Heavy ion accelerator task (6) (leader: M.-H. Moscatello)
LMU München
BEAM ENERGIES AND LOSSES ALONG THE POST-ACCELERATOR, INPUT FOR SAFETY AND RADIOPROTECTION presented by
Alexander Bechtold
(sub- task "Normal Conducting Injector)
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
Task 6: "Heavy Ion Accelerator" LMU München
•
Experimental Requirements (N. Orr)
•
Superconducting RFQs (B. Bisoffi, A. Palmieri, A. Pisent, A.-M. Porcellato, P.A Posocco)
•
Normal conducting RFQs (A. Bechtold)
•
Linac (J.-L. Biarrotte, P. Bertrand)
•
RF-Chopper (G. Ledem, M. Di Giacomo)
•
Design suggestion of a dedicated β-beam linac* (A. Bechtold, H. Podlech) *actually not an issue of T6
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
Experimental Requirements (N. Orr) LMU München
•
Maximum Beam Energy (132Sn25+ reference beam) 150 MeV/u * ⇒ high-acceptance, high resolution fragment separator LINAC operation with/without stripping -> highly desirable for weakest beams – both modes of operation should be possible (??)
•
Minimum Beam Energy “design” minimum defined by RFQ ~ 0.5 - 0.7 MeV/u ⇒ dedicated “LE” accelerator for astrophysics etc
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
Experimental Requirements (N. Orr) LMU München
•
Energy Variability ~0.5 % at low-medium energies (0-20 MeV/u) ~1 MeV/u at high energies (>20 MeV/u)
•
Beam Energy Definition/Absolute Beam Energy ~ 0.1 % or better at low-medium energies (0-20 MeV/u) ~ 0.1 % at high energies (>20 MeV/u) if possible (??) ⇒ need beam energy analysis spectrometer(s) (at high energies fragment separator should fulfill this role) ⇒ fast and precise beam energy changes at LE (0-5 MeV/u)
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
Experimental Requirements (N. Orr) LMU München
•Beam Sharing - Many VLE and LE/near barrier expts (0-5MeV/u) require very extended periods of beamtime with same beam (astro’, heavy elements, etc).
⇒ Dedicated VLE, LE and HE accelerator(s) [~0-1, ~1-5 and ~5150 MeV/u] coupled to separate target-ion source systems.
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
Proposal of SRFQs for EURISOL post accelerator. (B. Bisoffi, A. Palmieri, A. Pisent, A.-M. Porcellato, P.A Posocco)
Task 6 – EURISOL DS
SRFQ buncher in out 2,35 168,8 Energy 0,56 40,18 0,0022 0,019 Beta 93 93 Voltage 148,5 Length 167 Ncell 1 2,6 m 0,5 0,288 a 0,5 0,5 R0 -90 -25 φs 25 Max.Sur. Field 0,51 Stored Energy
NC
SRFQ1 in out 423,4 100,77 0,0302 200 200 128,1 29 1,2 2,8 0,9 0,5 1 1 -40 -18 25,4 3,1
LMU München
SRFQ2 in out 672 159,93 0,038 290 290 83,3 13 2,8 2,8 0,8 0,8 1,6 1,6 -8 -8 23,7 4,2
keV/A MeV kV cm
cm cm deg MV/m J
SC
PIAVE A. Bechtold IAP Frankfurt
LNL
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
The need for small apertures at RFQ bunching -> NC-RFQ!
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
LMU München
[email protected]
The proposed PIAVE NC 4-vane CW RFQ (A. Palmieri, INFN) LMU München
Transmission Longitudinal RMS Emittance Transverse Normalized RMS Emittance (in/out)
99.97 0.28 0.2/0.2
% (tested on 100k, macroparticles) keV / u ns mmmrad
Voltage
43.3
kV (constant)
Duty Cycle
100
%
Initial Energy
2.35
keV / u
Final Energy
37.1
keV / u
Total Length
2
R0 (initial/final) Particle
3.4
m (0.53 ) mm
A / q = 8.5
Frequency
80
MHz
Maximum Surface Field
18
MV/m (1.8 Kilpatrick)
RF Power Consumptions
~ 10
kW
Minimum aperture a
2.5
mm
Maximum modulation m
1.6
Total Cell number
360
Focusing factor B (initial/final)
6.65
Bunch length (2 phi RMS)
0.6
ns
Energy Spread ∆W/W RMS
2.5
%
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
THE MAFF IH-RFQ (A. Bechtold) LMU München
length
3m
frequency
104 MHz
m/q
≤ 6.3
Voltage
≤ 60 kV (9.5 kV *m/q)
Q-value
5750
Shunt impedance
168 kΩ Ω*m
Win
2.5 keV/u
Wout
300 keV/u
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
4-rod-RFQ at CW (A. Bechtold) LMU München
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
Proposal for a NC-buncher RFQ for EURISOL post accelerator (A. Bechtold)
LMU München
length l
245 cm
frequency f0
88 MHz
mass to charge ratio m/q
≤9.52
input energy Win
2.35 keV/u
output energy Wout
167 keV/u
aperture a
0.43 cm
electrode voltage Vel
60 kV
RF-power consumption PRF
82 kW
duty cycle
100%
input emittance rms normalized
0.1 mm mrad
transmission T (0 mA/7.5 mA)
100%
97.9%
transval emittance growth ∆εt (0 mA/7.5 mA)
4%
8.5%
energy spread ∆W (0 mA/7.5 mA)
1.5%
2.5%
phase width ∆ϕ (0 mA/7.5 mA)
±17°
±22.8°
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
A normal conducting RFQ tandem as an injector for superconducting QWRs (A. Bechtold)
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
LMU München
[email protected]
A normal conducting RFQ tandem as an injector for superconducting QWRs (A. Bechtold)
LMU München
NC-RFQ1
NC-RFQ2
l
387 cm
395 cm
f0
88 MHz
88 MHz
m/q
≤9.52
≤9.52
Win
2.35 keV/u
260 keV/u
Wout
260 keV/u
460 keV/u
a
0.43 cm
0.43 cm
Vel
60 kV
60 kV
PRF
131 kW
131 kW
duty cycle
100%
100%
εrms,n input
0.1 mm mrad
0.104 mm mrad
T (0 mA/7.5 mA)
100%
97.9%
99.8%
94.4%
∆εt (0 mA/7.5 mA)
4%
9%
0%
1.5%
∆W (0 mA/7.5 mA)
1.2%
2.5%
1%
2%
∆ϕ (0 mA/7.5 mA)
±17°
±23°
±15°
±18°
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
General linac specifications (J.-L.-Biarrotte) LMU München
1.
3 separate post-accelerators: VLE ( 585.4 keV/u for all ions @ 88.05 MHz (β = 0.035) -> Emittances (trans. & long.) = 0.1 pi.mm.mrad RMS NORM
•
Nominal operation for A/Q between 4 and 8
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
5 MeV/A linac design (J.-L.-Biarrotte) LMU München
A/Q=8
Section 1
Section 2
TOTAL
Cavity Freq.
88.05 MHz
88.05 MHz
-
Cavity β
0.05
0.085
-
# cav./ cryo
1 QWR
2 QWR
-
# cavities
9 cav
14 cav
23 cav
Final energy (MeV/u)
One short linac, with no intermediate-energy exit, optimized for A/Q = 8
10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0
Max output energy = f (A/Q)
2
4
6
8
10
12
Mass over charge
Length Output energy range
11.2 m
12.6 m
23.8 m
-
0.95 – 5.0 MeV/u
0.95 – 5.0 MeV/u
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
150 MeV/A linac design (J.-L.-Biarrotte) LMU München
One linac, with 2 intermediate-energy exits: 150 MeV/A max. output energy tuned for 132 Sn 25+ (A/Q=5.28) 132 Sn 25+
Section 1
Section 2
Section 3
Section 4
TOTAL
Cavity Freq.
88.05 MHz
88.05 MHz
176.1 MHz
264.15 MHz
-
Cavity β
0.065
0.14
0.27
0.385
-
# cav./ cryo
1 QWR
3 QWR
8 HWR
14 SPOKE
-
# cavities
15 cav
27 cav
80 cav
154 cav
276 cav
Length
17.9 m
26.1 m
59.0 m
103.8 m
206.8 m
-
2.1 – 19.9 MeV/A
9.3 – 62.5 MeV/A
20.0 – 150.0 MeV/A
2.1 – 150.0 MeV/A
Ouput energy range
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
A DEDICATED β-BEAM LINAC CONCEPT COMPRISING CH-DTLs (H. Podlech)
LMU München
IH structure
The total length would be about 110 m.
CH structure
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
FOR EXPAMLE: 70 MeV, 70 mA NC-CH H+-DTL for GSI LMU München
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
A DEDICATED β-BEAM RFQ CONCEPT (A. Bechtold) LMU München
4-rod CW RFQ
length l
275 cm
frequency f0
176 MHz
mass to charge ratio m/q
≤3
input energy Win
8 keV/u
output energy Wout
1 MeV/u
electrode voltage Vel
95 kV
input emittance total
50 mm mrad
transmission T (50 mA)
97%
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
Losses at preliminary designs LMU München
150 MeV/u for 132Sn25+
585.4 keV/u - 673 keV/u
Chopper
Losses < 10-5
NC: Losses ≤ 2*10-3 SC: Losses ≈ 0
Joint collaboration meeting with EURISOL-DS Task5 12.-13..10.2006, Munich: Task VI "Heavy Ion Accelerator"
[email protected]
