TMM 21:10:2014 AlessioCaciagli

8/10/2019 TMM 21:10:2014 AlessioCaciagli

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Alessio Cacia li Laser Particle Acceleration www.hzdr.de

HZDR SUMMER STUDENT PROGRAM 2014

A summer well spent playing with big lasers

Utrecht, 21.10.2014



Member of the Helmholtz AssociationPage 2


Introduction

• Question: where has Alessiobeen during August and

September?

• Answer: in Germany!





Introduction

• More precisely… In Dresden!

• Among other things… Famous forDresden (Messen) porcelain

• Artistic opinion of a local:

– Very expensive and…

– …Kitch…





Introduction

• Question: why was Alessio there?

• Answer: for a Summer School! – HZDR Summer Student Program





Introduction

• HZDR is not just a

single building… • Several facilities,

several research fields

– Energy (materials

efficiency, nuclear

reactors…) – Health (cancer

research, brain

diseases…)

– Matter (material

science with ion

beams, accelerator

research…)

My topic:

Laser-Particle Acceleration forCancer therapy application





Particle Acceleration

How to accelerate particles?

...With big rings and long

corridords (and a lot of

money)

GSI Darmstadt

DESY Hamburg

10 MV/m

Particle are subjected to an

electromagnetic field

They acquire kinetic energy

Higher electric

field (lighter

particles)

Higher kinetic

energies


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How to reach higher kinetic energies?

...With even bigger rings and (an insanely awful lot of) more money

LHC at Geneva

(Switzerland).

Radius: 27 km

(Image: CERN)





... Maybe there is another (less bloody expensive) way

10.000.000 MV/m

~ mm

High-power laser hitting an aluminum foil target

(DRACO Laser at HZDR, Dresden)

• 106 times bigger electric

field than in a Linear

Accelerator (LINAC)!

• Acceleration length: ~mm

against ~km





100 TW Laser I = 1020 W/cm2 E0 = 1012 V/m

3 J in 30 fs




Laser Acceleration: Medical application

Why Laser Particle Acceleration?

Laser Driven Proton

Therapy




Why Laser Particle Acceleration?

Advantages overconventional

accelerators:

short acceleration length

Laser Acceleration: Medical application

10.000.000 MV/m

~ mm

Advantages over

conventional cancer

therapy (photontherapy):

Better dose delivery

0 10 20 300

1

Protonen N o r m i e r t e D o s i s

Eindringtiefe in Wasser / cm

Photonen

0 10 20 300

1



Photonen

0 10 20 300

1



Photonen

0 10 20 300

1



Photonen

0 10 20 300

1



Photonen

0 10 20 300

1



Photonen

0 10 20 300

1



Photonen

0 10 20 300

1



Photonen

0 10 20 300

1



Photonen

0 10 20 300

1



Photonen

0 10 20 300

1



Photonen

0 10 20 300

1

(175-190 MeV)Protonen



Photonen

Normal tissue tumor

N o r m a l i z e d d o s e

Depth in water [cm]

Photons

Protons

Protons(175-190 MeV)





Experimental setup at HZDR: DRACO

All this stuff is also done in Dresden…

With DRACO

DResden l Aser aCceleration sOurce

In short words…

A high-power ultra-short-pulses laser





Experimental setup at HZDR: DRACO

• Power: 150 TW (1012 W)

• Peak Intensity: ~1021

W/cm2

• Ultra-short pulses: 4J in ~30 fs

• Pulse train: 10 Hz

Initial short pulse

StretcherOscillator (Ti:Sa)

Compressor Target

Area

Power Amplifiers

High-energy

Ultra-short

pulse





Experimental setup at HZDR:

DRACO

Laser beam

Target

Proton beam

Target alignment!





My contribution: right in the focus of the

Big Laser

• How to know if you are inthe focus?

– Use a camera!

In focus Out of focus





My contribution: right in the focus of the Big Laser

Yes, sometimes

experiment &

computer

models can live

together…

(even though it’s

a forced

convivence)











25 points per minute (was 6…)

Precision requirement: ± 10 μm





Translational Research – Laser Driven Dose Delivery System

Basic research

Clinical practiceLaser driven dose delivery system

Stable & reliable laser protonaccelerator

Precise beam delivery

Real-time dosimetry

Laser / plasmadevelopment

100

depth in water [cm]

• Proton energy

increase

• Sufficiently

monoenergetic

beam r e l a t i v e e f f e c t i v e d

o s e [ % ]

Clinical trials

In vitro- cells

In vivo - animals





Translational Research – Laser Driven Dose Delivery

System

• Direct comparison of laser driven and conventionally accelerated

protons: no difference between both radiation types

• Dose controlled irradiation (over 4000 shots)

• Relative error of less 10% clinical precision standard (3-5%)

within reach





Translational Research – Laser Driven Dose Delivery

System

• Next phase: in vivo irradiations

Main challenge: increase of proton energies to at least 200 MeV

(current is 70 MeV)

Upgrade the laser system

Enhance the effectiveness of acceleration mechanism









Multiple filamentation of freely

propagating 100 TW beam in air

Thank you for your

attention!

Example of freely

propagating Alessio in the lab







Laser Acceleration: TNSA

Acceleration responsible mechanism:

Target-normal sheath acceleration(TNSA)

2. Electron Transport1. Electron Acceleration 3. Electron-proton plasma

expansion

Ion energies: up to 70 MeV




Laser acceleration: Medical application

I = 1020 W/cm2

100 TW Laser I = 1020 W/cm2 E0 = 1012 V/m

Advantage over conventional photon therapy: better dose delivery

0 20 40 60 80 100

Photon irradiation, 9 fields

% Dmax

12C-ion irradiation, 2 portals

0 20 40 60 80 100 % Dmax

Courtesy: O. Jäkel, DKFZ Heidelberg

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TMM 21:10:2014 AlessioCaciagli