ess-bilbao initiative workshop. beam dynamics codes: availability, sophistication, limitations

Beam Dynamics Codes: Availability, Sophistication,

Limitations …

P.N. Ostroumov and B. Mustapha

Argonne National Laboratory

J.-P. Carneiro

Fermi National Accelerator Laboratory

ESS Bilbao Initiative WorkshopMarch 16-18, 2009

Bilbao, Spain

ESS-Bilbao Workshop Beam Dynamics Codes … P. Ostroumov 2

Outline

Beam Dynamics Codes: History and Evolution

General Comments: Codes Availability, Sophistication, Limitations

Comparing Codes to Measurements: An example

Our Side of the Story: Comparing TRACK to few other Codes

Summary & Recommendations to the Users

Presentation of TRACK, If interested- General Presentation - Sample TRACK Applications- Recent & Future Developments


Beam Dynamics Codes: History (From R. Ryne’s Talk at HB-2008 Workshop)

1970 1980 1990Transport

2000

MaryLieDragt-Finn

MAD

PARMILA2D space charge

PARMELAPARMTEQ

IMPACT-ZIMPACT-TML/ISynergiaOPALORBITTRACKDynamionDESRFQBeamPathBeamBeam3DMAD-X/PTC…

CODES, CAPABILITIES & METHODOLOGIES FOR BEAM DYNAMICS SIMULATION IN ACCELERATORS

Freq maps

MXYZPTLKCOSY-INF

rms eqns

Normal FormsSymp Integ

DAGCPIC

3D space charge

WARP

SIMPSONS IMPACT

Partial list only; Many codes not shown

Integrated Maps


Beam Dynamics Codes: Evolution(From R. Ryne’s Talk at HB-2008 Workshop)

1970 1980 1990Transport

2000

MaryLieDragt-Finn

MAD

PARMILA2D space charge

PARMELAPARMTEQ

IMPACT-ZIMPACT-TML/ISynergiaOPALORBITTRACKDynamionDESRFQBeamPathBeamBeam3DMAD-X/PTC…

CODES, CAPABILITIES & METHODOLOGIES FOR BEAM DYNAMICS SIMULATION IN ACCELERATORS

Freq maps

MXYZPTLKCOSY-INF

rms eqns

Normal FormsSymp Integ

DAGCPIC

3D space charge

WARP

SIMPSONS IMPACT

Partial list only; Many codes not shown

Integrated Maps

3D COLLECTIVE SELF-CONSISTENT

MULTI-PHYSICS

SINGLE PARTICLE OPTICS

1D, 2D COLLECTIVE

Par

alle

lizat

ion

beg

ins


General Comments: Codes Availability, Sophistication, Limitations

Availability: Many useful beam dynamics codes exist for the simulation of proton and heavy ion linacs …- The variety is good but comes also with redundancy …- A lot of effort is put on benchmarking different codes …

Sophistication: A lot of them are pretty sophisticated- 3D External and Space Charge Fields.- Parallel Codes: Simulation of the actual number of particles in a beam bunch 1E9, 1E12 particles.- Detailed machine error simulations and correctionsLimitations: Still far from reproducing experimental data or to be used to support real-time machine operations.- Some effort is starting at SNS, J-PARC, GSI, …- At Argonne, TRACK is being developed in this direction ...


Example of Code-Code and Code-Experiment Benchmarking: (From L. Groening (GSI), Talk at HB-2008 Workshop)

Schematic set-up of the experiments

Horizontal phase space plots at the DTL exit. Left: σo =35◦; centre: σo =60◦; right: σo =90◦. The scale is ± 24 mm (horizontal axis)

± 24 mrad (vertical axis)

Comparison: 3 Codes vs experiments

Initial Distribution: Measured in front of DTL Reconstructed and Input to Simulations

Horizontal Vertical

The 6D Distribution is parameterized to reproduce the measured 2D projections on phase space planes


Our Experience: TRACK versus few other Codes

TRACK

Ions & electrons

Multi-beam

Support any element

1D,2D,3D fields

3D Poisson

Fast

Serial/Parallel

Errors + Corrections

IMPACT

Ions & electrons

Multi-beam

Most elem. No RFQ

1D, 2D,3D fields

3D Poisson

Fast

Serial/Parallel

Errors + corrections

ASTRA

Electrons & (H-)

Single beam

Less elem. No RFQ

1D, (3D) fields

3D Poisson

2-3x slower

Serial only

Errors only

PARMILA

Ions -

Single beam

Most elem. No RFQ

Hard-edge 2D fields

2D Poisson

Fast

Serial only

Errors only

TRACEWIN

Ions -

Single beam

Most elem. Calls toutatis

3D fields -

2-3D Poisson

Fast

Serial/-

Errors + corrections


RIA Driver Linac Beam Dynamics: TRACK vs IMPACT

-0.2

0

0.2

Xc (

mm

)

-0.2

0

0.2

Yc (

mm

)

0

0.5

Δφc (

deg)

-0.1

0

0.1

X’ c (

mra

d)

0

0.1

Y’ c (

mra

d)

1

2

Δφrm

s (de

g)

0.5

1

Xrm

s (m

m)

0.5

1

Yrm

s (m

m)

2.5

5

7.5

Δφm

ax (

deg)

2

4

6

Xm

ax (

mm

)2

4

6

Ym

ax (

mm

)

50

100

ΔWrm

s (ke

V/u

)

0.09

0.095

0.1

ε xrm

s (m

m*m

rad)

0.09

0.095

0.1

ε yrm

s (m

m*m

rad)

20

40

60

ε zrm

s (de

g*ke

V/u

)

0

10

0 50 100Z-distance (m)

α x

0

2


α y

-2

0

2


α z

X-X’ plane Y-Y’ plane Δφ-ΔW plane

-3

-2

-1

0

1

2

3

-2 2X (mm)

X’

(mra

d)

-3

-2

-1

0

1

2

3

-2 2X (mm)

X’

(mra

d)

-3

-2

-1

0

1

2

3

-2 2Y (mm)

Y’

(mra

d)

-3

-2

-1

0

1

2

3

-2 2Y (mm)

Y’

(mra

d)

-150

-100

-50

0

50

100

150

-3 3Δφ (deg)

ΔW (

keV

/u)

-150

-100

-50

0

50

100

150

-3 3Δφ (deg)

ΔW (

keV

/u)

IMPACT TRACK IMPACT TRACK IMPACT TRACK

RIA driver linac,Medium-β section

Beam: U-2385Q: 72, 73, 74, 75, 76

In W ~ 12 MeV/uOut W ~ 90 MeV/uIn f = 115 MHzOut f = 345 MHz

IMPACT: BlackTRACK : Blue

Excellent agreement is obtained.References:

“RIA Beam Dynamics: Comparing TRACK to IMPACT”, B. Mustapha et al, PAC-05“The RIAPMTQ/IMPACT Beam Dynamics Simulation Package”, T. Wangler et al, PAC-07


FNAL Proton Driver Beam Dynamics: TRACK vs ASTRA

Reference: “Benchmarking of Simulation Codes TRACK and ASTRA for the FNAL High-Intensity Proton Source”, J.-P. Carneiro, LINAC-06.

FNAL-PD Linac: RFQ to Linac end

Beam: 0 mA H-In: W ~ 2.5 MeV, Out: W ~ 8 GeV

ASTRA: Solid curvesTRACK: Dotted curves

Good agreement overall.

FNAL-PD Linac: RFQ to Linac end

Beam: 45 mA H-In: W ~ 2.5 MeV, Out: W ~ 8 GeV

ASTRA: Solid curvesTRACK: Dotted curves

Good agreement overall.


SNS RFQ Beam Dynamics: TRACK vs PARMTEQ

References:“End-to-end Simulation of the SNS Linac using TRACK”, B. Mustapha et al, LINAC-08.

TR

AC

KP

AR

MT

EQ

99.63

0.211

0.213

Parmteq

105.86ε-z (deg-keV)

0.203ε-y (mm-mrad)

0.204ε-x (mm-mrad)

TRACKEmittance: N-RMS

SNS-RFQ: 32 mA H-, 1M particles simulated


SNS Linac Beam Dynamics: TRACK vs PARMILA

“First TRACK Simulations of the SNS Linac”, B. Mustapha et al, LINAC-06.

TR

AC

K

PA

RM

ILA

-0.2

0

0.2

x 10-3

Xc (

cm)

-0.2

0

0.2

x 10-3

Yc (

cm)

0

50

Wc

(MeV

/u)

0

0.2

Xrm

s (cm

)

0

0.2

Yrm

s (cm

)

0

10

20

30

Δφrm

s (de

g)

0.5

1

Xm

ax (

cm)

0.5

1

Ym

ax (

cm)

0

50

ΔWrm

s (ke

V/u

)

0.075

0.1

0.125

4*ε x,

rms

0.075

0.1

0.125

4*ε y,

rms

3

4

5

4*ε z,

rms

0

1

2

ε x,10

0%

0

1

2

ε y,10

0%

0

20

40

ε z,10

0%

-10

0

10

α x

-10

0

10

α y

-5

0

5

α z

0

0.2

0.4


β x

0

0.2

0.4


β y

0

100


β z

X-X’ plane Y-Y’ plane Δφ-ΔW planeSNS linac:DTL section

Beam: 38 mA H-

In W ~ 2.5 MeVOut W ~ 87 MeVIn f = 402.5 MHzOut f = 402.5 MHz

PARMILA: BlackTRACK : Blue

Some differences:- Fringe field in PMQ- SC calculations

References:


SPIRAL-2 Linac Beam Dynamics: TRACK vs TRACEWIN

End-to-end beam dynamics for a 0.5 mA A/q=6 ion beam along the SPIRAL-2 linac from the ion source to end of the linac.

The results were not superposed. But a good agreement between TRACK and TRACEWIN was observed.References:

“Preliminary Conceptual Design of a Heavy-Ion Injector for SPIRAL-2 Linac at GANIL”, Argonne Report to GANIL, unpublished.


Summary and Recommendations to the Users

Summary:Many useful beam dynamics codes exist for the simulation of proton and heavy ion linacs …With different levels of sophistication …But they are still far from reproducing experimental data or to be used to operate an accelerator …

Recommendations to the Users:For consistency: Use 2-3 codes at leastStart with TRACE-3D or a similar envelope codePARMILA & PARMTEQ are good to use because it comes with very good documentationFinal design with error simulations should be done with more advanced codes such as TRACK, IMPACT, TraceWin

ESS-Bilbao Workshop Beam Dynamics Codes … P. Ostroumov

The Beam Dynamics Code: TRACK


The Beam Dynamics Code: TRACK

TRACK Main FeaturesA wide range of E-M elements with 3D fieldsEnd-to-end simulations from source to targetSimultaneous tracking of Multiple charge states ion beamsInteraction of heavy ion beams with strippersAutomatic transverse and longitudinal beam tuningError simulations for all elements: Static and dynamic errorsRealistic correction procedure: Transverse and LongitudinalSimulations with large number of particles for large number of seedsBeam loss analysis with exact location of particle loss

Recent UpdatesPossibility of fitting experimental data: beam profiles, …H- Stripping: Black body, Residual gas and Lorentz strippingThe design and simulation of electron linacs – Genetic optimizationParallel version is fully developed with good scaling up to 32K processorsPossibility of simulating the actual number of particles in a bunch


TRACK: Extensive List of Supported Elements

Any type of RF resonator (3D fields)Static ion optics devices (3D fields)Radio-Frequency Quadrupoles (RFQ)Drift Tube Linacs (DTL)Coupled Cavity Linacs (CCL)Solenoids with fringe fields (model and 3D fields)Bending magnets with fringe fields (model and 3D fields)Electrostatic and magnetic multipolesMulti- Harmonic Bunchers (MHB)Axial Symmetric electrostatic lensesEntrance and exit of HV decksAccelerating tubes with DC voltageTransverse beam steering elementsStripping foils or films for heavy-ion beamsHorizontal and vertical jaw slitsTRACK was heavily used in the design and simulations of the RIA/FRIB and FNAL-PD linacs and recently in the simulation of the SNS linac.


TRACK Application: Design and Simulations of the FRIB Linac

Injector: Two options w/wo MHBRFQ SC LINACMEBT

LEBTECR−IS

LEBT MHB RFQECR−IS SC LINAC

MEBT

100 % Transmission 80% TransmissionLarge long. emittance ~ 8 times smaller emittance

Qua

d

Qua

d

Qua

d

Qua

d

Qua

d

Qua

d

Qua

d

Qua

d

Qua

d

Qua

d

Qua

d

Qua

d

Ben

d

Ben

d

Ben

d

Ben

d

Ben

d

Ben

d

Ben

d

Ben

d

Mul

ti

Mul

ti

Mul

ti

Mul

ti

Bun

ch

Collim

0123456789

10

0 2 4 6 8 10 12 14Z-distance (m)

Xrm

s, Y

rms (

mm

)

Chicane: Collimation and Matching

-2.5-2

-1.5-1

-0.50

0.51

1.52

2.5

-2 0 2x (cm)

x’ (

mra

d)

-2.5-2

-1.5-1

-0.50

0.51

1.52

2.5

-2 0 2y (cm)

y’ (

mra

d)

-0.5-0.4-0.3-0.2-0.1

00.10.20.30.40.5

-10 0 10φ (deg)

ΔW/W

(%

)

-2.5-2

-1.5-1

-0.50

0.51

1.52

2.5

-2 0 2x (cm)

x’ (

mra

d)

-2.5-2

-1.5-1

-0.50

0.51

1.52

2.5

-2 0 2y (cm)

y’ (

mra

d)

-0.5-0.4-0.3-0.2-0.1

00.10.20.30.40.5

-10 0 10φ (deg)

ΔW/W

(%

)

Error simulations: Before and after Corrections

Different RF jitter errors: 0.5, 1 and 2 (deg, %)

-3

-2

-1

0

1

2

3

-2 0 2x (cm)

x’ (

mra

d)

-3

-2

-1

0

1

2

3

-2 0 2y (cm)

y’ (

mra

d)

-1.5-1

-0.5

00.5

1

1.5

-50 0 50φ (deg)

ΔW/W

(%

)

-3

-2

-1

0

1

2

3

-2 0 2x (cm)

x’ (

mra

d)

-3

-2

-1

0

1

2

3

-2 0 2y (cm)

y’ (

mra

d)

-1.5-1

-0.5

00.5

1

1.5

-50 0 50φ (deg)

ΔW/W

(%

)

-3

-2

-1

0

1

2

3

-2 0 2x (cm)

x’ (

mra

d)

-3

-2

-1

0

1

2

3

-2 0 2y (cm)

y’ (

mra

d)

-1.5-1

-0.5

00.5

1

1.5

-50 0 50φ (deg)

ΔW/W

(%

)

No corrections

Corrections

0.5 deg, 0.5 %

1.0 deg, 1.0 %

2.0 deg, 2.0 %


TRACK Application: Design and Simulations of the FNAL-PD

Error simulations: 100 seeds, 1M particles each

0 deg0 %

1 deg1 %

2 deg2 %

Beam Emittances: before and after RF errors

Beam Envelopes

Beam Loss: Different RF errors

0.1

0.2

0.3

0.4

0.5

0 100 200 300 400 500 600 700Z distance (m)

4*ε x-

rms (

cm-m

rad)

0.1

0.2

0.3

0.4

0.5

0 100 200 300 400 500 600 700Z distance (m)

4*ε y-

rms (

cm-m

rad)

0

20

40

0 100 200 300 400 500 600 700Z distance (m)

4*ε z-

rms (

keV

/u-n

s)

0.1

0.2

0.3

0.4

0.5

0 100 200 300 400 500 600 700Z distance (m)

4*ε x-

rms (

cm-m

rad)

0.1

0.2

0.3

0.4

0.5

0 100 200 300 400 500 600 700Z distance (m)

4*ε y-

rms (

cm-m

rad)

0

20

40

0 100 200 300 400 500 600 700Z distance (m)

4*ε z-

rms (

keV

/u-n

s)

1 deg1 %

1

2

3

0 100 200 300 400 500 600 700Z distance (m)

Xm

ax (

cm)

1

2

3

0 100 200 300 400 500 600 700Z distance (m)

Ym

ax (

cm)

0

10

20

30

40

0 100 200 300 400 500 600 700Z distance (m)

φ max

(de

g)

1

2

3

0 100 200 300 400 500 600 700Z distance (m)

Xm

ax (

cm)

1

2

3

0 100 200 300 400 500 600 700Z distance (m)

Ym

ax (

cm)

0

10

20

30

40

0 100 200 300 400 500 600 700Z distance (m)

φ max

(de

g)

10-2

10-1

1

0 100 200 300 400 500 600 700Distance (m)

Los

t po

wer

(W

/m)

10-2

10-1

1

0 100 200 300 400 500 600 700Distance (m)

Los

t po

wer

(W

/m)

10-1

1

10

0 100 200 300 400 500 600 700Distance (m)

Los

t po

wer

(W

/m)

123 4 5 6 7

0 deg0 %

1 deg1 %

0 deg0 %

Fraction: 2E-5Peak: 0.1 W/m

Fraction: 1E-4Peak: 0.4 W/m

Fraction: 3E-2Peak: 35 W/m

Table:Errors and their typical values

See Paper in LINAC-06


TRACK Application: End-to-end Simulation of the SNS Linac

RFQ Simulations Linac simulations from MEBT to HEBTEnvelopes: rms, max Emittances: 4*rms

Phase space plots

Transmission is consistent within ±1%

LINAC-08

Envelopes: rms, max Emittances: 4*rms

Phase space plots

Next steps- Error and beam loss simulations- Compare with experimental data


TRACK Application: Design and Simulations of an electron linac

Layout of a linac for a future X-Ray FEL Oscillator

2 deg2 %

Energy spread

Bunch widthBeam Simulations

1 2 3 4 5 6 7 8 9 10 11 12 131 2 3 4 5 6 7 8 9 10 11 12 13

1- RF cavity with thermionic cathode, 100 MHz, 1 MV; 2- chicane and slits; 3- as an energy filter; 4- quadrupole triplet; 5- focusing solenoid; 6- monochromator of the beam energy, f=600 MHz; 7- buncher, f=300 MHz; 8- booster linac section, f=400 MHz; 9- RF cosine-chopper to form rep. rate 1 MHz to 100 MHz; 10- bunch compressor – I; 11- SC linac section, 460 MeV, f=1300 MHz; 12- bunch compressor – II; 13- initial section of the SC linac, f=1300 MHz.

See Paper in LINAC-08

0.001

0.01

0.1

1

10

0 20 40 60 80 100 120

Distance (m)

RM

S e

nerg

y sp

read

(M

eV)

Energy Filter

Velocity Buncher

Bunch compressor-I

Bunch compressor-II

Monochromator

0.1

1

10

100

1000

0 20 40 60 80 100 120

Distance (m)

Bun

ch R

MS

wid

th (

psec

)

Energy Filter

Velocity Buncher

Bunch compressor-I

Bunch compressor-II

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0 2 4 6 8 10 12

Distance (m)

Em

ittan

ce (

m)

ExEy Emittance


TRACK Application: Realistic Corrective Steering in HINS Linac

Design: the procedure was used to optimize the number, location of monitors and correctors as well as the correctors strengths.

Operations: could be implemented using real beam position monitors and beam steerers.

MonCorr Corr CorrCorr

Mon

MonCorr Corr

Mon

Corr CorrMon

CorrCorrCorrCorr

Virtual monitors and correctors are used

-1

-0.5

0

0.5

1

0 5 10 15 20 25 30 35Z distance (m)

Xct

r (cm

)

-10-505

10

0 5 10 15 20 25 30 35Z distance (m)

X’ ct

r (mra

d)

-1

-0.5

0

0.5

1

0 5 10 15 20 25 30 35Z distance (m)

Yct

r (cm

)

-10-505

10

0 5 10 15 20 25 30 35Z distance (m)

Y’ ct

r (mra

d)

0

20

40

60

80

100

120

140

160

-1250-1000-750 -500 -250 0 250 500 750 1000 1250B*L (G*cm)

Occ

urre

nce

Beam centers and angles before and after corrections

Correctors field strengths

-1

-0.5

0

0.5

1

0 5 10 15 20 25 30 35Z distance (m)

Xct

r (cm

)

-10-505

10

0 5 10 15 20 25 30 35Z distance (m)

X’ ct

r (m

rad)

-1

-0.5

0

0.5

1

0 5 10 15 20 25 30 35Z distance (m)

Yct

r (cm

)

-10-505

10

0 5 10 15 20 25 30 35Z distance (m)

Y’ ct

r (m

rad)

-1

-0.5

0

0.5

1

0 5 10 15 20 25 30 35Z distance (m)

Xct

r (cm

)

-10-505

10

0 5 10 15 20 25 30 35Z distance (m)

X’ ct

r (m

rad)

-1

-0.5

0

0.5

1

0 5 10 15 20 25 30 35Z distance (m)

Yct

r (cm

)

-10-505

10

0 5 10 15 20 25 30 35Z distance (m)

Y’ ct

r (m

rad)

-1

-0.5

0

0.5

1

0 5 10 15 20 25 30 35Z distance (m)

Xct

r (cm

)

-10-505

10

0 5 10 15 20 25 30 35Z distance (m)

X’ ct

r (m

rad)

-1

-0.5

0

0.5

1

0 5 10 15 20 25 30 35Z distance (m)

Yct

r (cm

)

-10-505

10

0 5 10 15 20 25 30 35Z distance (m)

Y’ ct

r (m

rad)

Sensitivity to monitors errors: 10, 30 and 100 μThe number and locations of monitors and correctors are varied until a reasonable correction scheme is obtained.


TRACK Application: Operations of a Multi-Q Injector at ANL

20+21+20+&21+

20+21+20+&21+

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

-6 -4 -2 0 2 4 6X (cm)

a.u.

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

-3 -2 -1 0 1 2 3Y (cm)

a.u.

Measured beam profiles at the end of LEBT: left: horizontal, right: vertical.

Pepper-Pot images: Bi-209 beamsleft: 20+&21+right: 20+: blue, 21+:red.

0

200

400

600

800

1000

1200

1400

1600

1800

-4 -3 -2 -1 0 1 2 3X (cm)

a.u

0

200

400

600

800

1000

1200

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2Y (cm)

a.u.

TRACK fit of measured profiles to extract the initial beam parameters at the source.

TRACK fit to find the quads setting to recombine the two charge state Bi-209 beams at the end of the LEBT.

Such a perfect recombination was not possible without a realistic simulation.


TRACK Application: Automatic Transverse Tuning in RIA Linac

0.05

0.1

0.15

0.2

0.25

Xrm

s (cm

)

0.05

0.1

0.15

0.2

0.25

0 5 10 15 20 25 30 35 40 45 50Z-distance (m)

Yrm

s (cm

)

0.05

0.1

0.15

0.2

0.25

Xrm

s (cm

)

0.05

0.1

0.15

0.2

0.25

0 5 10 15 20 25 30 35 40 45 50Z-distance (m)

Yrm

s (cm

)

Automatic Transverse TuneOriginal Manual Tune

X- and Y-rms beam sizes before and after applying the automatic transverse tuning procedure. The beam is a two-charge state uranium beam in the first section of the RIA/FRIB driver linac.

A similar procedure was developed to produce smooth longitudinal envelopes by fitting the RF cavities field amplitudes and phases.

Purpose: Tune the linac for a given beam and produce smooth transverse beam dynamics.

Method: Minimize the fluctuations in the RMS beam sizes along the considered section.

Fit Function:

where and are the RMS beam sizes at the entrance of the section or after the first focusing period, the sum index i runs over the focusing periods in a given section and and are the allowed errors on the RMS beam sizes.

Fit Parameters: Field strengths in focusing elements

This method is general and should produce good results for both periodic or non periodic accelerating structures.

∑∑ 22

−++−+=i

Y

rmsi

rmsrmsi

X

rmsirms

rms

rmsrms

YYY

XXXF

εε

200

200 )()(

0rmsX 0

rmsY

XrmsεYrmsε

Developed and used for design optimization this procedure could very well be applied to a real machine using beam profile measurements to reduce beam mismatch.


TRACK Application: Longitudinal Fine Tuning before a Stripper

-8

-6

-4

-2

0

2

4

6

8

0 20 40 60 80 100 120Distance (m)

Δφ (

deg)

-100

-75

-50

-25

0

25

50

75

100

0 20 40 60 80 100 120Distance (m)

ΔW (

keV

/u)

-8

-6

-4

-2

0

2

4

6

8

0 20 40 60 80 100 120Distance (m)

Δφ (

deg)

-100

-75

-50

-25

0

25

50

75

100

0 20 40 60 80 100 120Distance (m)

ΔW (

keV

/u)

-300

-200

-100

0

100

200

300

-10 -8 -6 -4 -2 0 2 4 6 8 10Δφ (deg)

ΔW (

keV

/u)

-300

-200

-100

0

100

200

300

-10 -8 -6 -4 -2 0 2 4 6 8 10Δφ (deg)

ΔW (

keV

/u)

Black: Ref. 74+ of U-238Colors: 72+,73+,75+ and 76+

10-2

10-1

1

10

10 2

0 100 200 300 400 500Distance (m)

Los

t po

wer

(W

/m)

10-2

10-1

1

10

10 2

0 100 200 300 400 500Distance (m)

Los

t po

wer

(W

/m)

Purpose: Tune a linac section to minimize the logitudinal emittance of a multiple charge state beam right before stripping.

Method: Match the longitudinal beam centers and Twiss parameters of the different charge state beams:

Fit Function:

where is the desired beam energy and is the corresponding error.

are the allowed errors on the relative energy, phase and shifts of the individual charge state beams from the central beam.

Fit Parameters: RF cavities field amplitudes and phases.

min;0;0;0;00 →→→Δ→Δ→ qiqiqiqiq WWW βαφ

∑∑∑∑ ++Δ+Δ+−= 22Δ

2Δ

qiqi

qi

qi

qi

qi

qiw

qiq WWWF

w

βε

αεφ

εε αφ

222200

2

)(

Measuring the energy and phase of individual charge states, we should be able to match their beam centers, … Reduced beam loss in the high-energy section

0W Wε

αφ εεε ,, ΔΔW

α


P-TRACK Application: One to One RFQ Simulation ~ 1 B particles

Simulated the actual number of particles in 45 mA proton beam at 325 MHz accelerated in a RFQ from 50 keV to 2.5 MeV 865 M particles on 32768 procs.Benefits of simulating a large number of particles: actual number if possible- Suppress noise from the PIC method: enough particles/cell- More detailed simulation: better characterization of the beam halo

Phase space plotsfor 865 M protonsafter 30 cells in theRFQ.

(x, x’) (y, y’) (Δt, ΔW’)

3D beam: 100M


P-TRACK Application: Large Scale Error Simulations 10M/Seed

Simulated machine errors with 10M particles per seed FNAL-PD linac:- ~ 2000 elements, 1.7 Km long- misalignment errors and (1%,1 deg) RF errors- includes H- stripping: Black body, residual gas and Lorentz stripping. Benefits of simulating a large number of particles/seed:- Study beam loss to the lowest possible level.

Envelopes RMS emittances Beam loss

Lost fraction: 9 E-4Peak loss: 0.9 W/m

With H- stripping, the fraction lost increased by almost one order of magnitude Linac &Transfer line should be cooled


Future Developments: Parallel Optimization Tools

So far, the developed optimization tools were used only with the serial version of TRACK Very time consuming.

Large scale parallel computing is necessary for timely optimizations …

The fully parallel version of TRACK is now ready

Next: Test the existing tools with the Parallel version of TRACK

First: Try parallel tracking and serial optimization.

Second: Investigate the use of parallel optimization algorithms developed at the Mathematics and Computer Science division of Argonne (TAO: Toolkit for Advanced Optimization, PETSc).


More Developments Towards a Model Driven Accelerator

More tools are needed to fit the experimental data using a beam dynamics code.

Develop interfaces between the beam diagnostic devices and the beam dynamics code Calibrate and analyze the data to input to the code.

Numerical experiments could be used to test the tools before implementation to the real machine Produce detector like data from the code.

Larger scale realization: ATLAS at ANL, may be SNS Linac …

Large scale parallel computing will be needed to support real time operations of the machine.

ess-bilbao initiative workshop. beam dynamics codes: availability, sophistication, limitations

Technology

useful beam dynamics

codes availability

y mmria beam dynamics

parallel codes

d distribution

d projections

d fieldsfields

ria driver linac beam