.0141

Energy spread (%)

0.055

Electron cloud will be mitigated by TiN coated ante-chambers and solenoid windings.
Fabrication of magnets started in FY2010.
SuperKEKB Construc0on Plan (K. AKAI)

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Facility and Infrastructure�
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Main Ring�
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Add buildings for power supplies and cooling system�
Reinforce cooling system�
Reinforce transformers�Repair floor�
Stock area and working space�Damping Ring�––––

New tunnel�New buildings for power supplies and cooling system�
Cooling system�
Electricity�

Injector upgrade will be presented by T. Higo.

SuperKEKB Construc0on Plan (K. AKAI)

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SuperKEKB Ring construction schedule (1)�SuperKEKB Construc0on Plan (K. AKAI)24

SuperKEKB Ring construction schedule (2)�SuperKEKB Construc0on Plan (K. AKAI)

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SuperKEKB Ring construction schedule (3)�SuperKEKB Construc0on Plan (K. AKAI)

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SuperKEKB Ring construction schedule (4)�SuperKEKB Construc0on Plan (K. AKAI)

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SuperKEKB Ring construction schedule (5)�SuperKEKB Construc0on Plan (K. AKAI)28

Cost estimation�

1 (Billion Yen) = 12.3 M USD = 8.8 M EUR (as of 6 Nov., 2010)

Components

Cost(Billion Yen)

Remarks

Vacuum System

7 ‐ 8 beam pipes (ante‐chambers, electrodes, etc), pumps andother vacuum components

Magnet System

5 ‐ 6 magnets, power supplies, cables

IR upgrade

1 ‐ 2 QCS and other IR hardware

RF System

2 ‐ 3 reinforce RF sta0ons, rearrange and improve cavi0es

Beam monitor and control

2 ‐ 3 BPM, proﬁle monitors, feedback, control system, safetysystem, improve beam transport, etc.

Damping Ring

2 ‐ 3 Damping Ring components (magnets, vacuum, RF, monitors,
control, etc.)

Reinforce cooling system

4 ‐ 5 Change cooling pipes in tunnel, add cooling tower andpumps.

Tunnel and buildings

2 ‐ 3 DR tunnel, buildings for Linac upgrade, DR and MR

 Cost for the Injector and Belle upgrade is not included in the list.
 Discussion is going on to op0mize the plan between the Ring, Injector and Belle II.

SuperKEKB Construc0on Plan (K. AKAI)

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Human Resources�
Date

StatusNeededFTE (A)

Available FTE (B)Comments on (B)FTE short(A) ‐ (B)

Apr. 2011

under construc0on

77.1

60.1

Re0rement in Mar. 2011 and new persons
expected in April are taken into account.

17.0

Apr. 2013

under construc0on

77.1

55.1
+ new members (x)5 persons will be re0red

22.0 ‐xApr. 2015

0.5 year alercommissioning

70.0

47.1
+ new members (y)8 more persons will be re0red

22.9 –(x+y)•

About this table––•

Needed FTE is for the number of staﬀ members.
The HR for the Linac is not included in the list.

How to ﬁll the short FTE?
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Since some new persons are expected to join KEKB in April, the situa0on looks a liole beoer
compared with the es0ma0on last year.
S0ll about 20 people are short for construc0on.
Collabora0on with other project members and other laboratories.
– Field measurement of DR magnets by PF ring group.
– LLRF development with control group and cERL groupMore new members, more help by re0red persons, more collabora0ons are welcome.
SuperKEKB Construc0on Plan (K. AKAI)30

Summary�
••••SuperKEKB construction has started. Dismantle KEKB is going on. Massfabrication of magnets, beam pipes, etc. has started. �
Commissioning will start in the second half of FY2014. �
Discussion and optimization between machine design and construction isgoing on extensively. �Required performance and priorities, budget and cost, schedule andhuman resources are presented. �

SuperKEKB Construc0on Plan (K. AKAI)

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