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CAARI 2010-Fort Worth. Stopping, straggling and inner-shell ionization within the shellwise local plasma approximation. C. C. Montanari and J. E. Miraglia. Instituto de Astronomía y Física del Espacio (IAFE). and
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CAARI 2010-Fort Worth Stopping, straggling and inner-shell ionization within the shellwise local plasma approximation C. C. Montanari and J. E. Miraglia Instituto de Astronomía y Física del Espacio (IAFE) and Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina.
Shellwise local plasma approximation (SLPA) r v r • Free electron gas of local density
Shellwise local plasma approximation (SLPA) r v r • Free electron gas of local density • Inputs: densities and binding energies, shell to shell
Shellwise local plasma approximation (SLPA) r v r • Free electron gas of local density • Inputs: densities and binding energies, shell to shell • Dielectric response for each nl-shell, independent shell approx.
Shellwise local plasma approximation (SLPA) r v r • Free electron gas of local density • Inputs: densities and binding energies, shell to shell • Dielectric response for each nl-shell, independent shell approx. Perturbative limit • Validity limits ZP < ZT intermediate to high impact energies,
Shellwise local plasma approximation Dielectric response function Lindhard (1954), e-e correlation to all orders ZP to first order Levine & Louie (1982), energy gap Enl , shell to shell response, satisfies f-sum rule
Calculation • Bound nl-shells j=0, ionization cross section j=1, stopping cross section (SCS); j=2, square straggling(W2) • total
SLPA Results • Stopping • Energy loss Straggling • Ionization of inner shells
Relativistic atoms • Wave functions and binding energies Dirac equation • GRASP, HULLAC
0 EF 4f 7/2 -3.11 4f 5/2 -3.25 -4.13 5s 4d 5/2 -11.8 -12.5 4d 3/2 Au
0 EF 4f 7/2 -3.11 4f 5/2 -3.25 -4.13 5s 4d 5/2 -11.8 -12.5 4d 3/2 Au
SLPA • Independent shell approximation • Screening among electrons-correlation • Same shell? Binding energy? • Incertainty in energy
Au 0 EF -3.17 4f -4.13 5s 4d -12.1
Energy loss straggling of protons in very heavy atoms ( 73< Z <84 )
Inner-shell ionization of in Relativistic atoms • GRASP, HULLAC
Concluding remarks SLPA: • Ab-initio calculation (bound electrons) • Independent shell approximation • includes electronic correlation • Input just densities n(r) and binding energies good for DFT and QCh • Fast calculation (PC), the same for 4f, 3d o 2p Limits • Perturbative first order in ZP • Independent shells vs screening among shells • Locality Future • Complex elements, molecules, clusters • Non perturbative calculation • Semilocal approximation • Screening among different FEG
Acknowledgements • Darío Mitnik • Claudio Archubi • Nestor Arista • Juan Eckardt • Moni Behar • Lokesh Tribed • Helmut Paul Instituto de Astronomía y Física del Espacio, Buenos Aires, Argentina Insttuto Balseiro and Centro Atómico Bariloche, Argentina Universidad Federal de Rio Grande do Sul, Porto Alegre, Brazil Tata Institute of Fundamental Research, Mumbai, India
Buenos Aires, Argentina Thank you!
CAARI 2010-Fort Worth Stopping, straggling and inner-shell ionization within the shellwise local plasma approximation C. C. Montanari and J. E. Miraglia Instituto de Astronomía y Física del Espacio (IAFE) and Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina.
-1.15 4f 7/2 -1.23 4f 5/2 0 W 5p 3/2 -1.35 -1.66 5p 1/2 5s -2.77
Resumé Advantages of the SLPA: 1- e-e correlation to all order 2- Just the electron densities & binding energies. Do not need the continuum. Good for DFT used in QCh. 3- Cartessian coordinates. Not needed central potential 4- Projectile classical trajectory selfconsistent (e impact) Disadvantages 1- First order in the projectile charge 2- It is local 3- It is a model. No perturbative series to follow
Future Developmens 1- Heavy atoms f-shell , molecules & clusters 2- Atom-atom antiscreening (= collision of two FEG) 3- Improve the Local hypothesis by extending to momentum space. Intense activity in QCh