Recovery of Linac after the Earthquake
SuperKEKB Accelerator Review, 2012. 2. 20

A. Enomoto
KEK e-/e+ Injector Group

2011. 3. 11

This is beginning of the earthquake.
It shook for nearly three minutes.
It was a long and strong earthquake we never experienced.

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 20122

This is the beginning of the earthquake.
Long (~3 minutes) and strong (6 lower in Japanese scale)
earthquake we never experienced!
~0.2 s (~5 Hz)

Tsukuba

328.8 gal

342.9 gal

Tsukidate
K-Netによる加速度の観測(防災科学技術研究所提供）

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 20123

This is the beginning of the earthquake.
Long (~3 minutes) and strong (6 lower in Japanese scale)
earthquake we never experienced!

5 minutes

14:47

14:52

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 20124

Damage of equipment in the 600-m long Tunnel
Plan

Elevation0m
Tunnel floor is 3.75m deep

Pile depths are from -35.45 m to -38.8 m.

-50 m

Klystron Gallery

N >50
0

50

Tunnel

N value: hammering frequency when an iron rod penetrates theground by 30 cm with free falls of a 63.5 kg hammer from 75 cm
high. （Ｎ値：鉄管に重さ63.5kgのハンマーを75cmの高さから自由落下させて30cm地面に貫入するのに必要な打撃回数）

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 20125

Drop-down of a Quadrupole Triplet

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 20126

Break-down of the entire Linac Vacuum

VacuumManifolds

Gate-Valves loosened without gas pressure.

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 20127

Destroyed BPMs

Torn bellows

Damaged bellows
SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 20128

Destroyed Girders

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 20129

Longitudinal Shifts of the Accelerator~2 cm~10 cmSuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201210

~6 cmTransverse Shifts

SlippedSuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201211

Incredible Destructive Force

Anchor bolt

StopperSuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201212

Inflow Water through Tunnel Joints

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201213

Damage of equipment in the Klystron Gallery

Klystron Gallery

TunnelSuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201214

We have ~60 RF UnitsSLED(RF Pulse Compressor)

RF Windows
50-MW Klystron

Waveguides
3-dB Hybrid(power divider)

Pulse modulator
Step-up Trans

45-kV Feeder Cable

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201215

45-kV Pulse Feeder cable
SLED(RF Pulse Compressor)

RF Windows
50-MW Klystron

Waveguides
3-dB Hybrid(power divider)

Pulse modulator
Step-up Trans

45-kV Feeder Cable

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201216

45-kV Pulse Feeder cable
SLED(RF Pulse Compressor)

RF Windows
50-MW Klystron

Waveguides
3-dB Hybrid(power divider)

Pulse modulator
Step-up Trans

45-kV Feeder Cable

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201217

45-kV Pulse Feeder cable
SLED(RF Pulse Compressor)

RF Windows
50-MW Klystron

Waveguides
3-dB Hybrid(power divider)

Pulse modulator
Step-up Trans

45-kV Feeder Cable

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201218

45-kV Pulse Feeder cable
SLED(RF Pulse Compressor)

RF Windows
50-MW Klystron

Waveguides
3-dB Hybrid(power divider)

Pulse modulator
Step-up Trans

45-kV Feeder Cable

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201219

45-kV Pulse Feeder cable
SLED(RF Pulse Compressor)

RF Windows
50-MW Klystron

Waveguides
3-dB Hybrid(power divider)

Pulse modulator
Step-up Trans

45-kV Feeder Cable

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201220

45-kV Pulse Feeder cable
SLED(RF Pulse Compressor)

RF Windows
50-MW Klystron

Waveguides
3-dB Hybrid(power divider)

Pulse modulator
Step-up Trans

45-kV Feeder Cable

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201221

Damage of equipment in the Klystron Gallery

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201222

Recovery of Linac

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201223

Discuss how we should address this Disaster!
Daily Meeting at Linac LoungeMe

Day and days pretty cold without electricity …..
SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201224

Start with Visual Check of Earthquake Damage

Keep All Accelerator Structures ASAP with Dry N2

Recovery of downstream 3/8 Linac ASAP for PF

Recovery & Upgrade of upstream 5/8 Linac forSuperKEKBSuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201225

We have ~60 RF units.
Keep All Accelerator Structures ASAP with Dry N2 !

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201226

Bad Atmosphere before April 25
Daily Morning Work of Drainage

Humid without Ventilation !

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201227

Dry N2 Purge done after 2 weeks
Visual Check
Replace Broken Equipment
Rough Evacuation up to ~1 Pa
Replace Heavy Leak Equipment

Purge Accelerator
with Dry N2

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201228

“Recovering 3/8” Started on March 28

Upstream 5/8

Downstream 3/8(~3 GeV)SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201229

3/8 Vacuum Recovery Needed 1 month
Establish Beamline
Evacuation
Leak Test
Replace Leak Equipment
Leak Test

Baking >8 h
Start Ion Pumps

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201230

BPMs Repaired in KEK Workshop
Weld new bellows

30/95 BPMs broken
Check signals

Remove broken bellows(Photos by T. Suwada)

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201231

Oscillation Analysis(Data by R. Sugahara )3.5 HzSuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201232

Oscillation Analysis(by K. Kakihara)

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201233

Reinforced Accelerator Girders
Against expected strong aftershocks

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201234

Survey and Alignment

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201235

Acc_S5U1

Acc_S4U1
1.0

1.0
Acc2_dX1
Acc2_dX2

RMS1 = 0.041mm
RMS2 = 0.081 mm

Only large discrepancy corrected
Acc_S3U2

Acc2_dX1
Acc2_dX2

RMS1 = 0.157mm
RMS2 = 0.148 mm
0.5

0.5

dX1_1

1.0

RMS = 0.217mm

S4 U1

Acc_S4U2

0.0

1.0

0.5

S3 U2

0.0

Acc_S3U3
1.0

-0.5

0.5

0.5

0.0 0

Acc2_dX1
Acc2_dX2

RMS1 = 0.051mm
RMS2 = 0.073 mm

S4 U2

4,000

6,000

Acc_S3U4
Y (mm)

8,000

S3 U3

0.5

0
RMS1 = 0.154 mm
RMS2 = 0.298 mm

2,000

S4 U3

Acc1_dX1
6,000Acc1_dX2

4,000

Acc_S4U4
Y (mm)ーY (mm)

Acc_S3U5

0.0

10,000

S3 U4

2,000

4,000

6,000

8,000

#2
2,000

0

4,000

S4 U4
#7

6,000

8,000

Acc_S3U6

0

2,000

4,000

0.0

Y (mm)

6,000

S5 U4
8,000

10,0004,000

Acc2_dX1
6,000 Acc2_dX2

8,000

Acc_S5U5
1.0

RMS1 = 0.066mm
RMS2 = 0.107 mm-4,000-1.0-2,000-0.5-2,000

0

2,000

4,000

2,000

4,000

0
RMS1 = 0.121mm
RMS2 = 0.165 mm

2,000
Y (mm)

0.5

Y (mm)-4,000-2,0000
Y (mm)

Acc_S4U6

0.0

-0.5

8,000

-1.0

1.0

1.0

Acc1_dX1
Acc1_dX2

RMS1 = 0.131mm
RMS2 = 0.138 mm

10,000

Acc2_dX1
Acc2_dX2

0.5

S3 U5

Acc1_dX1
Acc1_dX2
6,000

0.5

Y (mm)#1

Y (mm)

0.0

4,000

-1.0

1.0
10,000

S5 U3

-0.5

#8

-0.5

0

2,000

#8

Acc_S4U5

Acc2_dX1
Acc2_dX2

-0.5

0.5

Acc_S5U4-1.0
RMS1 = 0.263mm-2,000 RMS2 = 0.212 mm
00.0

Y (mm)

Guess

#6

-1.0
0.0

8,000

#7
#5

-0.5

RMS1 = 0.061mm
RMS2 = 0.056 mm

Acc2_dX1
Acc2_dX2

Guess

ー

#2

0.0
#1

1.0

10,000

Acc1_dX1
Acc1_dX2

#5
#6

0.5

8,000

8,000

1.0

RMS1 = 0.154 mm
RMS2 = 0.298 mm

0.5
-1.0

S5 U2

6,000

RMS1 = 0.270mm
RMS2 = 0.304 mm

1.5

0.5

6,000

4,000

Acc_S5U3
Y (mm)

Acc_S4U4

1.0-1.0-2,000
0.0

-0.5

4,000

2,000

-0.5

1.0

2,000

0

0.0
1.0

Acc2_dX1
Acc2_dX2

0.5

1.0
-0.5

0

-1.0

10,00010,000

Acc1_dX1
Acc1_dX2

RMS1 = 0.078mm
RMS2 = 0.101 mm

8,000

RMS1 = 0.060mm
RMS2 = 0.145 mm

-0.5

1.5
0.0

6,000
Y (mm)

0.5

2,000

4,000

Acc_S4U3

1.0

-1.0
0

2,000

Acc1_dX1
Acc1_dX2

RMS1 = 0.233mm
RMS2 = 0.215 mm

-0.5

-1.0

-0.5

1.0

Acc1_dX1
Acc1_dX2

RMS1 = 0.099mm
RMS2 = 0.122 mm

S5 U1

Acc_S5U2

0.0

S4 U5

S5 U5

0.0

Acc1_dX1
Acc1_dX2

RMS1 = 0.118mm
RMS2 = 0.089 mm

Acc_S5U6

Acc1_dX1
Acc1_dX2

-0.5
1.0

-0.5

0.5
0.5

-1.0
0

2,000

0.0

4,000

Acc_S3U7

S3 U6

6,000
Y (mm)

8,000

10,000

RMS1 = 0.416mm
RMS2 = 0.482 mm

-1.0
0

2,000

4,000

0.0

S4 U6

6,000

Acc_S4U7
Y (mm)

1.0

8,000

10,000

-1.0
0.5

0

2,000

Acc2_dX1
Acc2_dX2

RMS1 = 0.132mm
RMS2 = 0.102 mm-0.5

Acc_S3U8

0.5

0RMS1 = 0.108mm
RMS2 = 0.125
mm
2,000

Acc_S4U8

S3 U7

6,000
Y (mm)

1.0

8,000

1.0
-0.5

1.5

Acc1_dX1
Acc1_dX2

4,000

10,000-1.0-2,000 RMS1 = 0.228mm
0
RMS2 = 0.224 mm
0.0

2,000

S4 U7

Acc1_dX1
6,000Acc1_dX2

4,000
Y (mm)

8,000

0.5
-1.0

1.0

0

2,000

4,000

6,000
Y (mm)

-0.5

-0.5

0.5

0.5

S3 U8

-1.0

0.0

0

2,000

4,000

6,000

8,000

0.0

-1.0

10,00010,000

Acc2_dX1
Acc2_dX2

RMS1 = 0.108mm
RMS2 = 0.172 mm

0.5

0.0

8,000

1.5
0.0

1.5
-1.0

S5 U6

6,000
Y (mm)

Acc2_dX1
Acc2_dX2

RMS1 = 0.082mm
RMS2 = 0.178 mm

-0.5

4,000

Acc_S5U7

1.0

0

2,000

4,000

S4 U8

6,000

0.0

Y (mm)Y (mm)

8,000

10,0008,000

10,000

S5 U7

-0.5
0

2,000

4,000

6,000

8,000

10,000Y (mm)

-0.5

-0.5
0

2,000

4,000

6,000
Y (mm)

8,000

10,000-2,000

0

2,000

4,000

6,000

Y (mm)(Data by R. Sugahara and H. Iinuma)
SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201236

The rack was re-installed(Photos by K. Furukawa)

SuperKEKB Accelerator Review, Atsushi
Enomoto, 9:00 - 9:40, February 20-22, 201237

RF Conditioning

Trip no.
Voltage decreased for Commissioning

1st week

2nd week

3rd week(Data by Y. Yano)
SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201238

Summary of the recovery process from Earthquake to Linac commissioning
ActionTunnelWeek

May

Visual Chk,
N2-purge

Gallery

Requirement
OthersElectric

VisualCheck

Visual
Check

20 kW

21 - N2-purge

Kly/ Thy

PPS

20 kW

28-

Vacuum

Kly rplc.

60 kW

04 - Vacuum

Kly rplc.

75 kW

11-

Vacuum

Diode
Test

18-

VacuumMarch 14 -

April

Work

Trigger Sys

90kW
2 MW night

Mechanic

Building

Crane

Water (kly)
Gas

90 kW

25-

RF aging(Apr28-)

2 MW

02-

RF aging

2 MW

10-

Cmmssn.

2 MW

Water
(Sec3-5), Air

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201239

Injection to PF resumed ~2 months after the Earthquake

PF Top-Up Injection (450.0 +-0.2 mA)

On May 16 injection started for PF, June 1 for PF-AR.
SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201240

Recovery and Upgrade of the Linac

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201241

“Recovering 5/8” Started on June

Upstream 5/8

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 2012

42

Status of Upstream (5/8 Linac Sectors)
Sector A, B

Sector C

Sector 1, 2•

The upstream part of the linac had been separated by a concreat shieldwall in 2009 to upgrade Linac while continuing beam injection for PF and
PF-AR.
SuperKEKB Accelerator Review, Atsushi
Enomoto, 9:00 - 9:40, February 20-22, 201243

Accelerator Units
Damaged Beam-line

Broken Vacuum Manifold
ClosedRepaired

Vacuum Cap••

Vacuum recovery of the upstream accelerator was initiated on June andcompleted by the end of October.
However, the each accelerator units are isolated in vacuum; the beamline components such as bpms are not yet installed.
SuperKEKB Accelerator Review, Atsushi
Enomoto, 9:00 - 9:40, February 20-22, 201244

High-Power RF Tests•

High-power RF test for the upstream accelerator units were done in
November and December; and fortunately, no serious problems were notfound!

SuperKEKB Accelerator Review, Atsushi
Enomoto, 9:00 - 9:40, February 20-22, 201245

Beam-line Components

Broken Bellows••

The magnet dropped was temporarily placed on the floor.
The broken bpms were all removed and already repaired.
SuperKEKB Accelerator Review, Atsushi
Enomoto, 9:00 - 9:40, February 20-22, 201246

Accelerator Girders
Re-Positioning
SlippedRe-Positioning

Put on Square Logs••

The accelerator units were roughly corrected to their original positions.
The broken girders were temporarily put on square logs.
SuperKEKB Accelerator Review, Atsushi
Enomoto, 9:00 - 9:40, February 20-22, 201247

Inflow Waters

Just after the quake

2011.12 Sector-1

2011.12 Sector-1 End

2011.12 Sector-2 End

2011.12 Switchyard-3 ~ PF-BT•

Inflow water from the tunnel joints exceeded 50 t per day after theearthquake; however, by grouting materials into joints several times it has
been reduced less than 2 t per day since autumn, 2011.
SuperKEKB Accelerator Review, Atsushi
Enomoto, 9:00 - 9:40, February 20-22, 201248

Current status of Injector Group• The earthquake caused heavy damage to Linac.
• But the earthquake gave us an energy to overcome
the disaster and more.
• We also got some recovery budget as well as energy.
• The major goals and timeline to the SuperKEKB
Injector Upgrade are not changed.
– RF gun development (Mitsuhiro Yoshida) 21 Feb. 13:00 – Positron source upgrade (Takuya Kamitani) 21 Feb. 13:40-

SuperKEKB Accelerator Review, Atsushi
Enomoto, 9:00 - 9:40, February 20-22, 201249

Thanks for Attention.

SuperKEKB Accelerator Review, Atsushi Enomoto, 9:00 - 9:40, February 20-22, 201250