ELECTROSTATIC SEPARATORS AT THE J-PARC HADRON HALL

Michifumi Minakawa , Masaharu Ieiri, Keizo Agari, Yohji Katoh, Erina Hirose, Ryotaro Muto, Megumi Naruki,

Yoshinori Sato, Yoshihisa Shirakabe, Yoshihiro Suzuki, Shin’ya Sawada, Hitoshi Takahashi, Kazuhiro Tanaka,

Akihisa Toyoda, Yutaka Yamanoi, and Hiroaki Watanabe

IPNS, KEK, Oho 1-1, Tsukuba, Ibaraki 305-0801, Japan

Abstract Electrostatic (ES) separators to select and deliver below 2GeV/c secondary beam are launched out at the secondary

beam line at the high intensity proton accelerator facility (J-PARC). The ES separator will generate a 75kV/cm electrostatic field between parallel electrodes along the beam direction. It is designed so as to be radiation-proof and to lower spark rate comparing with the present separators. A checkout by measuring K-/π- ratio of the line has been performed.

J-PARC

1. K

(ES(Electrostatic) )

[1] ES

ES

• m30cm

10 15 cmSUS

+300kV -300kV

• 1 10-4 Pa He 1 10-9

Pa m3 sec. •

ES

•

Ne-He1 10-2 Pa

•

2. J-PARC

K1.8 K1.1BR KKL

1 .

K1.8 2GeV/c6m ES

K

K[2] ES

ESS2

ESS1

K1.1BR area

KL area

K1.8

KL

T1 target beam

dump

30GeV protons

K1.8BR area K1.8 area

K1.1BR

ESS

____________________________________________ #minakawa@post.kek.jp

Proceedings of the 8th Annual Meeting of Particle Accelerator Society of Japan (August 1-3, 2011, Tsukuba, Japan)

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(CM1-CM4)ES

K1.8ES (D3)

K1.8BR

2 IF

MS1,MS2 1

K1.1BR 1.1GeV/c2m ES

K1.1ES K1.8

K0

S

KK1.8

K1.1BR ES

[3]

3.

ES

J-PARC

[4]

3.1

EPT O-O-

( )

FRPFiber Reinforced Plastics

FRP

FRP

400kV

3

3.2

R11

4

Proceedings of the 8th Annual Meeting of Particle Accelerator Society of Japan (August 1-3, 2011, Tsukuba, Japan)

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R30

0.05 0.2

3.3

SUS

t=10R1=8 R2=2 ES

25% (5(a) (b))

(a) (b) J-PARC

5 ANSYS

6 SUS SUS

SUS 50mmSUS 100mm 0.35mm

Proceedings of the 8th Annual Meeting of Particle Accelerator Society of Japan (August 1-3, 2011, Tsukuba, Japan)

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4. ES ES 3m

6m

100mm

0.5mm

5. ES

6mES 3m

5mm

6m5.5m

7(pole) (pivot)

8 K1.8

6. K1.8BR K1.8 K1.1BR ES

K1.8BR 0.75GeV/c ES

200kV

- K-

K1.8 1.8GeV/c ES

200kV 4K

KK

ES K

K1.1BR0.8GeV/c K+

K K.14

pole

pivot

pole

pole

Proceedings of the 8th Annual Meeting of Particle Accelerator Society of Japan (August 1-3, 2011, Tsukuba, Japan)

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9 K1.8BR 0.75GeV/c

ES 200kV

- K-

10 K1.8 1.8GeV/c ES

200kV 4

K

K

ES

(a) ES (b)

K

11 K1.1BR 0.8GeV/c K+

K K .14

K1.8BR

K1.8

ESK1.1BR

K

ES

K1.8BR K1.8 K1.1BR

J-PARC E17 E19E06

(B) (21340071)

[1] A. Yamamoto et al., Nucl. Instr. and Meth.

148(1978)203-207; A. Yamamoto et al., Nucl. Instr. and Meth. 203(1982)35-43; S. Kurokawa et al., Nucl. Instr. and Meth. 212(1983)91-100; M. Takasaki et al., Nucl. Instr. and Meth. A242(1986)201-207.

[2] P. H. Pile et al., Nucl. Instr. and Meth. A321(1992)48-5.

[3] K. H. Tanaka et al., Nucl. Instr. and Meth. A363(1995)114-119.

[4] M. Ieiri et al., Nucl. Instr. and Meth. B266 (2008) 4205-4208.; M. Ieiri et al., Int’l Particle Accelerator Conf. (2010) THPEC045.

(a) ESS1 off ESS2 off ʻKʼtrigger

(b) ESS1 on ESS2 on ʻKʼtrigger

Proceedings of the 8th Annual Meeting of Particle Accelerator Society of Japan (August 1-3, 2011, Tsukuba, Japan)

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