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Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Alex Bogacz
Dogbone configuration
orbit separation
simultaneous acceleration of both + - species
12.5 GeV Two-step-Dogbone RLA
Quadrupole focusing scheme – Triplet vs FODO lattices
multi-pass linac optics
‘droplette’ Arcs
matching to the Arcs
5 GeV Dogbone RLA (3.5 pass) – Complete lattice design, sensitivity studies
15 GeV Dogbone RLA (6.5 pass)?
Dogbone RLA – Design Choices
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Simultaneous acceleration of both + species
E
E0
E0 + (n+½)E
orbit separation, energy difference between consecutive passes: 2E
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
12.5 GeV Two-step-Dogbone RLA
2 GeV to 5 GeV 5 GeV to 12.5 GeV
the same energy ratio for both dogbones:
2 GeV0.3 GeV
1 GeV/pass5 GeV
2 GeV/pass12.5 GeV
Ef
E0
= 2.5
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
12.5 GeV Two-step-Dogbone RLA
2 GeV to 5 GeV 5 GeV to 12.5 GeV
the same energy ratio for both dogbones:
2 GeV0.3 GeV
1 GeV/pass5 GeV
2 GeV/pass12.5 GeV
Ef
E0
= 2.5
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Injection double-chicane
900
Wed Apr 26 00:28:03 2006 OptiM - MAIN: - D:\ISS_dogbone\Chicane\Chicane_dogleg.opt
30
0
2-2
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Initial beam emittance/acceptance after cooling at 273 MeV/c
Study IIb rmsA = (2.5)2
normalized emittance: x/y mmrad 4.8 30
longitudinal emittance: l
lp z/mc)
momentum spread: p/p
bunch length: z
mm
mm
27
0.07
176
150
0.17
442
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Pre-accelerator different style cryo-modules
Short Medium Long
Number of periods 12 18 22
Total length of one period 3 m 5 m 8 m
Number of cavities per period
1 1 2
Number of cells per cavity 1 2 2
Cavity accelerating gradient 15 MV/m 15 MV/m 15 MV/m
Real-estate gradient 3.72 MV/m 4.47 MV/m 5.59 MV/m
Aperture in cavities (2a) 460 mm 460 mm 460 mm
Aperture in solenoids (2a) 460 mm 460 mm 460 mm
Solenoid length 1 m 1 m 1 m
Solenoid maximum field 1.5 T 1.9 T 3.9 T
460
1000
3000
200
1000 500
200 460
1500
5000
250
1000 500
500 500
460 1500
8000
1500 250
1000 500
500 500
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Introduction of synchrotron motion in the initial part of the linac
0 100 200 3000
10
20
30
40
50
60
70
80
90
s[m]
RF
pha
se [
deg]
0 100 200 3000
1
2
s [m]
Syn
chro
tron
pha
se/2
PI
100 0 100
0.2
0
0.2
Phase [deg]
Dp/
p
0 50 100 150 200 250 3000
0.5
1
1.5
2
s [m]
Ene
rgy
[GeV
]
p/p=0.17or =93 (200MHz)
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
25-25 S [cm] View at the lattice end
20
0-2
00
dP
/P *
10
00
,
25-25 S [cm] View at the element 275
20
0-2
00
dP
/P *
10
00
,
Linear Pre-accelerator – Longitudinal dynamics
25-25 S [cm] View at the lattice beginning
20
0-2
00
dP
/P *
10
00
,
3020
Fri Dec 03 11:22:15 2004 OptiM - MAIN: - D:\Study 2A\PreLinac\Linac_sol.opt
25
0
30
-90
Be
tatr
on
siz
e X
&Y
[cm
]
An
gle
[de
g][
-90
,+9
0]
a b Angle[deg]
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Symmetric ‘Dogbone’ RLA (3.5-pass) Scheme
Main Linac (2 GeV/pass)
3 ‘droplet’ Arcs based on periodic cells (900 betatron phase advance per cell)
Dogbone RLA - footprint
-5000
-3000
-1000
1000
3000
5000
-15000 -10000 -5000 0 5000 10000 15000 20000 25000 30000 35000
z [cm]
x [cm]
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
120
Mon Aug 28 23:06:16 2006 OptiM - MAIN: - D:\RLA explore\Cells\Triplet.opt
300
50
BE
TA_X
&Y
[m]
DIS
P_X
&Y
[m]
BETA_X BETA_Y DISP_X DISP_Y120
Mon Aug 28 23:09:19 2006 OptiM - MAIN: - D:\RLA explore\Cells\FODO.opt
30
0
50
BE
TA_
X&
Y[m
]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
FODO vs Triplet focusing structure
FODO Triplet
Advantages:
much weaker quads (~3 times)shorter quads (total)easier chromaticity correction
Advantages:
longer straight sectionssmaller vertical beta-functionuniform variation of betas and
dispersion
The same length
The same phase advance per cell (x= 900 = y)
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design ChoicesTriplet - ‘flat focusing' linac profile
‘half pass’ , 2-3 GeV
1-pass, 3-5 GeV
mirror symmetry cond. (outn = in
n+1,and outn = -in
n+1, n - pass index)
Initial phase adv/cell 90 deg – constant quad grarients for the entire linac
phase adv. drops much faster in the horizontal plane
124.310
Mon Aug 28 23:31:09 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac05.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
124.310
Mon Aug 28 23:29:40 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac05.opt
30
0
50
BE
TA_
X&
Y[m
]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
256.820
Mon Aug 28 23:36:36 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac1.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
256.820
Mon Aug 28 23:35:11 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac1.opt
60
0
50
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices Triplet - ‘flat focusing' linac profile
2-pass, 5-7 GeV
3-pass, 7-9 GeV
mirror symmetry cond. (outn = in
n+1,and outn = -in
n+1, n - pass index)
256.820
Mon Aug 28 23:40:53 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac2.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
256.820
Mon Aug 28 23:39:54 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac2.opt
12
00
50
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
256.820
Mon Aug 28 23:44:16 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac3.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
256.820
Mon Aug 28 23:43:18 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac3.opt
12
00
50
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
phase adv. drops much faster in the horizontal plane
no phase adv. in the horizontal plane
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design ChoicesFODO - ‘flat focusing' linac profile
‘half pass’ , 2-3 GeV
1-pass, 3-5 GeV
mirror symmetry cond. (outn = in
n+1,and outn = -in
n+1, n - pass index)
initial phase adv/cell 90 deg – fixed gradient in all cells
phase adv. drifting uniformly in both planes
122.150
Mon Aug 28 09:15:16 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac05.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
248.6510
Mon Aug 28 09:18:21 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac1.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
248.6510
Mon Aug 28 09:16:24 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac1.opt
30
0
50
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
122.150
Mon Aug 28 09:13:44 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac05.opt
30
0
50
BE
TA_
X&
Y[m
]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices FODO - ‘flat focusing' linac profile
2-pass, 5-7 GeV
3-pass, 7-9 GeV
mirror symmetry cond. (outn = in
n+1,and outn = -in
n+1, n - pass index)
248.6510
Mon Aug 28 09:21:27 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac2.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
248.6510
Mon Aug 28 09:20:00 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac2.opt
60
0
50
BE
TA_
X&
Y[m
]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
248.6510
Mon Aug 28 09:30:55 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac3.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
248.6510
Mon Aug 28 09:30:00 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac3.opt
60
0
50
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices FODO - ‘flat focusing' linac profile
4-pass, 9-11 GeV
5-pass, 11-13 GeV
mirror symmetry cond. (outn = in
n+1,and outn = -in
n+1, n - pass index)
248.6510
Mon Aug 28 09:38:19 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac4.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
248.6510
Mon Aug 28 09:37:37 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac4.opt
90
0
50
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
248.6510
Mon Aug 28 09:43:05 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac5.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
248.6510
Mon Aug 28 09:42:15 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac5.opt
90
0
50
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices ‘flat focusing' linac profile
6-pass, 13-15 GeV
mirror symmetry cond. (outn = in
n+1,and outn = -in
n+1, n - pass index)
248.6510
Mon Aug 28 09:49:14 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac6.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
248.6510
Mon Aug 28 09:48:09 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac6.opt
90
0
50
BE
TA_
X&
Y[m
]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Phase slippage in the linac
avk
1
Ncavi
b k ib k i 1
Ebk i 1
b k ih
360
1
2
m
Ebk i
2
Ebk i h Ek
Ef0 Ea0
b7 0 0b5 0 0b3 0 0b1 0 0
b6 0 0b4 0 0b2 0 0b0 0 0Ebk 0 Eak mb k 0 0
i 0 Ncav 1hLlinac
Ncav
Ek
Eak 1 Eak
Llinac
j 0 8Ncav 80k 0 7Llinac 24000
0 1 104
2 104
20
0
20
s [m]
RF
pha
se [
deg]
0 1 104
2 104
3 104
0
5
10
s [m]
RF
pha
se [
deg]
1refi
b2 i 2refi
b3 i
E0 = 2 GeV E0 = 2 GeV
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Arc 1 Layout
Arc dipoles
$Lb=150; => 150 cm$ang0=10.3283; => 10.328 deg$Nin=16; => 16$Nout=2; => 2$ang=(90+$ang0)/($Nin-2*$Nout); => 8.36 deg.#$Ang_out=$ang0+2*$Nout*$ang; => 43.77 deg.$Ang_in=2*$Nin*$ang; => 267.54 deg.
$BP=$PI*$Hr*$ang/(180*$Lb); => 6.537
kGauss
$Lring=227.3 m
footprint
-5000
-4000
-3000
-2000
-1000
0
1000
2000
3000
4000
5000
0 2000 4000 6000 8000 10000
z [cm]
x [cm]
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Droplet Arc – Optics ‘Building Blocks’
900 phase advance/cell: inward and outward cells, missing dipole, empty cells
90
Fri Dec 03 13:23:10 2004 OptiM - MAIN: - D:\Study 2A\Droplette\A_out.opt
30
0
3-3
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]BETA_X BETA_Y DISP_X DISP_Y 90
Fri Dec 03 13:24:34 2004 OptiM - MAIN: - D:\Study 2A\Droplette\A_out.opt
30
0
3-3
BE
TA_
X&
Y[m
]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
90
Fri Dec 03 13:27:09 2004 OptiM - MAIN: - D:\Study 2A\Droplette\L_out.opt
30
0
3-3
BE
TA_
X&
Y[m
]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y 4536
Fri Dec 16 13:01:21 2005 OptiM - MAIN: - D:\Study 2A\Droplette\SprTr.opt
30
0
3-3
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
footprint
-5000
-4000
-3000
-2000
-1000
0
1000
2000
3000
4000
5000
0 2000 4000 6000 8000 10000
z [cm]
x [cm]
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
237.30
Fri Jan 20 13:16:02 2006 OptiM - MAIN: - M:\acc_phys\bogacz\ISS_dogbone\Lattice\Arc1.opt
0.5
0P
HA
SE
_X
&Y
Q_X Q_Y
Arc 1 – Mirror-symmetric Optics
dipoles (2 per cell)
$Lb=150; => 150 cm$ang0=10.3283 deg
$ang=(90+$ang0)/($Nin-2*$Nout); =>
8.36 deg
$B=$PI*$Hr*$ang/(180*$Lb); => 6.537
kGauss
quadrupoles (triplet):L[cm] G[kG/cm] 68 -0.326125 0.328 68 -0.326
16 cells2 cells 2 cells
(out = in ,and out = -in , matched to the linacs)
237.30
Fri Jan 20 13:12:52 2006 OptiM - MAIN: - M:\acc_phys\bogacz\ISS_dogbone\Lattice\Arc1.opt
30
0
3-3
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
$Nout=2, need minimum of 3 triplets to match 6 Twiss parameters
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Straight-Arc Periodic transition
1170
Wed Nov 30 01:22:41 2005 OptiM - MAIN: - D:\ELIC\Figure-8\tran.opt
20
0
0.2
5-0
.25
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
Triplet
FODO
1080
Wed Dec 07 10:30:44 2005 OptiM - MAIN: - D:\ELIC\Figure-8\FODO\low_emitt\spr_in.opt
30
0
2-2
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
15 GeV Dogbone RLA (6.5 pass)
energy ratio:
2 GeV0.3 GeV
Ef
E0
= 7.5
2 GeV/pass15 GeV
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
15 GeV Dogbone RLA (6.5 pass)
energy ratio:
2 GeV0.3 GeV
Ef
E0
= 7.5
2 GeV/pass15 GeV
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Beam Separation Switchyard
footprint
0
20
40
60
80
100
0 50 100 150 200 250 300 350 400 450 500
z [cm]
x [cm]
5 GeV9 GeV
13 GeV
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy
Thomas Jefferson National Accelerator Facility NuFact’06, UC Irvine, August 29, 2006.
Alex Bogacz, Dogbone RLA – Design Choices
Summary
‘Dogbone’ RLA – preferred configuration better orbir separation for higher passes
offers symmetric solution for simultaneous acceleration of + and -
FODO lattice more favorable (compared to the triplet) to
accommodate large number of passesuniform phase advance decrease in both planes
smaller variation of Twiss function – easier match to the Arcs
Proposed 12.5 GeV two-step-dogbone RLA (30 mm rad
acceptance)
3.5 pass 5 GeV Dogbone (triplet lattices) – error sensitivity studiesMagnet misalignment error analysis (DIMAD Monte Carlo on the above
lattice) shows quite manageable level of orbit distortion for ~1 mm
level of magnet misalignment error.
Great focusing errors tolerance for the presented lattice 1% of Arc-to-
Arc betatron mismatch limit sets the quadrupole field spec at 0.2%
Aggressive 15 GeV dogbone RLA
Recommended