Neutrino target station at JPARC

Contents•Introduction •Radiation (detail: talked by Oyama)•Support system & maintenance •Cooling system•Schedule

Yoshikazu Yamada (KEK)Y.Hayato, E.Hirose, A.K.Ichikawa, T.Iwashita,

T.Kobayashi, S.Koike, T.Miura, H.Nakano, Y.Oyama, N.Sato, T.Suzuki, Y.Yamanoi

4th International Workshop on the Neutrino Beams and Instrumentation

November 11, 2003

1st Horn 2nd Horn 3rd Horn

Fast-extracted proton beam line

Neutrino beam line and target

Target Station

Decay volume

Beamdump

50GeV PS

Target•Carbon target: 30mm-,900mm-L•beam size: σr ~6mm

beam to SK

0.75MW beam

Neutrino target station22m

Iron shield

Helium container

Machine room

Service pit

Storage for radioactive material

11m

33m

Iron shield

Concrete blocks

40 ton crane

Target & 1st horn

Beam window

2nd horn 3rd horn

Final focus

Decay volume

Concrete shield

Beam window

Ground level

Baffle

22m

Iron:2.2m

concrete wall : 20cm-t

Iron:1.5mIron

:1.5

m

Concrete:4.4m

Concrete:1m

< 12.5Sv/h@floor of surface building

< 0.25

Sv/h

@ou

t of the con

trol areafence

Concrete: 4.5m

Con

crete:3.6m

Shielding and radiation level

< 5mSv/h@boundary of concrete

0.75MW operation

detail Oyama’s talk

confirmed by MARS

Residual dose

Aluminum wall ~0.65(0.17) Sv/h

Upper iron shieldOuter : 22(16) Sv/hInner : 0.56(0.42) Sv/h

Floor of service pit~0.1(0.07) μSv/h Service pit

Machine room

One (seven) day cooling after one year operation

(by MARS)

detail Oyama’s talk

Side view of target area

Baffle

Target+1st horn 2nd horn

3rd horn

Iron shield

Concrete shield

Iron shield

Concreteshield

Service pitBus bar

Aluminum wall

Bus bar Bus bar

Win

dow

Helium container

Support of hornCollimator

for DV

15m

2.2m

1m

Front view of target area

1st horn

Iron shield

Concrete shield

Iron shield

Concrete shield block

Service pit

Transformer

Aluminum wall

Bus bar

Helium container

Support of horn

Concrete shield block

Area for ad

dition

al sh

ields for 4M

W

storage for radioactive

material

Underground machine room

3m6m

1st horn

Iron shield

Iron shield

Bus bar

Helium container

Concrete shield block

Helium container•3m(W)6m(H)15m(L), 5cm-thick iron wall •Filled by Helium gas (1-atm, 130m3, ~99%) •Reduce Tritium production : ~1/25?

• ~30mb for Air, ~1.2mb for He

•Tritium production after 200 days operation:

Air:800Bq/cm3, He:30Bq/cm3

•Ventilation time after 200 days operation

Air:110days, He:5days

(ventilation: 8000m3/hour, regulation:5mBq/cm3)

•Reduce corrosion by NOx : ~1/100?•20cm thick Aluminum wall in target area

reduce surface dose by ~1/10 at maintenance

Support system of horn

Support of horn

Iron shield

Concrete shield

support alignment

support hear

Exchange of the target/ horn

storage of radioactive materials

top view

Cross-sectional view

•Upper Iron and concrete shields are removed.

•Highly radioactivated target/horn are moved under ground-level and kept in the storage of radioactive materials for several years.•New target/horn are installed and shields are installed.•All works should be done remotely.

Ground level

Exchange of the target

A) If horn is broken, scrap target and horn.B) If target is broken;

1) Scrap target and horn. or2) Replace broken target with new one in the horn

i) at the storage for radioactive material. orii) at the beam line.

All works should

be done remotely.

Heat load : ~170 kW on Aluminum, 40kW on Iron

Heat load on Al-wall/Fe-shield

En

ergy

dep

osit

(W

/m)

Aluminum

Fe(1st 20cm)

Fe(2nd 20cm)

Iron shield

Iron shield

Concrete shieldMARS

Water pipe for Aluminum wall

(option for 4MW)

Cooling for Aluminum wall

Temperature rise in Al wall QAl=17/8(kW/m),L= 3/2(m),

A ｌ =240(W/mK), A=0.2(m2)

)(332/

KA

LQT

Al

Al

Iron shield

Iron shield

Concrete shield

Water flow =170(kJ/s)/4.2(J/g/K)/10(K)/8

=30(Litter/min.)(8)

1-inch tubeRe=32000, k=4860(W/m2K),

T=3.7(K) 、 P=0.11(kg/cm2)

Radio activity of water Oyama’s talk

Air cooling surface for iron shieldOuter surface (Default)Middle surface (Option for 4MW)Inner surface (Option for 4MW)

Cooling for Iron shieldWater pipe for upper iron shield

Iron(1m-t)

heat at rI

cooled at rO

)(27)(2.21)(5.5

2ln

2

KKK

kr

Q

r

rQT

OO

Fe

I

O

Fe

FeO

Temperature rise in iron shield QFe=4(kW/m), Fe=80(W/mK),

rI =1.5(m),rO =3.0(m), kO=10(W/m2K)

Iron shield (Duratec?)

Iron shield

Concrete shield

Concrete shield

Air flow: 40000(J/s)/1.0(J/g/K)/10(K) =200(m3/min)Radio activity of air Oyama’s talk

Cooling system for Al wall

150kW

1.15m3

170kW 0.06m3

32C360 litter/min

Buffer tank

32C

Chiller

50kW

Chiller

50kW

Spare chiller50kW

Underground machine room

(TP+2.7m)

Underground machine room for beam dump

(TP?m)Final focus Section(TP-1.7m)

Machine building for beam dump

(TP?m)Primary cooling systemfor Decay volume(Target side)

Primary cooling systemfor Decay volume(Dump side)

Buffer tank

Pump

Pump

Decay volume

Primary cooling water linefor magnet(FF section)

Magnet DP tank

Disposalline

Water

Disposal line

800m3/20days

30C540 litter/min

35C

30C3000 litter/min

80C

30C

32C360 litter/min

35C

35C

32C

23C120 litter/min

30C480 litter/min

Primary cooling systemfor Aluminum wall andupper/collimator ironshield

35C

45C 240 litter/min

for target

for 1st horn

20kW0.1m3

30 litter/min

10kW0.2m3

30litter/min

10kW0.2m3

30litter/min

10kW0.2m3

30litter/min

30 litter/min

30 litter/min

30 litter/min

60 litter/min

150 litter/min

Buffer tank

240 litter/min

Pump

Chiller

50kW

Chiller

50kW

Spare chiller50kW

Underground machine room

(TP+2.7m)Surface building of target station(TP+10.8m)

2nd machine building

(TP+9.3m)

cooling system for target/horn

Third water cooling system Primary water cooling system

Secondary water cooling system

for 2nd horn

for 3rd horn

water line

Secondary

Disposal to buffer

tank for DV

Pumps

Filters for radioactivity

Degassing system

Water

Buffer tank

Underground machine pit

(TP+2.7m)

Service pit

(TP+2.7m)

Target area

(TP-1.7m)

Target20kw1 litter

Primary cooling system for target

30litter/min.

in experiment

in maintenance

Circulation in experiment

Always ventilating

Ventilation inmaintenance

StackHEPAfilter

Filter for salt

Cooling unit

Fresh air

Air circulation/ventilation system

Circulation in experiment

Building

Underground machine room

Iron shieldcooling

Inside double-door

FY2003 FY2004 FY2005 FY2006 FY2007 FY2008

Support for target and horns

Conceptual design

Basic prototype

Design Prototype Production Installation

Helium container Conceptual design

Basic prototype

Design Prototype Production Installation

Mockup

Remote maintenance

Conceptual design

Basic prototype

Design Prototype Production Installation

Cooling Conceptual design

Prototype Design Production Installation

Shield Conceptual design

Prototype Design Production Installation

Building Conceptual design

Design Construction

ScheduleBudget for TS(our hope)

Summary

•Conceptual design of Target Station finish soon.•Building•Shielding•Cooling•Support •Maintenance

•Realistic design, R&D work and prototyping will start.•Construction will start in 2006 and end in 2008

if budget is approved.

Backup

10-410-310-210-1100 101 102 103 104 10510-3

10-2

10-1

100

101

102

103

104

AL

Fe

After one year irradiation

Time (Hour)

Eff

ecti

ve

Do

se (

mS

v/h

)

Na-24

Na-22

Effect of Aluminum wall

Aluminum wall reduces surface dose by ~1/10 at maintenance.Cost vs Performance should be studied.

After one year irradiation

1day 100 days

Time after irradiation (hour)

~100mSv/h

Dos

e at

tar

get

area

(m

Sv/

h)

Aluminum

Iron

Secondary cooling water system

Third cooling water system

Primary cooling water system

Heat exchange

To 2nd machine building

Cooling system for Target/Horn

water line

Secondary

Disposal to buffer

tank for DV

Pumps

Filters for radioactivity

Degassing system

Water

Buffer tank

Underground machine pit

(TP+2.7m)

Service pit

(TP+2.7m)

Target area

(TP-1.7m)

1st horn10kw200 litter

Primary cooling system for horn

30litter/min.

in experiment

in maintenance

Very rough cost estimation

•Building: ~4.3M$(Underground) + ~0.8M$(Surface)•Crane: ~0.5M$•Concrete shield blocks: 1600m3~300$/m3 = ~0.5M$•Iron shield blocks: 4000ton(200~300)$/ton = 0.8~1.2M$•Helium container: 160ton~1000$/ton~2? = 0.3M$?•Aluminum wall: 120ton~3000$/ton~2? = 0.7M$?•Support system of horn: ~0.1M$?4 = ~0.4M$?•Air cooling & ventilating system: ?•Water cooling system: ?

•1M$ ~ 1108 Yen•Excluding horns and target

Service pit(230m3)Machine room(140m3)Keep out in experiment•In experiment:circulation•In maintenance:ventilation

Control of airBuilding (8300m3):•Ventilation through stack

Helium container:Keep out forever•Circulation of Helium

Stock room for radioactive partsKeep out forever•In experiment :circulation•In maintenance:ventilation

Area for rem

oved

shield

s

Area for entrance control

Operation room for maintenance

Area for spare horns

Storage for radioactive material

Traile

r

Underground machine room

33m

22m

Top view of target station

beam

Underground machine room

•ターゲット一次冷却水（ 0.01m3,28kBq/cc ）のポンプ＋タンク、熱交換器 (~30kW) 、二次冷却水のポンプ＋タンク

•ホーン一次冷却水（ 0.6m3,5kBq/cc ）のポンプ＋タンク、熱交換器 (~30kW) 、二次冷却水のポンプ＋タンク

•鉄シールド＋アルミヘリウム箱一次冷却水（数 m3?, 数 kBq/cc? ）のポンプ＋タンク、熱交換器 (~200kW)（二次系は FF 部と共通）

•ディケイボリューム一次冷却水（ 3m3, 数 kBq/cc ）のポンプ＋タンク、熱交換器 (~200kW)（二次系は FF 部と共通）

排水は地下機械室よりディケイボリュームを通って下流の DP タンクへ

放射化物保管庫

　　　地下機械室　

FF 部DV

空気・ヘリウムの放射化

場所Neutron fluence

(/p/cm2)

放射化(Bq/cc)

容量(m3)

トリチウム (Bq)

排気時間(h)

上屋 110-19 410-14 8000 0.3 1

サービスピット 510-12 210-6 230 5105 0.03

地下機械室 510-12 210-6 330 7105 0.04

放射化物保管庫 510-12 210-6 780 1.6106 0.1

鉄シールド外面 110-10 410-5 38 1.5106 0.005

鉄シールド中間 110-8 410-3 33 1.3108 0.004

鉄シールド内面 210-5 8 28 2.21011 5.6

TS ヘリウム 210-4 80? 135 1.11013? 270?

DV ヘリウム 510-5 20? 1600 3.11013? 800?

0.75MW20 日運転後（反応断面積 30mb ）排気基準： 5mBq/cc 以下

ヘリウムの断面積は 1.2mb ？（ 1/25 ？）

Neutrino target

Graphite rod•diameter:30mm, Length:900mm (80% interaction)•beam size: σr ~6mm

•fixed inside 1st horn•20kw heat load: cooled by water

Hayato’s talk tomorrow

1st Horn 2nd Horn3rd HornTarget

0.75MW beam

鉄シールドブロック

2mX1.5mX1m (23 トン）　 36 個＝ 810 トン

3mX1.5mX1m (34 トン）　 72 個＝ 2430 トン

2.2mX2.2mX1m (36 トン）　 18 個＝ 650 トン

合計３９００トン平成 18 年度製造、 19 年度据付

冷却面（水冷又は空冷、２５０ｋ W ）

水冷の場合、冷却管取付けIron shield