Slide_template_ITU'ppt

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LASER-INDUCED-NUCLEAR BEAM OF PHOTONS, NEUTRONS
AND IONS WITH POTENTIAL APPLICATIONS J. Galy,
D.J. Hamilton, C. Normand
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Advances in laser intensity over the age
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Historical background

• More than 10 years ago (1988), Boyer et al.
  Discussed the possibility of inducing nuclear
  transitions using a laser
• Discussion between K. Ledingham (Glasgow Univ.)
  and J. Magill (ITU) on the possibility of
  inducing 238U(g,f)
• First successful experiment at VULCAN, RAL (UK)
  in 2000, followed by NOVA, LLNL(USA)

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Lasers entering nuclear science ...
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Nuclear Reactions Triggered by Lasers
bbbbbbbbbbbbb
30 TW LOA laser
JETI chamber
PW VULCAN target chamber
UHI10 target chamber at SLIC
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The cascade process of energy transfer from the
laser pulse to the radiations

• Primary processes are due to the action of the
  laser EM field on a plasma
• Fast electrons initiate secondary processes

protons
plasma
plasma fast e- 1010 K
TW laser pulse
ions
target
gamma rays
gt1018 W/cm2
gt1018 W/cm2
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Bremsstrahlung applications

• Multi-MeV electrons are stopped in thick high Z
  material
• They radiate typical bremsstrahlung g rays (few
  10 MeV)

• production of medical isotopes through
  transmutation
• studies of alternative research paths to
  classical reactor-induced reaction for
  transmutation purposes
• measurement of nuclear data
• detection of illicit radioactive material
• diagnostic tools for plasma physic experiments

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Comparison of laser induced fission rates
These rates highlight improvements in the ability
to induce photonuclear reactions as laser
technology and associated electron acceleration
mechanisms continue to improve.
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Laser proton production

• Maximum p energy is a function of Il2
• Emax a(I?2)a
• For Il2 gt 1019
• a 4 or 3 x 10-9 MeV
• a 0.5
• Mendonca, Spencer, 2000

Higher efficiency 10 to 20 achievable (even
50 ) High-intensity, ultra-fast laser pulse
1020 W/cm2, ? 1 µm
Average proton energy is approximately 5 to 10
times smaller.
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Proton Beam Applications

• Fast proton radiography (ns pulses)
• Proton induced fission (p,f) measurement of new
  cross sections on highly radioactive actinides
• Spallation related studies (Mc Kenna et al.)
• Neutron source via (p,xn) reactions (Zagar et
  al.)
• ITU project of H-loaded Pd film to optimize yield
  and energy distribution of emitted protons
• Security related projects e.g.
• FIGARO (Fissile Interrogation using Gamma Rays
  from Oxygen)
• NEUPHO (JRC-IRMM)

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Detection of illicit material using protons
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Alternative way of producing 225Ac for
alpha-immunotherapy ?
2n
p
225Ac could be produced through two paths

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Other laser-driven ion beams ?

• Both radioactive and stable ion beams could be
  studied

40 MeV 16O ions, 120 MeV 35Cl ions, 500 MeV
208Pb ions
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Heavy ion acceleration applications
Comparison of two experimental designs for
production and detection of super-heavy elements.
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Laser induced neutron sources
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Laser Generated Neutron Sources

• Some General Properties
• Compact Table-Top Sources (!)
• Fast Neutrons Broad Spectrum
• Forward Directed Beams
• Pulsed Operation
• Very Short Pulse Durations (!)
• High Repetition Rates
• Useful Source Strengths

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Positron sources and applications

• Positrons sources are used in positron
  annihilation spectroscopy, atomic and molecular
  physics, modeling of astrophysical processes,
  characterization of material,
• Recent calculations based on VULCAN experimental
  electron spectrum have demonstrated a positron
  rate of 1.5x10-2 p/e (previous report in NOVA
  10-4) leading to a rate of 109 positrons/shot

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Positrons (2)

• The laser positron production rate can be
  directly compared to traditional positron sources
• Development of terawatt tabletop lasers with
  high repetition rates would make those positrons
  sources realistic

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Conclusions and perspectives

• Giant pulse single shot and high repetition rate
  tabletop laser have demonstrated their abilities
  to produced beam of electron and ions
• This research field is developing fast with fast
  development of high intensity laser
• Lasers do offer a new approach to studying
  material behavior under neutral and charge
  particle irradiation without resource to reactors
  or accelerators
• Currently laser light can directly accelerate
  electrons to relativistic speeds, and can
  consequently accelerate protons and other ions.
  In near future lasers will be able to accelerate
  protons to relativistic speeds directly
• New table-top radiation sources will become
  available
• We have shown possible applications of laser
  accelerated electrons, protons, gammas, neutrons
• One can expect that these systems can be put to
  use as strong, and possibly compact sources, for
  nuclear applications.

Table-top lasers ? Table-top radiation sources?