Timeresolved analysis of large amplitude collective motion in metal clusters

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Time-resolved analysis of large amplitude
collective motion inmetal clusters

• Metal clusters close  cousins  of nuclei
• Time resolved  Pump Probe  laser scenarios
• Large amplitude collective motion fission

M. Dinh(Toulouse), P. G. Reinhard (Erlangen), ES
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Time resolved nuclear fission
Fission of a hot nucleus
Measure i) number of emitted neutrons ii)
angular distribution 1 nucleus
 isotropic  2 nuclei  anisotropic 
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Nuclei and metal clusters
Finite Fermi liquid droplets
Constituents Fermions
Neutrons, Protons
Ions, Electrons
? r0,s relevant length/energy scales
? Inter-constituents distance d 1.5-2 r0,s
lB 2p/ kF p r0,s
? Long de Broglie wavelength (ground state)
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Basic theory of nuclei and metal clusters
? Nuclei Nucleon-nucleon interaction
between 1-300 nucleons
? Metal clusters Binding (delocalized
electrons) between 1-10000 atoms
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Model of metal clusters
? Electrons
? Ions
? Explicit ions via pseudo potentials ? Detail of
structure ionic dynamics
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A few time scales
Alkalines (Li, Na, K, Rb, Cs)
Nuclei
? Plasmon (collect. oscill. electrons/ions) ?
Ionic times ? Electron-electron collis. ?
Electron evaporation
Units microscopic time in rs,0/vF -
temperature in eF
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Experimental signals from metal clusters
ds/dE
s ( w )
Ionization potentials Single particle energies
s
Optical response Deformations
Abundances Magic numbers
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Experimental signals from metal clusters
ds/dE
s ( w )
Ionization potentials Single particle energies
s
Optical response Deformations
Abundances Magic numbers
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Optical response deformation effects
Collective motion of electrons / ions
What about fission ?
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Experimental signals from metal clusters
ds/dE
s ( w )
Ionization potentials Single particle energies
s
Optical response Deformations
Abundances Magic numbers
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Experimental signals from metal clusters
ds/dE
Ionization potentials Single particle energies
s
Abundances Magic numbers
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Experimental signals from metal clusters
ds/dE
Ionization potentials Single particle energies
s
Abundances Magic numbers
Photon energy
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Experimental signals from metal clusters
ds/dE
Photoabsorption
Yield
Ionization potentials Single particle energies
Photon energy
s
Abundances Magic numbers
Photon energy
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Experimental signals from metal clusters
ds/dE
Photoabsorption
Yield
Ionization potentials Single particle energies
Photon energy
s
Abundances Magic numbers
Photon energy
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Pump probe for fission principle
Probe
?
2 parameters delay AND frequency w
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Pump probe for fission example
Na14 w ? Na143
Na6 Na82
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Some conclusions and perspectives
? Dynamics of metal clusters Similarities
between metal clusters and nuclei Finite Fermi
liquid droplets, mean-field approaches
Collective modes Optical response as a tool of
analysis of structure and dynamics Pump probe
analysis of fission
? Fast developping field of cluster dynamics ?
Linear and semi linear domain Ex
optical response, photoelectrons spectra ?
Clusters in intense laser field Ex
pump/probe dynamics, Coulomb explosion ?
Relations to other fields Ex
embedded/deposited clusters, biological systems
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