S.Watanabe, Y.Ohshiro, S.Yamaka, S.Kubono (CNS, Univ. of Tokyo)

T.Nakagawa, T.Watanabe, T.Koseki, Y.Chiba, A.Goto, S.Kohara, M.Kase (RIKEN)

M.Fukuda (JAERI-Takasaki), T.Hattori (TIT), M.Nishiura (NIFS) 　

K.Noda, S.Hojo (NIRS), M.Watanabe (JAERI-Tokai), M.Oyaizu, H.Miyatake (KEK) 　

Dec/07/2005 CNS-PAC

Upgrade of K70 AVF Cyclotron and Accelerator Development at CNS

Dec/07/2005

１０１０ GHGHｚｚECRECR

Upgrading of K70 AVF Cyclotron

HyperECR:Increasing beam intensity & Development of New element acceleration

Dec/07/2005 CNS-PAC

Researches using low energy RI beam will be extended by increasing primary beam intensities, expanding the acceleration energy range and improving the beam quality.

K70 AVF: Expanding Acceleration energyand improving beamquality

Background

Upgrading of K70 AVF Cyclotron－　 Expanding Acceleration Energy 　ー

Plans & Result

●Change of Deflector （’ 03 )●Upgrade Main Coil PS（’ 04)

・ＩＭＣ＝１１４４．３１Ａ→ 　 Power rating up to ＋４％

・ Max Current １１００Ａ→１２００Ａ

●Upgrade Trim Coils（’ 05)　・ Make isochrones field at K78 by Ｃ５、

Ｃ６　・Ｃ５ PS: Up to ２００Ａ ( １３２Ａ

required)　・Ｃ 6PS: Up to ２ 5 ０Ａ (172 Ａ

require)●RF Acceleration system （ in progress)　　・ Nominal Ｄｅｅ Vol.= ５０ｋＶ＠１

６ＭＨｚ　　・ > ５６ｋＶ : Pre. Amp. （８００

Ｗ） is required　　・５０ｋＶ at Dee is OK for F1　　・ Improvement of FT system is

required for Δ Ｅ / Ｅ＝ 0.01 ％ (goal)●Modify the central region 　ｈ＝ 1,2,3

（’ 06) 　●Modify the Magnetic channel （’ 07)

ex ； 9MeV/u 15N5+ 　 10pA(expected)B ： 1.298 (T), Rf ： 18.447(MHz) 、ｈ＝ 2 　（ｈ： harmonic number ＝ number of bunched beam ）

Acceleration Energy 　Ｋ７０→Ｋ７８

原研高崎：福田光宏、理研：後藤、小原、長瀬、加瀬氏との共同研究 Dec/07/2005 CNS-PAC

Beam from ECR

Acc. gap

Magnet

Inflector

DeeDeflector

Grazer lensesBeam

focusing lenses

Upgrading of K70 AVF CyclotronCentral region

●Central region 　ｈ＝１，２，３（’ 06) 　・ Inflector electrode for each 　harmonic

→ 　ｈ＝１、２、３・ Dee tips → Wider acceptance for the mode of all harmonics・ New RF shield for the mode of all harmonics

●Inflector electrodes changer　　・ Automatic insertion and quick

exchange

RF shield

Dee tipsInflector electrode

40 MeV ProtonB ：　 1.29 (T), RF ： 18.9 (MHz) 、ｈ＝１（ｈ： harmonic number)

Expansion of acceleration energy

h=3 allows q/A=5/1

Upgrade Main Coil PS (’04)

Dec/07/2005 CNS-PAC

Old Trans

New Trans

installation

-continued-

Upgrading of K70 AVF Cyclotron －　 Improvement of RF System 　ー

Dec/07/2005 CNS-PAC

Discharge occurs mainly at the lower ceramics insulator.

Discharge occurs at variable coupling condenser (VCC)

Vf1

Vf3

Vf1 +Vf3

12

Upgrading of K70 AVF Cyclotron －　 Improvement of RF System (continued) －

Teflon covers suppress emission of electron from the high potential

Attained ５０ｋＶ＠１６．３ＭＨｚ /FT

Result

Dec/07/2005 CNS-PAC

Corona ring of VCC Leaks emission of electron

1

2

 

Ion Species

Accel. Energy[Me/u]

Ion source 　 　current [eA]

[%] Extracted beam 　 　current [eA]

H+ 9.9 56 14 7.8

12C4+ 7.0 28 19 5.3

13C4+ 5.5 15 25 3.8

14N5+ 7.0 33 13 4.3

14N6+ 6.4 6 29 1.7

20Ne 6.3 12 25 3.0

7Li2+ 3.1 5 6 0.3*

7Li3+ 8.7 13 5 0.7**

40Ar11+ 95 40 11 4.4

beam list @Vext=6~11KV 　

Hyper ECR－ Increasing beam intensity and number of elements －

7Li3+7Li2+

Mass separation of 14N5+ and 7Li3+

1st ,Tune AVF to 14N5+

2nd ,Tune AVF to 7Li3+ by B adjust Dec/07/2005 CNS-PAC

: Transmission 　 efficiency *LiF rod / Nishimura Gr, March ‘05**Li filled crucible / Yamaguchi Gr, Sept ’05

　↑ LiF rod(8X105L)

Crucible→・ volume ： 5 (cc)・ Li weight ： 1.7 (g)

　　　　　　↑Photo of plasma chamber

① 　７ Li2+ → LiF rod 　（ LiF ： m.p=1143K ）② 　７ Li ３＋→ Crucible 　（ Fill piecemeal of ７ Li ）RF power conditions　７ Li ２＋：１５０　 W　７ Li ３＋：３００　 W　※３００ W→LiF melt down　　　→ use of crucible

７ Li2+, ７ Li３＋

Dec/07/2005 CNS-PAC

Ｌｉ source

①②

Hyper ECR -continued-

Low energy bunched ion beam facility at CNS Faraday cup

Cluster-ISRF-Buncher

HiECR-IS

Accelerator Development

needle monitor

Volume Ion Source VIS)

Dec/07/2005 CNS-PAC

Charge Breeding type ECR (CBECR)

q=1+ Ion source ＨｉＥＣＲ

Injection system

Cross-section of CBECR

－ Charge Breeding type ECR ion source (CBECR)－

Accelerator Development

Simulation of q=1+ Ion beam, Ein=10KV

Deceleration voltage. 0V, 10kV, 9.995kV① ② ③

①

②

③

• Simulation of injection beam

•　 Design the beam injection system

•　 Purchase the mechanical parts

Advanced

•Upgrade of HiECR is in progress

q=1+ Ion (Ar1+)

q=n+ Ion (Ar11+)

q=1+ Ion source; Gas or Metal ion

Dec/07/2005 CNS-PAC

Ein=10KV Eext=10KVEdec=9.995kV

q=n+ Ion

q=1+IS Einzel

Accelerator Development -Volume type ion source (VIS)-

Type ：　 Kaufman type ion source

Volume ：１０５ｍｍ D 、１１０ｍｍ L

Weight ：１ｋｇ

Plasma confinement ：　 Cusp field （ Ned １Ｔ、 6 poles ）

Ion ：　 Ar1+, H+, H- (achieved)

Vext. ：　６ＫＶ max

I beam ：　１．５ｍＡ

CBECR aims at effective extraction of high charge Ar ions from the injected Ar1+. We have developed a volume type ion source for production of Ar1+.

核融合研　西浦正樹氏との共同研究 Dec/07/2005 CNS-PAC

Test bench

Spec

Accelerator Development-Broad band RF cavity as a Beam buncher-

We have designed and constructed a broad-band RF cavity as a buncher of heavy ion beams from an ion source. The cores employed are Finemet cut cores for low-Q cavity. The operating frequencies are between 18 and 40 MHz. The performance of the cavity has been tested at the beam line of the CNS-HiECR ion source.

Ar8+beam/18MHz

O5+beam/30MHz

H+beam/45MHz

理研：小関、原研東海：渡辺、放医研：野田、北條氏との共同研究

Dec/07/2005 CNS-PAC

RF cavity

Reflectron type mass analyzer (MA)　（m/Δm~ 2000） is required

Accelerator Development ‐ Cluster Ion Source/ High resolution TOF　‐

Design of Reflectron was completed with the aid of simulation code SIMION

Tuning of MA is in progress

理研：　中川孝秀氏との共同研究 Dec/07/2005 CNS-PAC

Accelerator Development ‐ Cluster Ion Source/ Sputtering type ionizer‐

•Ionizer: Magnetron type sputter

•Metal target: Li~Cu

•Target support: Movable holder

•Plasma exciter: RF discharge

•Support gas: 　 He or Ar

•Gas pressure: １ mTor ｒ～ 100mTorr

•Plasma confinement: Magnetic field+Rf electric field(13.56MHz)

•Plasma potential: 　６００ eV

•Sputtering efficiency 　０．１～２．３•Ion production rate: 　１０１２／ｃｍ３

The cluster ion source includes long-life ionizer with large intensity as a internal primary ion source. Sputtering type ionizer is under trial production.　

理研：　中川孝秀氏との共同研究 Dec/07/2005 CNS-PAC

目標感度

１ナノアンペア

Ion Beam Modification (IBM) of Current Sensor for the HTS-SQUID Monitor

Ar2+ bombardment: 20eA/cm2 　 @HiECR

Accelerator Development ‐ High Temperature Super conducting (HTS)-SQUID Monitor‐

Target=Bi2223

Beam Test at RRC

理研：渡辺環氏との共同研究 Dec/07/2005 CNS-PAC

Current Sensor (Bi2223 / MgO)

HTS-SQUID

After IBM with100m beam slit

Study of HTS twin coils has been done with IBM.

100

m

•Main Coil & Trim PS’s of AVF were upgraded for expansion of beam energy from K=70 to K=78. 　

•AVF RF System with FT attained 50kV at 16.3MHz.

•７ Li2+ was firstly extracted from HyperECR with LiF rod.

•７ Li3 ＋ was extracted from HyperECR with Li-filled crucible. •Low energy bunched ion beam facility at CNS was constructed. •Conversion of HiECR into CBECR is in progress.•Ar1+, H+, and H- were extracted from Volume type Ion Source. •Sputtering type Ionizer for Cluster Ion Source is under trial production.•Ion Beam Modification of Bi2223 has been done.

Dec/07/2005 CNS-PAC

Summary