ebis injector linac optics i
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D. Raparia 2005/01/27-28EBIS Review
EBIS Injector Linac Optics ID.Raparia
EBIS Review 2005/01/27-28
•LEBT•RFQ•MEBT•LINAC
D. Raparia 2005/01/27-28EBIS Review
AcknowledgementsContributors:J. Alessi, E. Beebe, S. Pikin, A. Kponou, J. Ritter, C. Gardner, S. Y. Zhang, T. Roser
B. Schlitt, U. Ratzinger
D. Raparia 2005/01/27-28EBIS Review
Requirements• EBIS based linac should provide all the ions
species which presently Tandem provides
* Out of EBIS Linac scope
Z A Q Q/m Vext I(all ch states)
p* 1 1 1 1.00 17.0 10He3* 2 3 2 0.67 25.5 10
D 1 2 1 0.50 34.0 6C 6 12 6 0.50 34.0 10O 8 16 8 0.50 34.0 10Si 14 28 12 0.43 39.7 10Fe 26 56 16 0.29 59.5 10
Au 79 197 32 0.16 104.7 10
D. Raparia 2005/01/27-28EBIS Review
4 m 4.4 m
RFQ: 17 - 300 keV/u; 100 MHz
IH Linac: 0.3 - 2.0 MeV/u; 100 MHz
Proposed Linac –Based RHIC Preinjector
LEBTMEBTHEBT
Ion U - D
Charge 38 – 1 (q/m =.16-0.5)
Current 1.5 emA (for 1 turn inj)
Pulse Length
Rep. Rate
Duty Factor
10 s
5 Hz
0.0005 %
Emittance 0.7 mm rad (nor, 90%)
Energy Spread
1.8 keV/amu
D. Raparia 2005/01/27-28EBIS Review
Schematic of Ion Injection and Extraction from the RHIC EBIS (LEBT)
LEVA
HCIS
TOF
RFQEBIS
Cu +
Au 2+
d+
Au 2+ Cu +
Au 32+, Cu 11+ Au 32+,Cu 11+
d + SOURCE
d +
D. Raparia 2003/3/10-11MAC Review
LEBT Requirements-Inject into EBIS-Extract from EBIS-Acceleration-Diagnostics: Emittance Monitor, Current Monitor(2), TOF-Matching into RFQ Twiss parameters at beginning and end of the LEBT for Au+32
E = 17 keV/u=0.006017=1.000018
E = 5 keV/u=0.0033=1.000005
Parameters Beginning of LEBT (5 keV/u)
Middle of LEBT17keV/u
End of LEBT
Units
x -5.3 2.02 1.057
x 0.800 6.04 0.064 mm/mrad
x (4 rms, unnorm) 152 85 85 mm mrad
y -5.3 2.02 1.057
y 0.80 6.04 0.064 mm/mrad
y(4 rms, unnorm) 152 85 85 mm mrad
D. Raparia 2003/3/10-11MAC Review
Charge State DistributionComputer calculation of successive ionization of Au with a 20keV electron beam:
D. Raparia 2003/3/10-11MAC Review
Space Charge in LEBT
Envelope equation
0
4''
3
220
R
K
RRkR rms
Gen. Perv. (K)= QI/(2 0 m c3 33)
Debye Length(D) = 2 2rms/K
Current 10 mA, R=20 mm
Measurement for 1.7 mA Au+25 (n,rms) =0.1 mm mrad @ 20keV Simulated(n,rms) =0.125 mm mrad
Energy = 17 keV/u=0.006017=1.000018R= 20 mm
Z A Q Q/m vext EPS*(un) Perv(gen) ET SCT Ratio Debye Len ImaxP 1 1 1 1.00 17.0 80 0.00836 0.0019 0.4181 221.7589 0.000309 0.005
He3 2 3 2 0.67 25.5 80 0.00557 0.0019 0.2787 147.8393 0.000379 0.007D** 1 2 1 0.50 34.0 80 0.00251 0.0019 0.1254 66.52768 0.000565 0.010Si 14 28 12 0.43 39.7 80 0.00358 0.0019 0.1792 95.03955 0.000472 0.012Au 79 197 32 0.16 104.7 80 0.001358 0.0019 0.0679 36.02176 0.000767 0.030
*EPS(n, rms)=0.125 mm mrad ** I =6 mA
D. Raparia 2003/3/10-11MAC Review
LEBT Energy •Distance needed between two lenses for external ion injection (L) ~ 0.8 m.• Beam radius (R) ~ 2.0 cm, Lenses (solenoid) aperture radius 5 cm•Maximum beam current for SC dominated drift (L), maximum beam radius (R) and initial slop R’
0=-0.92 given by
Imax(A)=1.166*(mc2/30*q)*3 3 (R/L)2
Imax (mA)
E=8.5 keV/u E=17 keV/u
D 3.0 10.0
Au+32 10.0 30.0
L
2R
R’0=-0.92
D. Raparia 2003/3/10-11MAC Review
Investigated possible layouts for LEBT
Magnetic: Lower aberrations, need higher filed, separates charge estate
Electrostatic: Chromatic aberrations, screen reduce aberrations but also reduces intensity.
D. Raparia 2003/3/10-11MAC Review
Starting Conditions for LEBT
EBIS simulation by code TRAK (Kponou) generate input parameters for ion extraction/ acceleration for LEBT
E (keV)
(m)
(rms, norm)
mm mrad
Au+32 (10 mA) 970 -5.3 0.8 0.125
3He+2 (10 mA) 15 -3.6 0.6 0.123
E = 5 keV/u=0.0033=1.000005
DT12
e
ions
B=0.15 TStarting ConditionsR= 0.5 mmR’ () 2.5 Rad
D. Raparia 2003/3/10-11MAC Review
LEBT Simulation in Two Parts Extraction/acceleration and LEBT simulation has been done in two part(1) extraction/ acceleration and grid lens are electrostatic and are simulated with AXCEL with full space charge(2) Later part of the LEBT consist of solenoid lens is simulated with TRACE with linear space charge
Electrostatic
ElectrostaticAXCEL
MagneticTrace
D. Raparia 2003/3/10-11MAC Review
LEBT ElectrostaticV1 V2
V3
V4 V5 V6
Electrode Voltage (kV)Extraction/Acceleration
V1 -8
V2 +76
V3 0
Grid Lens
V4 0
V5 -21
V6 0
17 kev/u
4 keV/u
15 keV/u
5 kev/u
Au+32
D. Raparia 2003/3/10-11MAC Review
LEBT Solenoid
B=7.8 kGL=37.1 cm
R (mm)
Np
•Scrivens @ CERN has reportedhollow beam in solenoid transport(Reproduced this in our codes)• Codes did not show hollow beam for our case
R (mm)
Np
R (mm)
Np
TRACE2D
E=8.5 keV/u,I=2mA
D. Raparia 2003/3/10-11MAC Review
Beam Parameters at End of LEBTIons E
(MeV)Curr(mA)
Tran(%)
X-XP5 rms, Unnor, ( mm mrad)
Y-YP5 rms, Unnor, ( mm mrad)
Au+32 3.2 10.0 100 1.06 0.063 125 1.06 0.06 125
Au+31 3.1 10.0 100 0.994 0.063 125 0.994 0.063 125
Au+30 3.0 10.0 100 1.111 0.094 125 1.111 0.094 125
Au+33 3.3 10.0 100 1.118 0.057 125 1.118 0.057 125
Au+34 3.4 10.0 100 1.432 0.119 125 1.432 0.119 125
He+2 0.68 10 100 1.06 0.064 125 1.60 0.064 125
Phase space ellipses at end of the LEBTFor different charge state of gold
D. Raparia 2003/3/10-11MAC Review
RFQ Parameters
Parameters BNL CERN Units
Type 4-rod 4-rod
Q/m 0.16-0.5 0.12
Energy in 17.0 2.5 keV/amu
Energy out 300 250 keV/amu
Frequency 101.28 101.28 MHz
Max rep rate 5 10 Hz
Length 4.37 2.5 Meters
# of cells 277
Aperture 0.005 .0045 Meters
Voltage 69 70 kV
E (surface) 20.8 23 MV/m
RF Power < 350 < 350 kW
Acceptance 1.7 > 0.8 mm mrad (nor)
Input Emit. 0.35 mm mrad, nor, 90%
Output Emit. (trans) 0.375 mm mrad, nor, 90%
Output Emit. (longit) 32.5 MeV deg
Transmission 91 93 %
Bravery factor 1.8 2 Kilpatrick
-Proven technology, No risks-Can accelerate He- Au(Present thinking- collaboration Frankfurt on a 4-rod RFQ
D. Raparia 2003/3/10-11MAC Review
RFQ Beam Dynamics DesignPARMTEQ
Transmission:Au+32 91% (10 mA)
4He+2 91 % (10 mA)
3He+2 88% (2 mA)P 65% (2 mA)
D. Raparia 2003/3/10-11MAC Review
Beam envelopes for Au+31
(example of neighboring charge state)
D. Raparia 2003/3/10-11MAC Review
RFQ TransmissionTransmission vs Input Emittance
0
20
40
60
80
100
0 100 200 300 400 500
emitt unnor, 90% (pi mm mr)
tran
smis
sio
n (
%)
Transmission vs. Input Energy
0
50
100
0 5 10 15
Input Energy Error (keV)
Tra
nsm
issi
on
(%
)
Transmission vs. Charge State
0102030405060708090
100
28 29 30 31 32 33 34
Charge State of Au
Tra
nsm
issi
on
(%
)
Transmission vs. Input Current
60
70
80
90
100
0 10 20 30 40
Input Current (mA)
Tra
nsm
issi
om
(%
)
RFQ transmission vs Input Emittance RFQ transmission for different charge state of gold
RFQ transmission vs input voltage error(Nominal operating voltage 100 kV)
RFQ Transmission vs input Current
D. Raparia 2003/3/10-11MAC Review
Long. Emittance Growth vs Energy Spread
Long. Emit Growth vs energy spread
0
0.5
1
1.5
2
0 5 10 15
Half energy Spread (kV)
Em
it.
Gro
wth
D. Raparia 2003/3/10-11MAC Review
Twiss Parameters at End of RFQIons Energy
(MeV)Curr(mA)
Tran(%)
X-XP5 rms, Unnor ( mm mrad)
Y-YP5rms,Unnor,( mm mrrad)
5 rms, MeV deg)
(m)
(m)
(deg/MeV)
Au+32 62.00 10 91 1.8 0.180 24 -1.59 0.142 22.5 -0.22 13.3 32.5
Au+31 61.08 10 86 1.6 0.152 27 -1.25 0.138 20.5 -0.04 27.1 40.3
Au+30 62.08 10 55 1.6 0.162 30 -1.16 0.138 20 0.97 27.5 105
Au+33 61.87 10 58 1.5 0.164 26 -1.05 .108 21 -0.08 17.2 40.9
Au+34 10 0 He+2 1.259 10 91 1.7 0.28 24.5 -0.86 0.117 25.5 -0.13 615.9 1.055
X-XP Plane Y-YP Plane Plane
Simulation show no emittance growth for Au+32
D. Raparia 2003/3/10-11MAC Review
Requirements for MEBT-Matching from FODO (RFQ) to axial symmetric IH structure with Solenoids-Diagnostics; Current monitor(2) , Emittance
Twiss parameters at beginning and end of the MEBT
Parameters End of RFQ Entrance of IH Units
X 1.8 1.802
X 0.18 1.01 mm/mrad
X (5* rms,unnorm) 24 24 mm mrad
Y -1.39 0.60
Y 0.142 0.59
Y (5* rms,unnorm) 22 22 mm mrad
Z 0.054 0.59
Z 0.0203 0.0009 deg/keV
Z (5* rms,unnorm)Au+32 34168 34168 deg keV
D. Raparia 2003/3/10-11MAC Review
Space Charge In MEBT
Energy = 300 keV/u=0.025272=1.000319R= 3 mmI=5 mA
Z A Q Q/m EPS*(un) Perv(gen) ET SCT Ratio Debye LenP 1 1 1 1.00 24 1.99351E-05 0.0196 0.0066 0.33916 0.0019
He3 2 3 2 0.67 24 1.32901E-05 0.0196 0.0044 0.226107 0.002328D 1 2 1 0.50 24 9.96754E-06 0.0196 0.0033 0.16958 0.002688Si 14 28 12 0.43 24 8.54361E-06 0.0196 0.0028 0.145354 0.002903Au 79 197 32 0.16 24 3.23819E-06 0.0196 0.0011 0.055092 0.004715
* EPS(N, rms)=0.125
D. Raparia 2003/3/10-11MAC Review
Transport from RFQ to Linac(5 quads, 1 buncher)
Q1 (pmq) 101 T/mQ2 (EM) 33 T/mQ3 (EM) 38 T/mQ4 (EM) 36 T/mQ5 (EM) 38 T/mB1 150 kV
EM quads same as SNS MEBT quads
Au+32
XI= 1.8*0.9 + 1.5*0.86 + 1.5*0.58* + 1.2*.55 + 0.8*.24=4.6 mAAu+32 Au+31 Au+33 Au+30 Au+29
D. Raparia 2003/3/10-11MAC Review
IH Linac
Main parameters of the IH linac Parameters BNL CERN Tank 1 Units
Q/m 0.18-0.5 0.12
Input energy 0.300 0.250 MeV/amu
Output Energy 2.0 1.87 MeV/amu
Frequency 101.28 101.28 Mhz
Max rep rate 5 10 Hz
length 4.0 3.57 Meters
Input emittamce 0.55 pi mm mrad, norm,98%
Output emittance 0.66 pi mm mrad, norm,98%
Output energy spread 20.0 keV/amu
transmission 100 %
IH Linac very similar to the first tank of the CERN Pb linac, is our baseline:,
(Present thinking – collaboration with GSI on an IH Linac)
D. Raparia 2005/01/27-28EBIS Review
IH linac optics codes LORAS used in this preliminary design
Transverse profiles in the IH linac
Longitudinal profiles in the IH linac
Au+32
Current = 4.6 mA
D. Raparia 2005/01/27-28EBIS Review
IH Linac Input and Output Emittances
Au+32
Input Output N, 98% N, 98% %X-XP( mm mrad) .55 .66 20Y-YP ( mm mrad) .54 .67 24(( ns/keV/u) .92 1.32 41
I=4.6 mA
D. Raparia 2005/01/27-28EBIS Review
Beam envelopes for Au+30
Longitudinal profiles in the IH linac
Transverse profiles in the IH linac
(example of neighboring charge state)
D. Raparia 2005/01/27-28EBIS Review
Twiss Parameters End of LinacIons Curr.
(mA)Trans.(%)
X-XPUnnorm, 5rms
( mmmr)
Y-YPUnnorm, 5 rms
(mmmr)
5 rms( MeV deg)
(m)
(m)
(deg/MeV)
Au+32 4.6 100 2.1 1.97 11.0 -1.59 3.45 10.3 -0.68 5.4 35.0
Au+31 4.6 55.8 1.01 0.60 41.0 0.025 1.47 31.3 5.21 14.5 90.72
Au+30 4.6 0 Au+33 4.6 85 1.77 2.73 11.2 -1.12 3.61 10.0 0.71 3.5 54.8
Au+34 He+2 10 85 1.56 1.0 10.44 0.28 1.5 9.7 0.8 1.2 15
X-XP Plane Y-YP Plane Plane
Current Out =1.8*0.9*1.0 + 1.5*0.86*0.56 + 1.5*0.58*0.85=3.1 mA
D. Raparia 2005/01/27-28EBIS Review
Emittance for LinacEnergy
(keV/u)
Accpt.
(N) ( mm mrad)
Transverse (N, rms) ( mm mrad)
Longitudinal
(5 rms)
Simulation
Input
Simulation
Output
MeV deg
kev/u
EBIS 5 0.0033 0.110 0.125 - -
LEBT 17 0.0060 0.125 0.125 - -
RFQ 300 0.025 1.7 0.125 0.125 32.5 3
IH Linac 2000 0.065 4.3 0.125 0.153 35.0 20
Inflector 2000 0.065 1.9 0.153 0.153 35.0 1.8*
(Au+32)
*Booster requirement 2keV/uMeasurements: 0.1 (N, rms) ( mm mrad)Au+25 (all charge states) 1.7 mA
Though simulations show only 22% transverse emittance growth, we have designed for 100% emittance growth from EBIS to Booster.
D. Raparia 2005/01/27-28EBIS Review
Continue Part II
D. Raparia 2005/01/27-28EBIS Review
Superconducting Linac Option-Allow acceleration of higher energies(> 6MeV/u for q/m=0.5) for higher q/m ions-Base on ALPI, ISAC-II and RIA, Technology-Two type of cavity ~0.04 and 0.08
The ALPI resonator
Optimization of for maximum energy gain per cavity
D. Raparia 2005/01/27-28EBIS Review
SCL ParametersParameter Values Units
Q/m 0.16-0.67
Input energy 0.300 MeV/amu
Output Energy 2-7.5 MeV/amu
Frequency 101.28 MHz
Max rep rate 10 Hz
Input emittance 0.55 mm mrad, norm,90%
Output emittance
~ 0.6 mm mrad, norm,90%
Transmission 100 %
-Accelerating Gradient 7MV/m-Helium Consumption >7 Watt at 4.2K / resonator-Energy gain 5MeV/charge/cryostat-Three cryostats to produce 15 MeV for the SCL
D. Raparia 2005/01/27-28EBIS Review
TRACE Simulation for SCL(AU)
4.000 mm X 15.000 mrad
5.000 Deg X 999.00 keV
4.000 mm X 15.000 mrad
5.000 Deg X 999.00 keV NP2= 78
5.00 mm (Horiz) 180.0 Deg (Long.)
5.00 mm (Vert)
NP1= 1
Length= 6308.40mm
1 2 G 3 4 G 5 6
7 SOL
8 9 10 G 11 12 G 13 14 15 G 16 17 G 18 19
20 SOL
21 22 23 G 24 25 G 26 27 28 G 29 30 G 31 32
33 SOL
34 35 36 G 37 38 G 39 40 41 G 42 43 G 44 45
46 SOL
47 48 49 G
50
51 G 52
53 54 G
55
56 G 57 58
59 SOL
60 61 62 G
63
64 G 65
66 67 G
68
69 G 70 71
72 SOL
73 74 75 G
76
77 G 78
H A= 0.0000 B= 0.30000 V A= 0.0000 B= 0.30000
Z A= 0.0000 B= 1.74800E-02
BEAM AT NEL1= 1 H A= 3.23052E-02 B= 0.88380 V A= 3.23052E-02 B= 0.88380
Z A= 0.90204 B= 2.67026E-03
BEAM AT NEL2= 78 I= 1.7mA W= 59.6543 507.8899 MeV
FREQ= 101.28MHz WL=2960.04mm EMITI= 14.000 14.000 43.70 EMITO= 6.368 6.368*********
N1= 1 N2= 78 PRINTOUT VALUES PP PE VALUE 1 2 0.41468 2 2 -33.00000 2 4 45.60000 2 6 0.00000 2 8 0.00000 1 11 3.00000 MATCHING TYPE = 0
CODE: TRACE3D v66L FILE: ebislin8.txt DATE: 02/27/2004 TIME: 14:36:26
D. Raparia 2005/01/27-28EBIS Review
TRACE Simulation for SCL(D)
4.000 mm X 15.000 mrad
60.000 Deg X 999.00 keV
4.000 mm X 15.000 mrad
90.000 Deg X 999.00 keV NP2= 78
5.00 mm (Horiz) 180.0 Deg (Long.)
5.00 mm (Vert)
NP1= 1
Length= 6308.40mm
1 2 G 3 4 G 5 6
7 SOL
8 9 10 G 11 12 G 13 14 15 G 16 17 G 18 19
20 SOL
21 22 23 G 24 25 G 26 27 28 G 29 30 G 31 32
33 SOL
34 35 36 G 37 38 G 39 40 41 G 42 43 G 44 45
46 SOL
47 48 49 G
50
51 G 52
53 54 G
55
56 G 57 58
59 SOL
60 61 62 G
63
64 G 65
66 67 G
68
69 G 70 71
72 SOL
73 74 75 G
76
77 G 78
H A= 0.0000 B= 0.30000 V A= 0.0000 B= 0.30000
Z A= 0.28427 B= 0.94670
BEAM AT NEL1= 1 H A=-0.37302 B= 0.42335 V A=-0.37302 B= 0.42335
Z A= 122.94 B= 81.048
BEAM AT NEL2= 78 I= 0.0mA W= 0.6056 13.4873 MeV
FREQ= 101.28MHz WL=2960.04mm EMITI= 14.000 14.000 90.00 EMITO= 2.962 2.962 90.00
N1= 1 N2= 78 PRINTOUT VALUES PP PE VALUE 1 2 0.41468 2 2 -10.00000 2 4 29.30000 2 6 0.00000 2 8 0.00000 1 11 3.00000 MATCHING TYPE = 0
CODE: TRACE3D v66L FILE: EBSLING9.txt DATE: 02/27/2004 TIME: 09:51:37
D. Raparia 2005/01/27-28EBIS Review
Slop =0.92
L
2R
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