TEST OF A 3 GHz HIGH-GRADIENT ACCELERATING CAVITY
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Transcript of TEST OF A 3 GHz HIGH-GRADIENT ACCELERATING CAVITY
TEST OF A 3 GHz HIGH-GRADIENT ACCELERATING CAVITY
U. Amaldi, R. Bonomi, A Degiovanni, M. Garlasché, A. Garonna, I. Mondino, P. Pearce, P.L. Riboni, V. Rizzoglio and S. Verdù Andrès
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General Concept of a CyclinacGeneral Concept of a Cyclinac
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The energy can be varied in 2-3 ms in the full range by changing the power pulses sent to the 16-22 accelerating modules (forming 8-11 RF Units)
computer controlled
source
(synchro)cyclotron
gantry
chopped beam at 100-400 Hz
linac Units
fast-cycling beam for tumour multi-painting
RF generators
beams used for other medical
purposes
IBA
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source
General Concept of a CyclinacGeneral Concept of a Cyclinac
LINAC
CyclinacsCyclinacs
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1993: first Cyclinac proposal
30 MeV cyclotron
CTF3 Committee - UA - 24.3.11
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1993: first Cyclinac proposal
30 MeV cyclotron CyclinacsCyclinacs
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2003: test of LIBO-62 MeV (M. Weiss - TERA-CERN-INFN)
1993: first Cyclinac proposal
30 MeV cyclotron CyclinacsCyclinacs
CTF3 Committee - UA - 24.3.11
2003: test of LIBO-62 MeV (M. Weiss - TERA-CERN-INFN)
1993: first Cyclinac proposal
30 MeV cyclotron
2007: first CABOTO design
CyclinacsCyclinacs
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2003: test of LIBO-62 MeV (M. Weiss - TERA-CERN-INFN)
1993: first Cyclinac proposal
30 MeV cyclotron
2007: first CABOTO design
2008: Pediatric IDRA for Biella
CyclinacsCyclinacs
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2003: test of LIBO-62 MeV (M. Weiss - TERA-CERN-INFN)
1993: first Cyclinac proposal
30 MeV cyclotron
2007: first CABOTO design
2010: First Unit of LIGHT ADAM=Application of Detectors
and Accelerators to Medicine
2008: Pediatric IDRA for Biella
CyclinacsCyclinacs
10
2003: test of LIBO-62 MeV (M. Weiss - TERA-CERN-INFN)
1993: first Cyclinac proposal
30 MeV cyclotron
2007: first CABOTO design
2009: First Unit of LIGHT ADAM=Application of Detectors
and Accelerators to Medicine
2008: Pediatric IDRA for Biella
CyclinacsCyclinacs
2010TULIP +
CABOTO
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400MeV/u
CABOTO – C =
CArbon BOoster for Therapy in Oncology
150MeV/u
CABOTO-C components
Source EBIS - SC
Cyclotron K 600 - SC210 tons
Linac CCL @ 5.7 GHz14 modules
RF power system
14 Klystrons (Ppeak = 12 MW)
150-400 MeV/u
The last design of a cyclinac for carbon ions: The last design of a cyclinac for carbon ions: CABOTO-CCABOTO-C
Dimensional comparison among carbon ion accelerators
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TULIP = TUrning LInac for Proton therapy35 MeV cyclotron
3 or 5.7 GHz linac
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Proton trajectory
15-20 MV/m
14
62 MeV
74 MeV
4 MW at 3 GHz
LIBO
LIBO and LIGHT at 3 GHz: gradient E ≤ 20 MV/m
Surface field Es ≤ 90 MV/m(Kilpatrick ≤ 2)
SW Cell Coupled Linac for SW Cell Coupled Linac for ββ = 0.25-0.60= 0.25-0.60
CTF3 Committee - UA - 24.3.11
Proton trajectory
15-20 MV/m
15
62 MeV
74 MeV
4 MW at 3 GHz
LIBO
LIBO and LIGHT at 3 GHz: gradient E ≤ 20 MV/m
Surface field Es ≤ 90 MV/m(Kilpatrick ≤ 2)
SW Cell Coupled Linac for SW Cell Coupled Linac for ββ = 0.25-0.60= 0.25-0.60
For CABOTO and TULIP:E ≤ 35-40 MV/m
At 3 GHz or higher
CTF3 Committee - UA - 24.3.11
Proton trajectory
15-20 MV/m
16
62 MeV
74 MeV
4 MW at 3 GHz
LIBO
LIBO and LIGHT at 3 GHz: gradient E ≤ 20 MV/m
Surface field Es ≤ 90 MV/m(Kilpatrick ≤ 2)
SW Cell Coupled Linac for SW Cell Coupled Linac for ββ = 0.25-0.60= 0.25-0.60
For CABOTO and TULIP:E ≤ 35-40 MV/m
At 3 GHz or higher
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Es / E ≤ 4.5 - 5
Problem: ‘the Nose’
Proton trajectory
15-20 MV/m
17
62 MeV
74 MeV
4 MW at 3 GHz
LIBO
LIBO and LIGHT at 3 GHz: gradient E ≤ 20 MV/m
Surface field Es ≤ 90 MV/m(Kilpatrick ≤ 2)
SW Cell Coupled Linac for SW Cell Coupled Linac for ββ = 0.25-0.60= 0.25-0.60
For CABOTO and TULIP:E ≤ 35-40 MV/m
At 3 GHz or higherEs / E ≤ 4.5 - 5
‘Nose’
As far as Es is concerned:
TERA’s 40 MV/mare equivalent to CLIC’s 100 MV/m
Problem: ‘the Nose’
Proton trajectory
15-20 MV/m
18
62 MeV
74 MeV
4 MW at 3 GHz
LIBO
LIBO and LIGHT at 3 GHz: gradient E ≤ 20 MV/m
Surface field Es ≤ 90 MV/m(Kilpatrick ≤ 2)
SW Cell Coupled Linac for SW Cell Coupled Linac for ββ = 0.25-0.60= 0.25-0.60
For CABOTO and TULIP:E ≤ 35-40 MV/m
At 3 GHz or higherEs / E ≤ 4.5 - 5
BDR for TERA:Linac is 15 m long and a treatment is (20x100 Hz x120s) pulses
BDR ≤ 3 10-7 CTF3 Committee - UA - 24.3.11Problem: ‘the Nose’
Proton trajectory
15-20 MV/m
19
62 MeV
74 MeV
4 MW at 3 GHz
LIBO
LIBO and LIGHT at 3 GHz: gradient E ≤ 20 MV/m
Surface field Es ≤ 90 MV/m(Kilpatrick ≤ 2)
SW Cell Coupled Linac for SW Cell Coupled Linac for ββ = 0.25-0.60= 0.25-0.60
For CABOTO and TULIP:E ≤ 35-40 MV/m
At 3 GHz or higherEs / E ≤ 4.5 - 5
TERA is facing the same challenges as CLIC BUT
cannot go to freguencies larger than 6 GHz:
tranverse acceptance,distributed sources
CTF3 Committee - UA - 24.3.11Problem: ‘the Nose’
Since 2009 TERA has started an high gradient Since 2009 TERA has started an high gradient test Programtest Program
Prototype test structures:3 GHz single-cell cavity5.7 GHz single-cell cavitymulti-cell structure
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3 GHz Test Cavity general layout3 GHz Test Cavity general layout• Single accelerating cell
• H-coupled to WR284 waveguide
• Cooling system (two plates, in-out pipes)
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Preliminary high power testPreliminary high power test
High Power Test (@CTF3 – Feb 2010)
Preliminary results compared with literature data[A. Grudiev et al, Phys. Rev. ST Accel. Beam 12 (2009)]
Indirect measurments of field through Faraday Cup
BD event
S. Verdú Andrés et al. (2010) LINAC10 Proceedings
3 µs1 µs
Low Power Measurments (Jan 2010)
short position
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High power test: first results after few nights and no conditioning
x = 30 (other expriments)x= 6 TERA @ 3 GHz
acceptable range
150 – 170 MV/m
Microscopy surface InspectionMicroscopy surface Inspection
Microscope’s inside view on nose region: several craters and sparse activity can be observed.
Difficulties in reconstructing the actual position of the craters.
Final conclusion will come after cutting and opening the cavity.
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To complete the measurementTo complete the measurement
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we request 4 weeks
for mounting, conditioning and testing
this cavity
The pieces of the 5.7 GHz test cavity are inhouse The pieces of the 5.7 GHz test cavity are inhouse
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Low power tuning in 10 daysTo be tested after the 3 Ghz cavity in Frascati (L. Picardi)
(with ADAM’s magnetron)
Prototype # 1 & 2 3 tendering
Material C10100 Copper
Dimensional tolerance band 10 μm 5 μm
Surface roughness (Ra) 0.4 μm 0.025 μm