Dogbone RLA Design Choices

skillfulbuyerUrban and Civil

Nov 16, 2013 (3 years and 11 months ago)

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Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Alex Bogacz


Dogbone configuration


orbit separation


simultaneous acceleration of both
m
+

m
-

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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Simultaneous acceleration of both
m
+

m
-

species


m
-

m
+

m
+

m
-

m
+

m
-

m
-

m
+

m
-

m
+

m
+

m
-

D
E

E
0

E
0
+ (n+½)
D
b
=
orbit separation, energy difference between consecutive passes: 2
D
E

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

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 GeV

0.3 GeV

1 GeV/pass

5 GeV

2 GeV/pass

12.5 GeV

E
f

E
0

= 2.5

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

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 GeV

0.3 GeV

1 GeV/pass

5 GeV

2 GeV/pass

12.5 GeV

E
f

E
0

= 2.5

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Injection double
-
chicane

90
0
Wed Apr 26 00:28:03 2006 OptiM - MAIN: - D:\ISS_dogbone\Chicane\Chicane_dogleg.opt

30
0
2
-2
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
m
+

m
-

m
+

m
-

m
+

m
-

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Initial beam emittance/acceptance after cooling at 273 MeV/c


Study

IIb

e
rms

A

=

(
2
.
5
)
2

e

normalized

emittance
:

e
x
/
e
y


mm

rad


4
.
8

30

longitudinal

emittance
:

e
l



(e
l

=

s
D
p

s
z
/m
m
c)


momentum

spread
:

s
D
p/p



bunch

length
:

s
z

mm




mm

27


0
.
07

176

150



0
.



442


Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

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

(
2
a
)

460 mm

460 mm

460 mm

Aperture

in

solenoids

(
2
a
)

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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Introduction of synchrotron motion in the initial part of the linac

0
100
200
300
0
10
20
30
40
50
60
70
80
90
s[m]
RF phase [deg]
0
100
200
300
0
1
2
s [m]
Synchrotron phase/2 PI
100
0
100
0.2
0
0.2
Phase [deg]
Dp/p
0
50
100
150
200
250
300
0
0.5
1
1.5
2
s [m]
Energy [GeV]

D
p/p=

0.17or
Df
=

93 (200MHz)


Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.


25
-25
S [cm]
View at the lattice end
200
-200
dP/P * 1000,

25
-25
S [cm]
View at the element 275
200
-200
dP/P * 1000,
Linear Pre
-
accelerator


Longitudinal dynamics


25
-25
S [cm]
View at the lattice beginning
200
-200
dP/P * 1000,
302
0
Fri Dec 03 11:22:15 2004 OptiM - MAIN: - D:\Study 2A\PreLinac\Linac_sol.opt

25
0
30
-90
Betatron size X&Y[cm]
Angle[deg][-90,+90]
a
b
Angle[deg]
Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Symmetric ‘Dogbone’ RLA (3.5
-
pass) Scheme


Main Linac (2 GeV/pass)

3 ‘droplet’ Arcs based on periodic cells (90
0

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]
m
+

m
-

m
+

m
-

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

12
0
Mon Aug 28 23:06:16 2006 OptiM - MAIN: - D:\RLA explore\Cells\Triplet.opt

30
0
5
0
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
12
0
Mon Aug 28 23:09:19 2006 OptiM - MAIN: - D:\RLA explore\Cells\FODO.opt

30
0
5
0
BETA_X&Y[m]
DISP_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 sections

smaller vertical beta
-
function

uniform variation of betas and dispersion



The same length


The same phase advance per cell (
Df
x
= 90
0

=
Df
y
)

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Triplet
-

‘flat focusing' linac profile

‘half pass’ , 2
-
3 GeV





1
-
pass, 3
-
5 GeV





mirror symmetry cond.
(
b
out
n

=
b
in
n+1
,and
a
out
n

=
-
a
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

124.31
0
Mon Aug 28 23:31:09 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac05.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
124.31
0
Mon Aug 28 23:29:40 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac05.opt

30
0
5
0
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
256.82
0
Mon Aug 28 23:36:36 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac1.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
256.82
0
Mon Aug 28 23:35:11 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac1.opt

60
0
5
0
BETA_X&Y[m]
DISP_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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Triplet
-

‘flat focusing' linac profile

2
-
pass, 5
-
7 GeV




3
-
pass, 7
-
9 GeV





mirror symmetry cond.
(
b
out
n

=
b
in
n+1
,and
a
out
n

=
-
a
in
n+1
, n
-

pass index)


256.82
0
Mon Aug 28 23:40:53 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac2.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
256.82
0
Mon Aug 28 23:39:54 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac2.opt

120
0
5
0
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
256.82
0
Mon Aug 28 23:44:16 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac3.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
256.82
0
Mon Aug 28 23:43:18 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_Triplet\flat\Linac3.opt

120
0
5
0
BETA_X&Y[m]
DISP_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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

FODO
-

‘flat focusing' linac profile

‘half pass’ , 2
-
3 GeV





1
-
pass, 3
-
5 GeV





mirror symmetry cond.
(
b
out
n

=
b
in
n+1
,and
a
out
n

=
-
a
in
n+1
, n
-

pass index)


initial phase adv/cell
90 deg


fixed gradient in all cells

phase adv. drifting

uniformly in both planes

122.15
0
Mon Aug 28 09:15:16 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac05.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
248.651
0
Mon Aug 28 09:18:21 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac1.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
248.651
0
Mon Aug 28 09:16:24 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac1.opt

30
0
5
0
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
122.15
0
Mon Aug 28 09:13:44 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac05.opt

30
0
5
0
BETA_X&Y[m]
DISP_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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

FODO
-

‘flat focusing' linac profile

2
-
pass, 5
-
7 GeV




3
-
pass, 7
-
9 GeV





mirror symmetry cond.
(
b
out
n

=
b
in
n+1
,and
a
out
n

=
-
a
in
n+1
, n
-

pass index)


248.651
0
Mon Aug 28 09:21:27 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac2.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
248.651
0
Mon Aug 28 09:20:00 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac2.opt

60
0
5
0
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
248.651
0
Mon Aug 28 09:30:55 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac3.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
248.651
0
Mon Aug 28 09:30:00 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac3.opt

60
0
5
0
BETA_X&Y[m]
DISP_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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

FODO
-

‘flat focusing' linac profile

4
-
pass, 9
-
11 GeV




5
-
pass, 11
-
13 GeV





mirror symmetry cond.
(
b
out
n

=
b
in
n+1
,and
a
out
n

=
-
a
in
n+1
, n
-

pass index)


248.651
0
Mon Aug 28 09:38:19 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac4.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
248.651
0
Mon Aug 28 09:37:37 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac4.opt

90
0
5
0
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
248.651
0
Mon Aug 28 09:43:05 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac5.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
248.651
0
Mon Aug 28 09:42:15 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac5.opt

90
0
5
0
BETA_X&Y[m]
DISP_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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

‘flat focusing' linac profile

6
-
pass, 13
-
15 GeV




mirror symmetry cond.
(
b
out
n

=
b
in
n+1
,and
a
out
n

=
-
a
in
n+1
, n
-

pass index)


248.651
0
Mon Aug 28 09:49:14 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac6.opt

0.5
0
PHASE_X&Y
Q_X
Q_Y
248.651
0
Mon Aug 28 09:48:09 2006 OptiM - MAIN: - D:\RLA explore\Dogbone_FODO\flat\Linac6.opt

90
0
5
0
BETA_X&Y[m]
DISP_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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Phase slippage in the linac

f
av
k
1
N
cav
i
f
b
k
i



=
f
b
k
i
1
+

Eb
k
i
1
+







f
b
k
i

h

360

1
2
m
m
Eb
k
i







2








+
Eb
k
i

h
D
E
k

+










=
Ef
0
Ea
0
=
f
b
7
0

0
=
f
b
5
0

0
=
f
b
3
0

0
=
f
b
1
0

0
=
f
b
6
0

0
=
f
b
4
0

0
=
f
b
2
0

0
=
f
b
0
0

0
=
Eb
k
0

Ea
k
m
m
+
=
f
b
k
0

0
=
i
0
N
cav
1
-

=
h
L
linac
N
cav
=
D
E
k
Ea
k
1
+
Ea
k
-
L
linac
=
j
0
8

=
N
cav
80
=
k
0
7

=
L
linac
24000
=
0
1

10
4
2

10
4
20
0
20
s [m]
RF phase [deg]
0
1

10
4
2

10
4
3

10
4
0
5
10
s [m]
RF phase [deg]
f
1
ref
i
f
b
2
i

=
f
2
ref
i
f
b
3
i

=
E
0
= 2 GeV

D
E
0
= 2 GeV

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Droplet Arc


Optics ‘Building Blocks’


90
0

phase advance/cell: inward and outward cells, missing dipole, empty cells

9
0
Fri Dec 03 13:23:10 2004 OptiM - MAIN: - D:\Study 2A\Droplette\A_out.opt

30
0
3
-3
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
9
0
Fri Dec 03 13:24:34 2004 OptiM - MAIN: - D:\Study 2A\Droplette\A_out.opt

30
0
3
-3
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
9
0
Fri Dec 03 13:27:09 2004 OptiM - MAIN: - D:\Study 2A\Droplette\L_out.opt

30
0
3
-3
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
45
36
Fri Dec 16 13:01:21 2005 OptiM - MAIN: - D:\Study 2A\Droplette\SprTr.opt

30
0
3
-3
BETA_X&Y[m]
DISP_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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

237.3
0
Fri Jan 20 13:16:02 2006 OptiM - MAIN: - M:\acc_phys\bogacz\ISS_dogbone\Lattice\Arc1.opt

0.5
0
PHASE_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


-
0.326

125


0.328

68


-
0.326

16 cells

2 cells

2 cells

(
b
out

=
b
in

,and
a
out

=
-
a
in

, matched to the linacs)

237.3
0
Fri Jan 20 13:12:52 2006 OptiM - MAIN: - M:\acc_phys\bogacz\ISS_dogbone\Lattice\Arc1.opt

30
0
3
-3
BETA_X&Y[m]
DISP_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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Straight
-
Arc
-

P
eriodic transition

117
0
Wed Nov 30 01:22:41 2005 OptiM - MAIN: - D:\ELIC\Figure-8\tran.opt

20
0
0.25
-0.25
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
Triplet

FODO

108
0
Wed Dec 07 10:30:44 2005 OptiM - MAIN: - D:\ELIC\Figure-8\FODO\low_emitt\spr_in.opt

30
0
2
-2
BETA_X&Y[m]
DISP_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

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

15 GeV Dogbone RLA (6.5 pass)

energy ratio:

2 GeV

0.3 GeV

E
f

E
0

= 7.5

2 GeV/pass

15 GeV

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

15 GeV Dogbone RLA (6.5 pass)

energy ratio:

2 GeV

0.3 GeV

E
f

E
0

= 7.5

2 GeV/pass

15 GeV

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

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 GeV

9 GeV

13 GeV

Operated by the Jefferson Science Associates for the U.S. Depart. Of Energy


Thomas Jefferson National Accelerator Facility

Alex Bogacz
,
Dogbone RLA


Design Choices

NuFact’06, UC Irvine, August 29, 2006.

Summary

‘Dogbone’

RLA


preferred configuration

better orbir separation for higher passes

offers symmetric solution for simultaneous acceleration of
m
+

and
m
-

FODO

lattice more favorable (compared to the triplet) to accommodate large
number of passes

uniform 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 studies

Magnet 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