Paul McKennaRoyal Society of Edinburgh

Research Fellow

A review of high-intensity laser-driven ion acceleration and induced nuclear phenomena

LEIF Meeting, June 2003

Introduction

Accelerating gradient ~TV/m

Laser-driven proton acceleration

Proton energy (MeV)

0 5 10 15 20 25 30 35 40 45 50 55

Nu

mb

er o

f p

roto

ns

(/M

eV)

106

107

108

109

1010

1011

1012

1013

FrontBack

CPA pulse

Target

CCD camera

Protons

0.1m

m0.

1mm

0.25

mm

0.25

mm

0.5m

m0.

5mm

1.0m

m1.

0mm

BACK

Cu activation

stack

FrontBack

Front

Proton acceleration on Vulcan petawatt

Proton beam quality measurements

Normalised emittance N < 0.5 mm mrad at 40 MeV(c.f. CERN Linac2, protons ~50 MeV: N ~1.7 mm mrad)

Film Cu filters

10 m structure 50 m Au

45 mm

~28 MeV

~35 MeV

1 cm

1 cm

Structure after substracting the general intensity rise in the middle

Source size:~40 m for 40 MeV; :~150 m for 4 MeV

Positron Emission Tomography (PET)

14N + p 11C + 4He 11C 20 mins

13C + p 13N + n 13N 10 mins

15N + p 15O + n 15O 2 mins

18O + p 18F + n 18F 1.7 hours

Laser driven PET isotope production

Target thickness (m)

0 100 200 300 400 500 600

Rat

io o

f 11

C p

rodu

ctio

n: fr

ont /

bac

k0

5

10

15

20

AlMylarAu

Laser driven PET isotope production

11B(p,n)11C

Pulse Energy (J)1 10 100 1000

11C

act

ivity

(B

q) in

duce

d pe

r la

ser

shot

101

102

103

104

105

106

107

108

109

Vulcan: Petawatt

Vulcan: 100TW

L.O.A.

JanUSP

Typical patient dose for P.E.T.

18O(p,n)18F

Automated FDG Synthesis

1. 18F ions are trapped on a cartridge and enriched water [O18]H2O is recovered

2. 18F used in labelling reaction

Laser-driven heavy ion acceleration

Heavy ion acceleration measurements

Targetfoil

Pinhole

Thomson parabola spectrometer

Activationmaterial

VULCAN pulse

CR39

Ions Ions

2.5cm 220cm

5cm

References:

Clark et al., Phys.Rev. Lett., 85, 1654 (2000)

Krushelnick et al., IEEE Trans. Plasma Sci., 28,

1184 (2000)

Nuclear activation: Experiment arrangement

Activation samples

Resistively heated target

Iodine samples

Laser pulse

Ion-induced reactions: Typical gamma spectrum

860C

Main target: 100m Fe, Activation target: C

Fusion-evaporation reactions observed

Fusion-evaporation reactions:

56Fe + 12C 67Ge + n

56Fe + 12C 66Ge + 2n

56Fe + 12C 66Ga + p + n

56Fe + 12C 65Ga + p + 2n

56Fe + 12C 63Zn + + n

56Fe + 12C 62Zn + + 2n

56Fe + 12C 61Cu + + p + 2n

56Fe + 12C 60Cu + + p + 3n

PACE2 – calculated cross-sections

Typical deduced ion spectrum

Protons:

63Cu(p,n)63Zn

Cold: 16 kBq

860C: 100 Bq

Fe ions:

Emax > 7 MeV/nucleon

N ~ 5 x 1011, C ~ 0.5 C

I ~ MA (~ ps pulse)

Laser-driven photo-nuclear reactions

Nuclear activation: Experiment arrangement

Activation samples

Resistively heated target

Iodine samples

Laser pulse

Photo-induced transmutation

129I is a nuclear waste product

Half-life = 15.7 million years

129I( ,n)128I

128I: Half-life = 25 minutes

KWD Ledingham, P McKenna, J Yang, S Shimizu,

T McCanny, L Robson, R P Singhal

Personnel

General Review:

K.W.D.Ledingham, P.McKenna and R.P.Singhal, Science, 16th May 2003

K Krushelnick, MS Wei,

P Nickelson, S Mangles

RJ Clarke, PA Norreys,

KL Lancaster, S Karsch

J Galy,

J Magill

R Chapman,

K SpohrJ Zweit,

J Gillies

Paterson institutefor Cancer Research

M Zepf

M Roth,

E Brambrink,

M Hegelich