11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

R&D Status of cancer therapy accelerator

PAMELA

Takeichiro Yokoi

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

Particle physics -factory, muon source, proton driver

-factory-factory

FFAGMedical

Particle therapy, BNCT, X-ray source

Particle Particle therapytherapy

FFAG

Energy ADSR, Nucl. Transmutation

ADSRADSRFFAG

CONFORM CONFORM ((Construction of a Non-scaling FFAG for Oncology, Research and Medicine) aims to develop the Non-scaling FFAG as a versatile accelerator. (Project HP: www.conform.ac.uk)

EMMA

PAMELA

(PAMELA)

Introduction ...

• FFAG (Fixed Field Alternating Gradient) Accelerator has the ability of rapid particle acceleration with large beam acceptance. wide varieties of applications

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

• 3 parts of the project are funded

1. EMMA : Construction of electron NS-FFAG as a scaled down model of muon accelerator for neutrino factory

2. PAMELA : Design of proton and HI accelerator for particle therapy using NS-FFAG

3. (other Applications) : ex ADSR (THoreA)

• 3 parts of the project are funded

1. EMMA : Construction of electron NS-FFAG as a scaled down model of muon accelerator for neutrino factory

2. PAMELA : Design of proton and HI accelerator for particle therapy using NS-FFAG

3. (other Applications) : ex ADSR (THoreA)

Project manager : K.Peach (JAI, Oxford university) UK based : Birmingham University Brunel Utility Cockcroft Institute Daresbury Laboratory Gray Cancer Institute Imperial College London John Adams Institute Manchester University Oxford University Rutherford Appleton Laboratory

International CERN FNAL (US) LPNS (FR) TRIUMF (CA)

Project manager : K.Peach (JAI, Oxford university) UK based : Birmingham University Brunel University Cockcroft Institute Daresbury Laboratory Gray Cancer Institute Imperial College London John Adams Institute Manchester University Oxford University Rutherford Appleton Laboratory

International CERN FNAL (US) LPNS (FR) TRIUMF (CA)

• 3.5 years project (Apr. 2007~) with total funds £6.9m from STFC/EPSRC Basic Technology Fund (UK government)

CONFORM: project overview

J.CobbK. PeachS.SheehyT.WitteT.Yokoi

J.CobbK.PeachS.SheehyH.WitteT.Yokoi

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

Scaling FFAG to NS-FFAG

B

B0

1 kxr0

k(k 1)

2!

xr0

2

...

In PAMELA, each multipole fielIn PAMELA, each multipole field up to decapole can be tuned id up to decapole can be tuned individually.ndividually. Flexible tunability of operaFlexible tunability of operating pointting point..

All FFAGs so far built are designAll FFAGs so far built are designed to form scaling magnetic field ed to form scaling magnetic field Hard tHard to change operating point after o change operating point after construction construction

B

B0

r

r0

k

B

B0

r

r0

k

KEK 150MeV FFAG

““Separated function FFAG”Separated function FFAG”

In fixed field accelerator (FFAG, cyclotron)…..In fixed field accelerator (FFAG, cyclotron)…..

Easiness of control Easiness of control Hardness of commissioning and tuning Hardness of commissioning and tuning

In fixed field accelerator (FFAG, cyclotron)…..In fixed field accelerator (FFAG, cyclotron)…..

Ease of control Ease of control Difficulty of commissioning and tuning Difficulty of commissioning and tuning

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

PAMELA:Particle Accelerator for MEdicaL Appl

ications • Advantage of particle therapy ( X-ray)

(1) better dose concentration

(2) better biological effectiveness

photon proton

Spot scanning

From PSI website

• Spot scanning with proton and carbon beam is aimed to realize in PAMELA (better conformal dose field).

• PAMELA : design study of particle therapy facility using NS-FFAG Prototype of versatile FFAG (ex ADSR)

• Advantage of NS-FFAG as particle therapy accelerator

(1) High intensity(synchrotron)

(2) Flexible machine operation (cyclotron)

IMPT (Intensity Modulated Particle therapy) requires high repetition rate time

Inte

gra

ted cu

rrent

FFAG

Step size controls dose

“Digital IM”

Beam intensity is modulated depth-wise

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

PAMELA: ring overview Ring #1 (p, c) Ring #2 (c)

Energy 30~250MeV (p)

8~68MeV/u (c)

68~400MeV/u

# of Cell 12 12

Diameter 12.5m 18.4m

K-value 38 41

Orbit excursion 18cm 21cm

Rev. freq 1.94~4.62MHz(p)

0.98~2.69MHz(c)

1.92~3.91MHz

Repetition rate 1kHz 1kHz

Magnet Triplet(FDF), SC Triplet(FDF), SC

length 57cm 113cm

aperture 25cm 33cm

Long Drift 1.3m 1.2m

Packing factor 0.48 0.65

Inj./Ext 1turn inj/ext

2 LD (each)

1turn inj/ext

2 LD (each

RF Max 8 LD Max 8 LD

Carbon ring

Proron ring

Injector(p): cyclotron

Injector(c): RFQ+LINAC

Long straight section (~1.3m) Small beam excursion (<20cm) Strong field (max 4T) SC magnet

High repetition rate (~1kHz) is a big challenge

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

Beam dynamics

Tune stablization was achieved (∆H<0.1, ∆H<0.05) no need to worry about resonance crossing

2008 PPR

2009

FF

FF

DD

B/B0=(r/r0)k

RD/F(B·l)D/ (B·l)F

Tune can be varied over |∆|<0.25

Relation with field quality and tune drift was well studied

Downward crossing

Upward crossing

Know-how to tailor tune drift was obtained

Dynamic aperture is sufficiently large for proton accelerator (>400 mm mrad)

Understanding of beam dynamics is steadily going forward

Challenges: compatibility of stable tune and operational flexibilityChallenges: compatibility of stable tune and operational flexibility

Horizontal

Vertical

S.Sheehy

Horizontal@injection

Vertical@injection

By S.Sheehy

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

Dipole

Superposition of helical field can form multipole field

Magnet

By H.WitteBy H.Witte

Unknowns …..Unknowns ….. Alignment schemeAlignment scheme Positioning error ….Positioning error …. Local field interference Local field interference

Prototyping is required !! Prototyping is required !!

Unknowns …..Unknowns ….. Mechanical accuracyMechanical accuracy ex positioning error ex positioning error coil windingcoil winding

Prototyping is requiredPrototyping is required

Challenges: Large aperture, short length, strong fieldChallenges: Large aperture, short length, strong field

Dipole Quadrupole

OctapoleSextapole

~23cm

55cm

SC magnet module

Tunability of Individual multipole flexible operation Improved coil configuration (Patent was recently filed)

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

Beam extraction

Hardware R&D of kicker is under Hardware R&D of kicker is under planning (budget request) planning (budget request)

Challenges: Energy variable extraction in fixed field acceleratorChallenges: Energy variable extraction in fixed field accelerator

Vertical fast extraction was adopted in PAMELAVertical fast extraction was adopted in PAMELA

Advantages: (1) weaker kicker field,

(max 0.6kgauss1m for proton )

(2) good matching with FFAG transport

@kicker

CO

@septum

230MeV (Bkicker:0.6kgauss)

∆∆x>2cmx>2cm

FDF FDF

Kicker Septum

Specifications of kicker and septum are within feasible range of engineering for proton.

Kicker field (proton) By H.WitteSeptum field (proton)

Large horizontal beam excursion(ex PAMELA: ~10cm (70MeV230MeV)

Kicker Kicker SeptumSeptum

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

RF system Challenge : high duty cycle, high rate FM, high field gradient

1.1m

2 ferrite core layers

P=VP=V22/(2/(2QL)QL)

Power dissipation is the most serious Power dissipation is the most serious

problem in high repetition operationproblem in high repetition operation

Higher Q is favorableHigher Q is favorable

One solution : Ferrite loaded cavity * tuning bias current is required

Unknowns …..Unknowns …..

Ferrite Properties Ferrite Properties (ex Q-value, high loss effect, (ex Q-value, high loss effect, dynamic loss effect dynamic loss effect Phase error Phase error

Unknowns …..Unknowns …..

Ferrite Properties Ferrite Properties (ex Q-value, high loss effect, (ex Q-value, high loss effect, dynamic loss effect dynamic loss effect Phase error Phase error

Ferrite property measurement has started

* 1KHz repetition rate is 10 times larger than that of existing ferrite rf cavity Ferrite sample

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

(1) Extraction resonance extraction • unique feature of PAMELA. • extraction kicker can be eliminated

Upgrade options ( to carbon ring) For carbon ring, (doable) lattice was proposed.

Downward crossingReal challenges are extraction and acceleration In carbon ring, Z/A=2, max rigidity : 2.6 Real challenges are extraction and acceleration carbon(A/Z=2): hard to bend, accelerate

Resonance pointH

v

∆RD/F :0.017

∆v=0.5

(2) Acceleration multi-bunch acceleration • potentially, more efficient than ferrite cavity • well-matched with resonance extraction

PRISM rf cavity

Wave superposition

Energy Option 1

time

time

Energy Option 2

Option 1: P Nrep2

Option 2: P Nrep

Versatile technologies for high intensity accelerator (ex ADSR)

ESS

t

E “With Flattop”

(1)’ Extraction SC septum • HTS shield for stray field suppression

R0 [m]

Pack

ing

fact

or

Ldrift > 1.2m

Carbon, k=42

Bmax <3.5T

Max bore <35cm

By S. Sheehy

Multi-bunch painting

Direct IM

+=

Active chopper

Hori. field quality

Septum structure

Hori. field

ESS

(3) Intensity modulation(IM) Direct IM • IM@ion source +Active chopper • enhance effective repetition rate

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

R&D plan and resources By end of 2009, Overall ring design is to be finishedBy end of 2009, Overall ring design is to be finished

Budget request for hardware R&DBudget request for hardware R&D

1.1. Magnet : fabrication process, field distribution, Magnet : fabrication process, field distribution, field quality etcfield quality etc

2.2. Kicker : wide-aperture kicker, life time etcKicker : wide-aperture kicker, life time etc

3.3. RF system :ferrite property, dynamic loss effect RF system :ferrite property, dynamic loss effect etcetc. .

Proposal for full size machine (+facility) constructionProposal for full size machine (+facility) construction

( July 2009, PAMELA design review)

Collaboration with MPRG

Collaboration with nuclear engineering and particle physics (proton driver, ADSR etc)

Resource request

test bench + support from CE( rf development )

1 FTE

Resource request

test bench + support from CE( rf development )

1 FTE

11 Dec. 2009@Oxford univ. Particle Physics Project review

Accelerator for cancer therapy By T.Yokoi

Progress from 2008 to 2009

2008 PP project review

(1) Lattice Scheme fixed (∆>0.5**) ** resonance crossing is must

(2) Magnet Scheme : fixed

(3) RF Options: listed up

(4) Extraction Scheme : proposed

(5) Extension to Carbon ring ??

2008 PP project review

(1) Lattice Scheme fixed (∆>0.5**) ** resonance crossing is must

(2) Magnet Scheme : fixed

(3) RF Options: listed up

(4) Extraction Scheme : proposed

(5) Extension to Carbon ring

??

2009 PP project review

(1) Lattice Stable lattice (∆<0.1) **no resonance crossing

tune control scheme : fixed

(2) Magnet R&D work :started, patent :filed

(3) RF Scheme:Fixed, R&D work: started

(4) Extraction Scheme: Fixed R&D work: started

(5) Extension to Carbon ring lattice : propose

(6) Misc Resonance extraction, multi-bunch acceleration, direct intensity modulation etc…

2009 PP project review

(1) Lattice Stable lattice (∆<0.1) **no resonance crossing

tune control scheme : fixed

(2) Magnet R&D work :started, Improved winding (patent:filed)

(3) RF Scheme:fixed, R&D work: started

(4) Extraction Scheme: fixed R&D work: started

(5) Extension to Carbon ring lattice : proposed

(6) Misc Resonance extraction, multi-bunch acceleration, direct intensity modulation etc…

We are creeping forward to the goal !!