Overview of Construction Status�
Two topics are included in this talk:� Recovery of KEKB rings from the earthquake� Construction status�

K. Akai (KEK)�
Feb. 20, 2012�
17th KEKB Accelerator Review Committee�

Recovery of KEKB Rings fromthe Earthquake�Overview of construction status�

K. Akai (KEK)�

2�

D5 power supply building�Wall panel fell down�

Cables out of rack�Panels and floor in
the control room�

Overview of construction status�

K. Akai (KEK)�

3�

LLRF in D5�

20cm	
  fell	  down	 More than 10 LLRF control racks for 2 RF
stations fell down with floor by 20cm. Cables
under the floor also damaged. � Other 10 racks fell down by 1cm.�

Overview of construction status� More than 30 racks have been removed.
Most of the cables, some of which are directly
connected to tunnel, were also removed. � Repair floors underway.� New LLRF system to be installed.�

K. Akai (KEK)�

4�

Air-fin cooler on the roof for klystrons� Stands of air-fin coolers and baseplates on the roof are damaged. � Damaged in D1, D2, D4 and D5. �

Overview of construction status�

AFC on D4 roof�

K. Akai (KEK)�

5�

Klystrons� Stoppers of klystron sockets are damaged(half of all 35 klystrons).�
 Klystron positions moved (almost all). �
Stoppers damaged�

M. Yoshida�Position moved�

Stoppers deformed�

Anchor bolts at cooling tower released�	
  Pumping	
  system	
  successfully	
  restarted,	
  and	
  vacuum	  in	
  klystrons	
  was	
  healthy.	
  	
  
	
  Stoppers	
  are	  being	  reinforced.	
  	
  High	  power	  test	  to	
  be	
  conducted.	
Overview of construction status�

K. Akai (KEK)�

6�

Wiggler magnets in stock building� Magnets that were stocked in a building moved and collided each other.� Coils of some magnets seemed deformed. �

Overview of construction status�

K. Akai (KEK)�

7�

Wiggler magnets check after 3.11�
 Field measurement of all (˜150) wiggler magnets was performed.� Fortunately, all magnets are found healthy. �Overview of construction status�

K. Akai (KEK)�

8�

Beam pipe bellows� 21 bellows in D1 were opened, and checked inside. � One of them had damage on three RF contact fingers.�
 It is suspected that it shrank due to the earthquake. � 3 bellows in D11 were opened and checked inside. � One of them had damage on three RF contact fingers.�
 It is suspected that it shrank after expanded to almost its limit.�

Overview of construction status�

K. Akai (KEK)�

9�

X-ray check of all bellows planned� Damage inside bellows can be checked using X-ray
without opening to the air. � All HER bellows will be checked this year. �

Y. Suetsugu�

撮影条件 	
  IPサイズ：3・1/3×12インチ 	
  X線：110kV、5mA	  	
  距離：700㎜	
  	
  露出：5sec	Overview of construction status�

K. Akai (KEK)�

10�

Bellows X-ray check�Overview of construction status�

K. Akai (KEK)�

11�

Tunnel floor, wall, ceiling�Big	
  gap	  (several	  mm)	
  generated	
  at	
  expansion	
  joints.	
  Alignment	
  of	
  magnets	
  shiNed	  accordingly.	

↑ Floor crack at D11 expansion joint�↓ Floor crack at Fuji expansion joint�Overview of construction status�

↑ Water leak at D10 expansion joint ceiling�↓ Floor crack at the same expansion joint�

K. Akai (KEK)�

12�

Difference between before and after the earthquake�
Magnet group�

Moved in the whole ring. In particular, as much as
4mm at the expansion joints between straight and arc
sections. Re-alignment of whole ring is necessary.�

Overview of construction status�

K. Akai (KEK)�

13�

Summary of the earthquake issues�
• Damages�
– Serious damage on various components in power supply buildings, including
klystron stands, air-fin cooling towers, LLRF, and monitor control system. �– Damages on components in the tunnel seemed lighter than those in thebuildings.�
– HER bellows had some troubles. Need investigation. �– The expansion joints in the tunnel moved, and magnets alignment changed.�
– Other components such as radiation shields, cooling pipes, some magnets. �• Recovery�– Urgent cures (vacuum leak check, field measurement, system check etc.) weredone immediately.�
– Fortunately, all wiggler magnets in stock buildings found healthy, according tofield measurement.�
– Large scale recovery work started after the supplementary budget for
restoration and rehabilitation became available in January 2012.�
– Investigation of damages still continues, including X-ray survey of bellows,
high-power test of klystrons, etc. �

Overview of construction status�

K. Akai (KEK)�

14�

Construction Status�

Overview of construction status�

K. Akai (KEK)�

15�

SuperKEKB	
  construc/on	
  schedule	
FY2010	

FY2011	

KEKB	
  stop,	  ConstrucRon	
  start	 Dismantle	
  KEKB	FY2012	

Revised	  on	
  Feb.	
  10,	  2012	

FY2013	

FY2014	
T=0�
in FY2014�
(early 2015)�

We are here�

FabricaRon	
Baking,	
  TiN	
  coaRng	

Beam	
  pipes	
  and	  vacuum	  components	

Install,	
  system	
  check	
FabricaRon	

Magnets	
  and	
  power	
  supplies	RF	
  system	

SuperKEKB	  commissioning	

Field	
  measurement	
Install,	
  alignment,	
  system	
  check	
Reinforce	
  and	
  rearrange	
System	  check	

R&D	

Monitor	
  &	
  control,	  Beam	
  transport	  	  	

FabricaRon	
Install,	
  system	
  check	

OpRcs	
  and	
  hardware	
  design,	
  R&D	
FabricaRon	

QCS	
  and	  IR	
  hardware	MR	
  infrastructure	Damping	
  Ring	MR	  buildings	
  construcRon	

Install,	
  system	
  check	

Cooling	  system	  reinforcement	

Components	
  FabricaRon	
DR	
  tunnel	  construcRon	e+e-­‐	
  Injector	
Overview of construction status�

Upgrade	
  and	
  operaRon	
  for	
  PF/PF-­‐AR	
K. Akai (KEK)�

Install,	
  alignment,	
  system	
  check	DR	
  buildings	
  construcRon	
Injector	
  low	
  emi^ance	
16�Commissioning plan�• Phase 1: commissioning with Beast II�– Start early 2015 in FY2014, and continues for about half an year.�
– Hardware and optics tuning, vacuum scrubbing, BG study, and collision tuning
will be performed. �– Target luminosity in this phase is 1x1034 cm-2s-1.�
– Belle II solenoid is required to be implemented by then for the low beta beamtuning. �• Phase 2: commissioning with Belle II�– Start at the end of 2015.�
– Machine tuning continues to increase luminosity with Belle II data taking.�

• This plan is agreed between SuperKEKB accelerator
and Belle II. �

Overview of construction status�

K. Akai (KEK)�

17�

Prioritizing for T=0�
• Emittance�– The design emittance is targeted from the beginning (T=0). Main Ring magnets,
beam pipes, injection system, etc. should be completed by then. The Injector andDR should satisfy the low emittance at T=0.�

• βy*�

– Although we may start with detuned optics, βy* should be squeezed in thecommissioning phase in about half year. Necessary hardware to achieve design βy*must be implemented by T=0. �• Beam current�– Considering budget profile and schedule, about half the design beam current istargeted in the first commissioning phase. �– Some components as well as infrastructure needed for the design beam current
may be postponed after T=0. However, works that are difficult to do after thecommissioning, such as rearrangement of cavities, reinforce cooling pipes in tunnel,
will be completed by T=0. �• Bunch charge at Injector�
– Charge requirement for Linac and DR is set to match the beam current increase(roughly, 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 the Linac and DR construction
schedule.�

Overview of construction status�

K. Akai (KEK)�

18�

Beam Energy�• Design �– Original design maximum energy is 11.05GeV at Υ(6S). �• Recent request for higher energy�
– Requirement to investigate feasibility and issues for higher energy more than
11.5 GeV to around 12GeV was given by Belle II last autumn. The high energy
running, if any, will be after several years running at Υ(4S) ˜ Υ(6S).�

• Investigation�
– We investigated limitations from various components such as Linac, BT, QCS,
Power supply for magnets, etc. Present attainable Ecm is 11.24GeV, limited by
e- Linac and e+ BT magnets. �– In order to inject the electron beam to HER at the required energy for 12 GeV
operation, there must be huge reinforcement of Linac (replacement of S-bandwith C-band, 7.571 -> 8.6 GeV; current estimation of cost is about 24 OkuYen).�
– From the viewpoint of the cost and labor, energy ramp-up of HER is supposed
to be more realistic, so we will study its possibility. �– Development of C-band units for Linac will also be promoted. �

Overview of construction status�

K. Akai (KEK)�

19�

Request from Belle II regarding high energy running of SuperKEKB�
November 8, 2011�
Dear Akai san, Enomoto san and Koiso san,�( cc to Oide san )�
On behalf of the Belle II collaboration, we would like to ask you and the KEKB accelerator team toinvestigate the maximum possible obtainable center of mass energy of Super KEKB and the issues
associated with achieving it.�A reason for this request is a recent discovery by Belle of the two charged bottomonium resonances in theUpsilon (5S) decays. This remarkable result likely means that we now enter a new era of heavy
quarkonium physics for which Super KEKB can provide unique opportunities. In particular, based on
Heavy Quark Effective Theory, we expect the existence of exotic bottomoinum states near and above
the thresholds of B*B*bar, Upsilon (5S).�
These states, however, cannot be produced in a single-pion transition from Upsilon (5S) due to G-parity
conservation rule. The only possible way to produce them can be by the emission of a rho meson fromhighly excited Upsilon states, and therefore, the total CMS energy of about 12 GeV is necessary. We
expect meaningful physics results with running at this high energy even in case of significant
luminosity degradation.�
Hence, we request Super KEKB group kindly provide us with the information regarding its feasibility andthe issues associated with high energy running. It is our strong wish to understand the limiting factorsof high energy running and to work with you to solve the potential problems if possible.�
We thank you very much in advance and look forward to hearing from you.�
Peter Krizan�
Spokesperson, the Belle II collaboration�
Hiroaki Aihara�
Chair of the Executive Board, the Belle II collaboration�

Overview of construction status�

K. Akai (KEK)�

20�

Limitations for Higher Ecm�e-­‐	
  Linac	
  (present	
  limit)	

e-­‐	
  BT	
  magnets	
 QC1E(HER)	
  90%	
  quench	
  limit	   	

4.364	
  GeV	  @	
  860A	
  	
  

11.6	
E={7.32,4.18}

11.8	
 12	
  GeV	
A	

11.05	
  GeV;	
  original	
  Ecm,	
  max	
E	 11.24	
  GeV;	  	
  present	
  a^ainable	  Ecm,	
  max	  	

Overview of construction status�

Power	
  supply	
  of	
  LER	  main	
  dipoles 	K. Akai (KEK)�

QC1P(LER)	
  90%	
   	

B	
C	

e+	
  BT	
  magnets	
  D	

(with	
  replacing	
  power	  supplies)	

21�

Design Issues to be fixed�• Optics and IR design�– Both sides of IR (300m Tsukuba) vacuum components and magnets
production scheduled in FY2012. �– QCS fabrication should start in FY2012.�

• Sextupole scheme�– Rotation sextupole magnets are required in LER. �– In HER, normal sextupole and independent skew-sextupole may be OK at T=0.�

• BG, Collimation system, radiation shield�
– BG estimation, movable masks R&D, investigating radiation going on.�• Requirement for BPM detectors�
– Specification and how many at T=0?�

• Injection scheme�
– Synchrotron injection in HER? �• Abort system�– Possible scheme to abort nano beam.�
Overview of construction status�

K. Akai (KEK)�

22�

Budget�• Budget�– Total construction budget is 314 Oku-Yen for Rings, Injector, and Belle-II.�
– Most of the budget comes year-by-year based.�
– Operation budget is expected in FY2014 and later.�

FY2010	

FY2011	FY2012	

FY2013	Very	
  Advanced	
  Research	
  SP	
  (100	
  Oku-­‐Yen)	
  	

FY2014	

FY2015	

FY2016	
  SuperKEKB	
  commissioning	

Other	
  budgets	
  for	  construcEon	
  (214	
  Oku-­‐Yen)	
  	
OperaEon	
  budget	
  (conEnues	
  -­‐	  -­‐	  -­‐	
  )	
  	

We	
  are	
  here	

Unit: Oku-Yen (˜1.2M$)�

FY2010	

FY2011	FY2012	

FY2013	

FY2014	

Total	VARSP�

75.0	

10.5	

14.5	

0	

0	

100.0	

Others�

0	

41.6	

40.2	

61.6	

46.7	

190.0	

Facility�

0	

4.5	

12.4	

7.2	

0	

24.1	

Total�

75.0	

56.6	

67.1	

68.8	

46.7	

314.1	

Status�Supplied	

Overview of construction status�

Supplied	
 Submi^ed	
  to	
  the	
  

Diet	

To	
  be	
  submi^ed	
   To	  be	
  submi^ed	
  to	
  the	
  Diet	to	
  the	
  Diet	K. Akai (KEK)�

23�

Human Resources�
• HR of KEK staff�
– Change of permanent staff members from the last MAC�• Apr. 2011: One retired. Three newly hired. Two joined from other groups.�
• July 2011: One joined from other group.�
• Apr. 2012: Two will retire. Three expected to be newly hired. Some join?�

– Senior staffs after retirement�
– Young members at term positions�• Other helps�– Collaborations going on�
– KEKB operation crew (company persons) to help construction work�• Situation of short HR seems getting better�
Date	

Status	

Needed	  FTE	

Available	
  FTE	  of	
  permanent	
  staﬀs	Non-­‐permanent	
  staﬀs	
  added	Dec.	
  2010	  under	  construcRon	

77	

56	

61	

Apr.	
  2011	  under	  construcRon	

77	

60	

66	

Apr.	
  2012	

under	  construcRon	

77	

62	
  +some?	

67	
  +	
  some?	
  	Overview of construction status�

K. Akai (KEK)�

24�

Vacuum system�• Fabrication of vacuum components -> Talk by Y. Suetsugu �– Aluminum ante-chamber beam pipes for LER arc sections (700 pieces, 2km
length) on going in FY2011. �– Bellows and gate-valves for arc and wiggler sections to be completed soon.�
– Copper beam pipes for wiggler sections in LER and HER to be completed soon.�
– Beam pipes, bellows and gate-valves in Tsukuba straight section for both rings
to be ordered in FY2012 and 2013. �– Movable masks, SR and X-ray monitor chambers will be made in FY2013 and2014. Currently, R&D is going on.�– Replacement of some HER components for higher beam current before or after
T=0 depends on budget. �• Baking and TiN coating system -> Talk by K. Shibata�– Deck for vacuum work in Oho has been rebuilt after old AMY detector of
TRISTAN was removed. �– The first baking system and the first TiN coating station has been built in thevacuum deck. �– More sets of baking and coating stations will be built soon.�

Overview of construction status�

K. Akai (KEK)�

25�

LER beam pipe fabrication @BINP�

Overview of construction status�

K. Akai (KEK)�

26�

TiN coating machine�

TiN coating machine (1st vertical type) in
Oho experimental hall�Overview of construction status�

K. Akai (KEK)�

27�

Magnet system�-­‐>	
  Talk	  by	
  H.	
  Iinuma	• Fabrication of magnets�
– Fabrication and field measurement of LER 4m dipole magnets is going on. They
will be installed in tunnel in the first half of FY2012. �– Half-pole and single-pole wiggler magnets, LER V-steering magnets, some of Q
magnets on going in FY2011. �• Fabrication of power supplies for magnets�
– Power supplies for main dipole magnets and wiggler magnets are going on in
FY2011. �– Power supplies of medium and small power will be ordered in FY2012 or later.�
– Power supplies for DR: some are ongoing, others will be in FY2012.�

• Alignment and tunnel measurement�
– Measurement after the earthquake showed significant movement of tunnel. �– Introducing GPS system and investigating the ground (boring, etc.) going on.

Overview of construction status�

K. Akai (KEK)�

�

28�

Dismantle Tsukuba straight section�
Removed power cables�

Dismantle both sides of IR(D1 and D2) done.�
Magnets and cables have been removed. �
Old base plates were removed, and thefloor has been cleared up.�Overview of construction status�

K. Akai (KEK)�

29�

LER new 4m dipole magnets�
Field measurement set up �

The first goods delivered to KEK. �

Overview of construction status�

Install test in the outer LER over existing
magnets in the inner HER.�

K. Akai (KEK)�

30�

Interaction Region�
• A lot of critical issues�
––––Optics design�QCS design and fabrication�
IR hardware design and assembly�
Background�• Storage beam�• Injection transient, blow-up, mask, IR aperture�• Vacuum pressure at large beta (beam-gas)�

– Error tolerance at local chromaticity correction and correction method�– Ripple of power supply�– Collision feedback�• Will be presented in the following talks today:�
–
–
–
–
–
–

Dynamic aperture and IR modeling (A. Morita)�
Error Tolerance and Optics Correction (H. Sugimoto)�
IR Magnets (N. Ohuchi)�
Beam Background (H. Nakayama)�
IR Vacuum Chamber and Assembly (K. Kanazawa)�
Collision Feedback (Y. Funakoshi)�

Overview of construction status�

K. Akai (KEK)�

31�

RF system�• Upgrade items�
– Change to 1 klystron to 1 ARES cavity scheme to increase beam power�• Rearrange ARES cavities�
• Change input coupler of the ARES to increase coupling β from 3 to 6�
• Add klystrons, power supplies, HPRF and LLRF�

– Cure for increasing HOM power -> Talk by Y. Morita�– Develop new LLRF -> Talk by T. Kobayashi�• Damaged LLRF in D5 by the earthquake will be replaced with new ones.�

– Develop Damping Ring Cavity -> Talk by T. Abe�
– Replace old components with new ones (klystrons, power supplies, etc.)�

Overview of construction status�

K. Akai (KEK)�

32�

OHO	

D4	
1	

C	

2	

B	

KEKB	
2	

1	

C	
 E	

E	

2	

A	

A	

B	

FUJI	

D7	

D5	

2	

2	

D	

C	

B	

A	

1	

2	

2	

A	

D10	

D8	
B	

C	

D	

E	

2	

NIKKO	
2	

2	

D	
 C	
 B	
 A	

D11	
 Lower	  2	

power	
1	

A	
 B	
 C	
 D	
 E	
 F	

HER	
LER	

Add	
  3	
  power	  supplies	
  (done)	
  	
OHO	

D4	
2	

H	

2	

2	

G	
 D	
 C	
 B	
 A	

SuperKEKB	
  (commissioning:	
  T=0)	
2	

1	

A	
 B	
 C	
 D	
 E	
 F	

E	

2	

2	

FUJI	

D7	

D5	

2	

D	

2	

C	

B	

A	

D10	

D8	

A	

1	

2	

2	

B	

C	

Replace	  4	
  old	
  VP-­‐klystrons	  in	
  D10	
  with	  new	
  klystrons	

D	

E	

2	

NIKKO	

2	

D	
 C	
 B	
 A	

2	

D11	
2	

A	
 B	
 C	
 D	

5	
  spare	
  klystrons	
  to	
  be	
  installed	
  this	  year	Add	
  2	
  caviRes	
  (done)	
  	
Relocate	
  6	
  caviRes	
  HER-­‐>LER	  (done)	
  	
Klystron,	
  HP&LLRF	
  system	Overview of construction status�

4	
  caviRes	
  to	
  be	
  removed	
  this	  year	2	

Type	
  “A”	
  power	  supply	
  (for	  two	
  klystrons)	

1	

Type	
  “B”	
  power	  supply	
  (for	  one	
  klystron)	
K. Akai (KEK)�

ARES	
  cavity	SC	
  cavity	Crab	
  cavity	
33�

Relocate ARES cavities in D5�
To convert 6 ARES cavities from LER to HER.�
(KEKB-D5): 6 cavities in LER�On the way�Done�

3 cavities in LER�

3 cavities
moved to HER�
6 cavities �
moved to HER (done)�

Overview of construction status�

K. Akai (KEK)�

34�

More	  reinforcement	
  of	
  RF	
  for	  design	
  beam	  current	
  (aBer	
  T=0)	

add	
  2	
  more	  klystrons,	
  HP&LL,	
  	
  
add	
  1	
  more	  	
  power	  supply	
OHO	
2	

D4	

2	

2	

2	

H	
 G	
 F	
 E	
 D	
 C	
 B	
 A	

add	
  2	
  more	  klystrons,	
  HP&LL,	
  	
  
add	
  2	
  more	  	
  power	  supply	

D5	
2	

2	

A	
 B	
 C	
 D	
 E	
 F	

F	
 E	

2	

2	

Klystron,	
  HP&LLRF	
  system	

FUJI	

D7	
2	

D	

2	

C	

B	

D8	

2	

A	

A	

2	

Type	
  “A”	
  power	  supply	
  (for	  two	
  klystrons)	

1	

Type	
  “B”	
  power	  supply	
  (for	  one	
  klystron)	

B	

C	

add	
  1	
  or	
  2	
  SCC	  add	
  2	  klystrons,	
  HP&LL	
D10	

2	

2	

D	
 E	
 F	

ARES	
  cavity	

2	

NIKKO	

2	

D	
 C	
 B	
 A	

SC	
  cavity	

2	

D11	
2	

2	

A	
 B	
 C	
 D	
 E	
 F	

Crab	
  cavity	The	
  reinforcement	
  aNer	  T=0	
  depends	
  on	
  requirement,	
  machine	
  performance	
  and	
  budget.	

Overview of construction status�

K. Akai (KEK)�

35�

Monitors, Control, Beam Transport�
• Present status�
– R&D on various monitor components including BPM detectors, bunch-by-bunch
feedback system, X-ray monitors is going on.�– Fabrication of BPM electrodes, amplifiers for FB, etc. is going on.�– Design of beam abort system in progress. �• Will be presented in the following talks:�
–
–
–
–
–

Beam diagnostics, Feedback systems (M. Tobiyama)�
Photon Monitors (J. Flanagan)�
Synchrotron Injection (T. Mori)�
Beam Abort System (T. Mimashi)�
Control and Timing System (K. Furukawa)�

Overview of construction status�

K. Akai (KEK)�

36�

Reinforce Cooling system�• Need for increasing cooling power�
– Three times for vacuum system (5MW→16MW).�
– 1.5 times for magnet system (10MW→16MW).�

• How to do this�– Four new buildings for cooling system will be built in FY2012~2013. �– Cooling tower of existing system will be reinforced for higher current.�
– Replace existing cooling pipes in tunnel with larger aperture ones to increasewater flow. �• Issue�– Replacing cooling pipes is necessary almost all around the ring. This may
interfere various works in the tunnel such as installing magnets and beam
pipes. Furthermore, some of the existing or newly installed magnets may need
to be temporarily moved. This may cause schedule delay. �• Measure�– Possible ways of doing this work with minimum interference are now being
studied by various contractors. Design of cooling system and piping is also
ongoing. They will give reports by the end of this March to help us decide theway and schedule of tunnel work. �

Overview of construction status�

K. Akai (KEK)�

37�

12M	

New	
  buildings	
  for	
  cooling	
  system	New	
  buildings	
  for	
  power	  supply	
3M	

9M	

To	
  build	
  6M,	  an	
  old	
  building	
  for	  PS	  main	  ring	
  power	  supply	
  will	  be	
  dismantled.	
  	

Overview of construction status�

6M	

K. Akai (KEK)�

38�

Damping Ring�• Design�
– Optics design is almost fixed. �– Remaining issue is to determine beam pipe cross section size from the view
point of CSR and acceptance. -> Talk by H. Ikeda�

• Components�
– Fabricating magnets and power supplies are ongoing as scheduled. �– Test beam pipes (aluminum, ante-chamber) is being made. Mass production
will be planned in FY2012. �– R&D of DR cavity is going on. A prototype cavity will be completed in FY2011,
and will be high-power tested soon. �• Tunnel and buildings�
– See, next slide.�

• Issue�– Since tunnel construction delayed for six months due to the earthquake,
installation of components will start only one year before T=0. Schedule in
FY2014 will be very tight with installation, cabling and piping, system check,etc. �
Overview of construction status�

K. Akai (KEK)�

39�

Damping Ring�DR tunnel construction delayed for six months due to the earthquake.�
Installation can start after the inspection of buildings, only one year before T=0.�

very	
  Rght	  schedule	
  
	
  in	
  FY2014	

Overview of construction status�

K. Akai (KEK)�

40�

Summary �• The earthquake caused some delay and additional
works for SuperKEKB construction, but we manage torecover to be in time for T=0. �• Design work and construction work are going on at thesame time in consistent ways. But time limit for somecritical designs will come soon. �• So far, budget is supplied as planned, except for thedelay due to the earthquake. �• Shortage of human resources is getting better. �• Construction is well ongoing, prioritizing for T=0.�

Overview of construction status�

K. Akai (KEK)�

41�