heavy-ion beam dynamics in the ria accelerators and ...€¦ · p.n. ostroumov, “heavy-ion beam...

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P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 1 Heavy-Ion Beam Dynamics in the RIA Accelerators and Development of RT Accelerating Structures for the RIA Layout of the RIA accelerators. Acceleration of multiple-charge state heavy-ion beams. Driver Linac: - Injector system: ECR-LEBT-RFQ; - Design of 57.5 MHz cw RFQ; - Parametric resonance of transverse motion; - Beam steering compensation and electric field symmetry in SRF cavities; - Beam Dynamics optimization and simulation; - Isopath transport of multi-q beams; - BD in hi gh- section: Triple-Spoke vs Elliptical cavities. Design of the Post-Accelerator: - RT accelerating structures and beam dynamics. Summary and outlook.

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Page 1: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 1

Heavy-Ion Beam Dynamics in the RIA Acceleratorsand Development of RT Accelerating Structures for the RIA

• Layout of the RIA accelerators.• Acceleration of multiple-charge state heavy-ion beams.• Driver Linac:

- Injector system: ECR-LEBT-RFQ;- Design of 57.5 MHz cw RFQ;- Parametric resonance of transverse motion;- Beam steering compensation and electric field

symmetry in SRF cavities;- Beam Dynamics optimization and simulation;- Isopath transport of multi-q beams;- BD in high-E section: Triple-Spoke vs Elliptical cavities.

• Design of the Post-Accelerator:- RT accelerating structures and beam dynamics.

• Summary and outlook.

Page 2: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 2

Rare Isotope Accelerator Facility

4007373He

100 (400)400238U

400451136Xe

400900p

Beam power (kW)

Beam energy (MeV/u)

Species

Page 3: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3

Beam

Beam

f, MHz 57.5 57.5 57.5 115 172.5 345

f, MHz 805 805 805

Page 4: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 4

ANL spoke cavity

JLABellipticalcavity

Page 5: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 5

Acceleration of synchronous particle

sc0us TLeEA

qW M' cos,

Aq

constEconstE

A

q00 /

,

0n

qsnsn0n

EA

qconst

constEA

qn ,cos,cos MM

0s0

snn

A

q

A

q,coscos MM

Fixed velocity profile(RFQ, RT DTL)

Multi-q heavy-ionaccelerator

Variable velocity profile(SC Linac)

E0=const,Tune phases of individual cavities

Page 6: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 6

-60

-50

-40

-30

-20

-10

0

65 70 75 80 85 90

Charge state

Pha

se (

deg)

Synchronous phase as a function of uranium ion charge state. The designed synchronous phase is

–30q for q0=75.

Page 7: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 7

E0

q=75

Ms

Eg(z)

-0.15 -0.1 -0.05 0 0.05 0.1 0.15

Distance, m

Zt

q=77

q=73

Earlier arrival Later arrival

Single accelerating gap

Page 8: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 8

' p /p , % 2 q = 7 7 q = 7 5 1 q = 7 3 0 -1 -2 -8 0 -4 0 0 4 0

P hase , d e g

-0.8

-0.4

0

0.4

0.8

-15 -10 -5 0 5 10 15

Phase (deg)

'p

/p (

%)

q=77 q=75 q=73

Separatrix and small longitudinal oscillations

Page 9: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 9

xxxx

xxxxx

xxxxx

xxxx

M

HEDJ

PDPPJ

PEPDP

c�c�

»¼

º«¬

ª��

22 2

sincossin

sinsincos

Lf

SRF cavitiesSolenoid

Transverse beam dynamics

Page 10: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 10

54

56

58

60

62

64

72 73 74 75 76 77 78

Charge state

Pha

se a

dvan

ce

Px

(deg

)

0

100

200

300

400

500

Pha

se a

dvan

ce

)x

(deg

)

Px

)x

Phase advance over the period Px and total phase advance )x (modulo 360 q) in the medium-beta

section (12 MeV/u – 85 MeV/u)

Page 11: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 11

0

10

20

30

40

1 2 3 4 5 6 7 8 9 10

Emittance growth factor

N/N

0, %

Transverse emittance growth in the focussing channel with alignment errors (±300 Pm)

Corrective one-element steering

No steering

Page 12: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 12

Stripping foil

ECR ion source

Booster Injector

ATLAS section

Diagnostic area

40q Bend Reg ion

Slits, Faraday Cup

Multi-q beam experiment on ATLAS (ANL)

W=1.2 MeV/uq=35,36,37,38,39,40,41,42,43,44

W=2.9 MeV/u

q_average=51

Page 13: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 13

-3

-2

-1

0

1

2

3

-30 -20 -10 0 10 20 30

Phase, deg

'W

/W, %

35+

36+

37+

38+

39+

40+

41+

42+

43+

Beam Dynamics Simulations

0

0.25

0.5

0.75

1

1.25

0 400 800 1200 1600

Distance, cmB

ea

m s

ize

, cm

35+ 36+37+ 38+39+ 40+41+ 42+43+

Page 14: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 14

35 36 37 38 39 40 41680

690

700

710

Measurement

Simulation

Bea

m E

nerg

y (M

eV)

Charge State

Multi-q beam energy at the exit of the Booster

Equivalent to the RIA design req.

Page 15: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 15

0.00

0.05

0.10

0.15

0.20

0.25

35 36 37 38 39 40 41 42 43 44

Charge state

Nor

mal

ized

cur

rent

(re

l. va

lue)

94% Transmission of Multi-Q Accelerated Beam Through the Booster

Page 16: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 16

Accelerating and Focusing Lattice of the Driver Linac

Focusing:• In the DTL: superconducting solenoids.• In the high-E linac: warm SNS-type quadrupole

doublets (baseline design) or SC solenoids.• Length of focusing period is determined by the

stability conditions and required small beam size for high-intensity ion linacs:

- DTL: Raperture/R rms_beam= 11-12- High-E linac: Raperture/R rms_beam= 20-25

Acceleration:

• Superconducting resonators except in the Front End.

Page 17: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 17

Layout of the Driver Linac

Front End

RFQ LEBTMEBT

Low-E

High-E

Medium-E

Page 18: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 18

Low-energy achromatic 120° bend

Phase space plots

-10 -8 -6 -4 -2 0 2 4 6 8 10

-30

-20

-10

0

10

20

30

Ex=E

y =100p mm*mrad

y plane

x (bending) planex|,y| mrad

x,y mm

B

-6 -4 -2 0 2 4 6

-40

-30

-20

-10

0

10

20

30

Q=29

Q=28

Ex=124pmm*mrad x

| ,mrad

X ,mm

-12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12

-15

-10

-5

0

5

10

15

Q=29

Q=28

Ey=132 pmm*mrad

y| ,mrad

y ,mm

Page 19: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 19

Longitudinal phase space plots of two-charge state uranium beam along the LEBT

21

20

q1

q1

1

cAm

eV22

L�

O

Page 20: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 20

�CW regime;

� Wide dynamic range of rf power level from P0/70 to P0for acceleration of various ion species from protons to uranium;

� Simultaneous acceleration of two charge-state heavy-ion beams;

� Maintaining an extremely small longitudinal emittance formed by the external multi-harmonic buncher;

� Exit of the RFQ: beam waist in both H- and V-planes for easer matching to the following MEBT.

Basic features of the 57.5 MHz RFQ

Page 21: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 21

• Adiabatic bunching;• Internal ‘klystron’ bunching;• External multi-harmonic buncher: Extremely low long.

emittance (ISAC-1 RFQ, TRIUMF). Simultaneous acceleration of 2 charge states for heavy ions.

RFQ design options

a) High-efficiency SRF cavities for the following acceleration;

b) Moderate peak surface fields in the RFQ to provide reliable operation in CW mode;

c) High quality two-charge-state beam parameters;d) Large transverse acceptance.e) Possibility to increase inter-vane voltage to accept lower

charge states (higher intensities!).

Frequency is 57.5 MHz:

Page 22: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 22

Accelerating by an RFQ

2

1

2

2

0

EO

EO

S

cL

m

aR

k

ma

a - Aperture

- Maximum distance from axis to electrodes

Page 23: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 23

RFQ resonant structure

~4000

I 510

Page 24: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 24

Vane Tip

¸¹

ᬩ

§��

¸¹

ᬩ

§��

kzsin1m

1m1Ry

kzsin1m

1m1Rx

0

0

eR2

Longitudinal modulationTransverse cross-section

Page 25: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 25

-2 -1 0 1 20

1

2

3

4

5

6

Ele

ctric

fie

ld (

MV

/m)

Distance from RFQ center (m)

-2 -1 0 1 2-8

-6

-4

-2

0

2

4

6

8

Ele

ctric

fie

ld (

MV

/m)

Distance from RFQ center (m)

Electric field distribution along the RFQ

f=57.5 MHz

Absolute

Ex Ey

Operating mode f=57.5 MHz

Upper mode 1 f=68.4 MHz

f=93.5 MHz

Page 26: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 26

Cross Section of the Octagonal ResonatorS

= 5

13

S = 513

Internal dimension

Page 27: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 27

� �����

����> @

������

�����> @

�����

����> @

�����

����> @

57.5 MHz RadioFrequency QuadrupoleAccelerator

Page 28: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 28

RF Induced Heat Flux

Heat FluxW/cm2

Heat flux distribution determined with ANSYS RF analysis, heat loads scaled to 8.0 kW per segment

0.0 1.84 2.76 3.68 4.60 5.52 6.44 7.36 8.28.92

Page 29: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 29

Radial displacements of Vanes at symmetry plane

Radial Displacementinches

-1.94e-3 inches

-2.58e-4

-1.91e-3

-2.59e-4

-1.94e-3 -1.73e-3 -1.51e-3 -1.30e-3 -1.08e-3 -8.62e-4 -6.46e-4 -4.29e-4 -2.14e-4 2.30e-6

Path 1this vane at tipstart this sidesee next slide

Path 2this vane at tipstart this sidesee next slide

Page 30: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 30

Characteristics of the RFQ resonator

• Modular structure. The brazing technique which is well established for 4-vane RFQs can be applied. Brazing provides the best electrical properties of rf structures;

• Small transverse dimensions for low frequencies;• Large frequency separation of non-operating modes;• Uniform field distribution along the z-axis;• High shunt impedance (45 kW for 4 meter structure);• Symmetric design guarantees low field perturbations

due to possible thermal distortion, no dipole component of the fields in the aperture;

• Provides good mechanical stability of the construction together with precise alignment ability.

Page 31: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 31

¦

¦

¦

¦ ¦

f

��

f

��

f

f

f

���

���

��¸̧¹

·¨̈©

§

»¼

º«¬

ª�����

042,1212

0)12(212,22

0

)12(2

012,00

1 112202

4cos])12[(),(

)12(2cos)2(),(

)12(2cos),(

)12cos(),(2cos),(),(),,(

mmmnn

mmmnn

m

m

m

n nnn

U

mkrnIArF

mnkrIArF

mR

rArF

kznrFnkzrFrFzrU l

-T

TT

TT

T-T-

104

AT �

S

- Accelerating efficiency

01

2

02

0

2

4A

Rcm

UeK l

¸¸¹

·¨¨©

§�

O- Focusing efficiency

Electric potential in RFQ aperture

Page 32: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 32

Coupling of Longitudinal and Transverse Motions

Separatrix of longitudinal oscillationscalculated at the beginning of the RFQ(k=2.38)

� �� �)sin(Icos2

),H( 00

02

ss zkkrzkAW

TZeUcz MM

S

EE �'�'�

' ''

-8 -4 0 4

-0.2

-0.1

0.0

0.1

'E 1

03

'z (mm)

R=0.4 mm

R=0.25 mm

R=0

Initial particle distribution

sEEE � ' Difference between particle velocity and synchronous value

czzz � ' The corresponding difference between longitudinal coordinates

EO

S2 k

Page 33: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 33

Longitudinal emittances at the exit of RFQ

Phase (deg) Phase (deg)

Phase (deg) Phase (deg)

'W

/W (

%)

'W

/W (

%)

'W

/W (

%)

'W

/W (

%)

1 2

3 4

0.5 1.0 1.5

1.4

1.6

1.8

2.0

2.2

2.4

2.6

Norm. transverse emittance (S mm mrad)

Out

put l

ong.

em

ittan

ce

( S k

eV/u

nse

c)1

2

3

4

Longitudinal emittance99.9 % of particles

50000 particles are simulated

Page 34: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 34

Transverse Emittances at the RFQ Exit

-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4

-0.01

0.00

0.01

0.02

dX/d

z (m

rad)

X (cm)-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3

-0.01

0.00

0.01

0.02

dY/d

Z (

mra

d)Y (cm)

X plane Y plane

-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4

-0.01

0.00

0.01

0.02

dX/d

z (m

rad)

X (cm)-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3

-0.01

0.00

0.01

0.02

dY/d

Z (

mra

d)Y (cm)

X plane Y plane

Page 35: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 35

BEAM RESONATOR TYPE 2-GAP QWR, EG=0.062, f=57.5 MHz 2-GAP QWR, EG =0.15, f=115 MHz

BEAM

BEAM

RESONATOR TYPE

2-GAP HW, EG=0.19,f=172.5 MHz

4-GAP SPOKE, EG =0.5,f=345 MHz

BEAM

BEAM

3.98 m

BEAM

5.80 m

4-GAP SPOKE, EG =0.5, 0.62f=345 MHz

RIA Driver Linac

Page 36: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 36

Driver Linac

400-580177-250113-177Length of the focusing period, cm

46 (38)2010Number of cryostats

805 (345)172.5-34557.5-115Frequency, MHz

105

52

129

20

10.1-85.0

Medium E

28.520Surface field SRF cavities, MV/m

260 (197)55Length, m

46 (38)42Number of focusing periods

166 (140)85Number of resonators

81.0-403.00.2-10.2Uranium beam energy, MeV/u

High ELow E

Page 37: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 37

Some design solutions � Multi-q beam acceleration.� Low longitudinal emittance of two charge-state uranium beam.� Inter-cryostat space will contain only vacuum valves and a small beam

diagnostics box. � Beam steering coils will be combined with the SC focusing solenoids

and will not require an additional space along the beamline.� Standard accelerating SRF cavities can be switched to the mode of a

beam phase monitor in order to set up phases and amplitudes of the accelerating fields in the upstream cavities.

� Transverse matching between the cryostats is facilitated by the absence of the first SRF cavity in the very first focusing period of the cryostats.

� Long. matching between the cryostats is provided by the setting of phases in the SRF cavities.

� Beam energy at stripper locations is determined from the condition of lowest possible long. emittance of multi-q uranium beam.

� Triple spoke cavities vs elliptical.

Page 38: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 38

Simulation codes • TRACE, TRANSPORT, COSY, GIOS;

• CST Microwave Studio; SIMION;

• DESRFQ, DYNAMION;

• RAYTRACE, TRACK.

TRACK:

• multiparticle simulation of multi-q ion beams in 6D phase space;

• 3D electromagnetic fields from MWS in rectangular mesh;• Fringing fields of magnets and multipoles as in RAYTRACE code;

• Realistic fields in solenoids;

• Integration of equations of motion by 4th order Runge-Kutta method;

• Misalignments and random errors are included.

Detailed BD simulations are necessary for cost-effective design of the accelerators

Page 39: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 39

Beam envelopes along the driver linac

Page 40: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 40

The condition for a n-th orderparametric resonances of transverse motion in a smooth approximation lt 2

nPP

Resonance width sn2tsn ba 'P' ��

� � 2u

sm2f

3ss

scm

sineES1

A

q

2

M

OJE

S' Defocusing factor

sl 2 'P

n=1 and Ms=30q: a1| 0, b1|1.79n=2 a2| 3.93, b2|4.31.

Longitudinal phase advance

Parametric resonance

Page 41: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 41

0 100 200 300 400

20

40

60

80

100

n=2

n=1

Pha

se a

dva

nce

(de

g)

Beam Energy (MeV/u)

EG=0.49

EG=0.62

EG=0.81

0 100 200 300 400

20

40

60

80

100

n=2

n=1

Pha

se a

dva

nce

(de

g)

Beam Energy (MeV/u)

EG=0.49

EG=0.62

EG=0.81

Page 42: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 42

0

1

2

3

4

0 10 20 30 40 50 60 70

Distance (m)E

mitt

ance

gro

wth

fact

or

Hz

Hx

Hy

RMS emittance, Pt=30q

Emittance containing99.9% of the particles

DTL section, 172. 5 MHz

0

1

2

3

4

0 10 20 30 40 50 60 70

Distance (m)

Em

ittan

ce g

row

th fa

ctor

Pt =30°

Pt =50°Pt =40°

Win=10 MeV/u

Page 43: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 43

Emittance evolution along the ECL linac for 4-cavity and 3-cavity lattices

1

1.1

1.2

1.3

0 10 20 30 40 50 60 70 80 90

Distance (m)

Em

ittan

ce g

row

th fa

ctor

3-cavity

4-cavity

$90 tP

Emittance evolution along the ECL linac for 4-cavity and 3-cavity lattices

1

1.1

1.2

1.3

0 10 20 30 40 50 60 70 80 90

Distance (m)

Em

ittan

ce g

row

th fa

ctor

3-cavity

4-cavity

$90 tP

BEAMBEAMProposed latticefor the first sectionof the ECL (EG=0.49)

Page 44: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 44

0 5 10 15 20 25 30 35 40-12

-10

-8

-6

-4

-2

0

2

4

6

8

10

12

Hx

Ez

10*Ey

Distance (cm)

10*E

y, Ez (

MV

/m)

-8

-6

-4

-2

0

2

4

6

8

Hx (

kA/m

)

Beam steering in QWR*

*A. Facco&V. Zviagintsev PAC91, N. Kakutani et al in EPAC98

Beam

Page 45: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 45

D727 D(G�D(I�D+

dz)kzsin()z(E-C2/L

2/Lyd0Ed ³ �

MD

dz)kzsin(z

)z(E

2

Cy 2/L

2/L

z00Ef ³ �

w

w

MD

dz)kzcos()z(HCc2/L

2/Lx00H ³ �

MPED

Beam center deflection angles in QWR

Page 46: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 46

0 5 10 15 20 25 30 35 40-12

-10

-8

-6

-4

-2

0

2

4

6

8

10

12

Hx

Ey

Ez

D istance (cm )

Ey,

Ez (

MV

/m)

-8

-6

-4

-2

0

2

4

6

8H

x (kA

/m)

Compensation of the beam-steering effect(1) By cavity displacement in vertical plane: useful for heavy ions,

accepted as a baseline design for the ISAC-II(2) By reshaping of the drift tubes: universal far all regimes.

Page 47: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 47

-1.2

-0.8

-0.4

0

0.4

0.05 0.15 0.25 0.35

E

Def

lect

ion

angl

e (m

rad)

Without compensation

With compensation

Beam steering in QWR

Page 48: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 48

Defocusing asymmetry in 106 MHz QW SRF resonator, EEG=0.085, q/A=1

-0.5

0

0.5

1

1.5

2

2.5

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14

beta

Def

ocus

ing

angl

e (m

rad)

x=1mm

(-y-0+y2_)/2

Defocusing field asymmetry in DT SRF cavities*

*Details will be presented in EPAC2002 by B. Laxdal, P.N. Ostroumov and M. Pasini.

Beam

Page 49: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 49

Defocusing angles in 57.5 MHz QW SRF resonator, EEG=0.062, q/A=1

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14

beta

Def

ocus

ing

angl

e (m

rad)

x=1mm

(y1_75mm-y-0_25mm)/2

Defocusing field symmetry in DT SRF cavities

Page 50: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 50

QUADRUPOLE COMPONENT OF TRANSVERSERF ELECTRIC FIELD

0 5 10 15 20 25

-50000

0

50000

EI

quad

Er

quad

Er

axial

Er,E

I , V/cm r=2/3R

a

z ,cm

Harmonic analysis of the electric field along the axis of HWR in cylindrical coordinates

)2sin(21

)2cos(22

)2cos(

22

2020

222

220

I

I

I

I rAr

V

rE

rArAr

VE

rArAV

r

� w

w�

� w

w�

��

Page 51: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 51

Longitudinal phase space, W=199 keV/u

Input beam, 2 charge states:100% of particles2.4 S keV/u-nsec0.5 S mm-mrad

Page 52: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 52

0

0.25

0.5

0.75

1

1.25

1.5

0 10 20 30 40 50 60Distance (m)

Bea

m s

ize

(cm

)

Yrms

Ymax

Yerror

Cavity aperture

Beam envelopes along the prestripper section

Page 53: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 53

0

5

10

15

20

1 1.2 1.4 1.6 1.8 2 2.2 2.4

Emittance growth factor

N/N

0 (%

)

RMS emittance growth of two-charge state uranium beam in themisaligned focusing channel of low-E linac with the steering correction.

Page 54: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 54

Compact 9 Tesla SC Magnet Assembly

-2

0

2

4

6

8

10

-30 -20 -10 0 10 20 30

Distance (cm)

Mag

netic

Fie

ld (

T)

Higher current in the bucking coils

Lower current in the bucking coils

Focusing by SC solenoids:- proven technology with SC resonators; - multi-q beam is less sensitive to mismatched conditions;- the fringing fields can be suppressed by bucking coils;- alignment of the solenoids should be easier;- beam is less sensitive to solenoid misalignments.

Page 55: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 55

1

2

3

4

5

0 10 20 30 40 50 60

Distance (m)

Long

itudi

nal r

ms

emitt

ance

(4S

keV

/u-n

sec)

q=28.5

q=28 and 29

Longitudinal emittance along the prestripper linac

Page 56: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 56

-2.00E-04

0.00E+00

2.00E-04

-1.20E-01 0.00E+00 1.20E-01

phase (rad)

' 'W

/W (

%)

q=69 q=73

Particle trajectories in the longitudinal phase space

Synchronous phase

Page 57: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 57

Longitudinal phase space, W=9.4 MeV/u

10 S keV/u-nsec

Page 58: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 58

29 S keV/u-nsec

Phase space plots of 5 charge state uranium beam at the location of second stripper linac

85 MeV/u

Page 59: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 59

-20 -10 0 10 20-0.50

-0.25

0.00

0.25

0.50

Ene

rgy

Spr

ead

(%)

Phase (deg of 805 MHz)

Phase space plots of four charge state uranium beam at the exit of the driver linac. Includes all rf field errors and multiplicity

of charge states throughout whole SC Linac

Page 60: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 60

-1 0 1 2 3 4 5 6 7 8-1

0

1

2

3

4

5

6

7

8

Dis

tanc

e (m

)

Distance (m)

Q1,2

SRF

B8

B7

B6

B5B

4B3

B2

B1

Q8Q

3

Q9,10

Q6,7

Q4,5

0 2 4 6 8 10 12 14 16 18

-40

-30

-20

-10

0

10

20

30

40

q=90q=88-92

B7,8

B5,6SRFB

3,4B

1,2

Q9,10

Q8

Q6,7

Q4,5

Q3

Q1,2

y (mm)

x (mm)

s (m)

System for selecting multiple q state beams through a 180° bend at 80 MeV/u.

Page 61: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 61

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

-6-5-4-3-2-10123456 q=91

q=90 q=89

l (mm)

GK (x10-3)

-3 -2 -1 0 1 2 3

-3

-2

-1

0

1

2

3 q=91 q=90 q=89

y (mm)

b (mrad)

-3 -2 -1 0 1 2 3

-3

-2

-1

0

1

2

3 q=91 q=90 q=89

x (mm)

a (mrad)

-15 -10 -5 0 5 10 150

2

4

88899091Z=92

x ,mm

Page 62: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 62

Main sources of longitudinal emittance growth:- Multiplicity of charge state (different synchronous

phase, frequency jumps);- Random errors of rf field;- Passage through the stripper;- Coupling of r-z motion in the RFQ.

Main sources of transverse emittance growth:

- Coherent oscillations of multi-q beams due to the misalignment of focusing elements;

- Mismatch of multi-q beam;- Passage through the stripper;- Higher-order distortions in the post-stripper transport

systems.

Page 63: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 63

RMS emittance growth of multi-q uranium beamin the driver Linac

1.831.05High-E

12.34.4TOTAL

1.041.12Stripper 2

5.241.95Medium-E

1.11.06Stripper 1

1.121.80Low-E

LongitudinalTransverse

Page 64: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 64

Triple Spoke vs Elliptical

MS=-30o MS=-25o

BEAM

3.98 m

BEAM

5.80 m

Page 65: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 65

Triple Spoke vs Elliptical

ECL TSCL Number of cavity types 3 2 Peak surface field (MV/m) 27.5 28. Frequency (MHz) 805 345 Total number of cavities 188 140 Number of cryostats (focusing periods) 47 38 Length in the tunnel (m) 260 200 Operating temperature (qK) 2.1 4.5 Synchronous phase (deg) -30 -25 Longitudinal acceptance (keV/u-nsec) 60 280 Aperture diameter (mm) 80 40 Transverse normalized acceptance (S mm-mrad) 70 35

Page 66: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 66

0

0.4

0.8

1.2

1.6

2

0 50 100 150 200

Distance (m)

Bea

m s

ize

(cm

)

rms size

Maximum size

Cavity aperture

0

5

10

15

20

25

0 50 100 150 200

Distance (m)

Pha

se (

deg)

rms width

(full width)/2

Synchronous phase

Page 67: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 67

12

11

10

5 9

1 2 3 4 6 7 8

6.9 –20 MeV/u

0.68 –2.0 MeV/u

� ² ,VREDU VHSDUDWRU� � ² +LJK YROWDJH SODWIRUP�� � �� 0+] 5)4� � ² �� 0+] +\EULG 5)4�� ² KHOLXP VWULSSHUV� � � �� 0+] +\EULG 5)4�� ² 6& /LQDF EHWZHHQ WKH VWULSSHUV�� ² FDUERQ VWULSSHU� � ² EHDPV WR DVWURSK\VLFV

H[SHULPHQWV� �� ² 6& ERRVWHU OLQDF��� ² $7/$6� �� ² KLJK HQHUJ\ EHDPV�

Page 68: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 68

$FFHOHUDWLQJ�VWUXFWXUHIRU�WKH�+\EULG�5)4�I �������0+]

���8��

9 ����N93FDOFXODWHG ���N:/ ����P:LQM ���NH9�X:H[LW ���NH9�X

Page 69: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 69

Page 70: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 70

Particletrajectories in the Hybrid RFQ

Page 71: Heavy-Ion Beam Dynamics in the RIA Accelerators and ...€¦ · P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 3 Beam Beam f, MHz 57.5 57.5

P.N. Ostroumov, “Heavy-Ion Beam Dynamics in the RIA Accelerators” , October 25, 2002 71

Summary

• The technique of multi-q beam acceleration and transport is understood well;

• A detailed design has been developed for the focusing-accelerating lattice of the RIA accelerators;

• Substantial progress has been made in beam dynamics studies in the SRF DTL;

• Detailed BD studies in the driver linac taking into account errors and misalignments have been carried out;

• Several design concepts related to the driver linac have been successfully tested on the existing SC linac ATLAS.