Status of KEK 150MeV FFAG
M. Aiba (KEK)
For KEK FFAG Gr.
FFAG’05, 5 to 9 Dec., KURRI
Contents
Purpose of KEK 150MeV FFAG
Machine Parameters
Hardware improvements
Beam extraction and 100Hz operation
Status of accelerator performance
Summary
Purpose of150MeV FFAG
To be a prototype FFAG for various applicationsBeam extraction from FFAG for the first time
Rapid cycling
Test experiments for applications using extracted beam
Machine parameters
Lattice Triplet (DFD)Number of sector 12
k-value 7.6Energy (MeV) 12→ 150 (10→ 125)
Average radius(m) 4.47→ 5.20Betatron tune Hor.: 3.69~3.80
Ver.: 1.14~1.30
Maximum field (T) F: 1.63(on orbit) D: 0.78
Ion source of injector cyclotronHardware improvement (1)
Ion source: DC operation Pulsed operation
Cyclotron RF
Ion source
DC operation
Pulsed operation
Cyclotron RF
Ion source
Beam from cyclotron~200sec
~10secReduce unavailable beam (injection period of FFAG is few sec)Increase peak current 3~4times
Beam from cyclotron
RF systemHardware improvement (2)
Enhancement of RF system:
RF voltage: ~5kVpp ~12kVpp
Anode PS 55kW max. 300kW max.Vacuume tubeof main amp. 4CW25000A 4CW150000E
Drive mechanism for insertionsHardware improvement (3)
Attach drive mechanism toinjection septuminjection bumpsextraction kickerextraction septum
Extraction Septum
Position and angle can be changed while keeping vacuum.
Beam extraction
Fast extraction with kicker and septum
Realize 100% extraction efficiency
Top and side drawings of the septum magnet
Beam extraction experiment(1)Beam separation with kicker
0
0.05
0.1
0.15
0.2
0.25
0.3
5025 5030 5035 5040 5045 5050
Position [mm]
Sign
al [-
]
051026- 03t.wfm
O
Circulating beamSeparated beamwith kicker
0 30 60 90 120 150 180 210 240
- 40
- 30
- 20
- 10
0
10
20
30
40Kicker: main- 460Gauss, sub- 0Gauss
Del
ta_r
(m
m)
Theta (deg.)
Displacement of beam orbit by kicker (calculation)
Kicker
SeptumObservation
5mm*Septum field is not included in this calculation.
Beam extraction experiment(2)Experiment set up
Status of accelerator performance
First goal of accelerator developmentBeam energy: 100MeV
Rapid cycling: 100Hz
Beam current: 1nA
Status, Dec. 2005 Beam energy of100MeV has been achieved. 100Hz operation was successful. Beam current is more than 0.2nA@20Hz operation.
Basic accelerator R&D studies (design, construction, beam injection, acceleration and extraction) has been completed.
Summary
Many improvements since FFAG’04, KEK
Basic accelerator R&D studies has been completed.
First goal will be achieved soon.
Near future plan
Test experiments using the extracted beam
For medical application,
For ADS.