s.watanabe, y.ohshiro, s.yamaka, s.kubono (cns, univ. of tokyo) t.nakagawa, t.watanabe, t.koseki,...
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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