S.Watanabe, Y.Ohshiro, S.Yamaka, S.Kubono (CNS, Univ. of Tokyo) T.Nakagawa, T.Watanabe, T.Koseki,...
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Transcript of S.Watanabe, Y.Ohshiro, S.Yamaka, S.Kubono (CNS, Univ. of Tokyo) T.Nakagawa, T.Watanabe, T.Koseki,...
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