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for each nucleon

Optical model. all the interactions between the nucleons are replaced. by an average and central interaction V(r). between the projectile and the target. Why an optical model ?. N body problem. A 1 nucleons. for each nucleon. A 2 nucleons. N=A1+A2 equations to solve. one body problem.

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for each nucleon

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  1. Optical model all the interactions between the nucleons are replaced by an average and central interaction V(r) between the projectile and the target Why an optical model ? N body problem A1 nucleons for each nucleon A2 nucleons N=A1+A2 equations to solve.... one body problem a particle with a mass is in a potential well V(r) which replaces all the interactions between the different nucleons. References: P. E. Hodgson, The nucleon optical potential, Clarendon Press, 1994  :reduced mass of the system G. R. Satchler, Direct nuclear reactions, Oxford University Press, New York, 1983

  2. Optical potential The optical model used to describe the interaction between two nuclei is inspired by the optical phenomena. imaginary V(r) = U(r) + i W(r) real part imaginary part represents the elastic scattering to take into account the others reactions which can occured reflexion of the incident wave simulates the loss of flux due to no elastic collisions absorption of the incident wave V(r) = U(r) + iW(r) + Vso(r) + Vc(r) spin-orbite Coulomb

  3. Phenomenogical optical potential U(r) = Uv f(r) W(r) = Ws g(r) + Wv f(r) Woods- Saxon R: potential radius a: potential diffusness 6He(p,p)6He 150 MeV elastic scattering data: parametrization of Uv, Ws, Wv, av, aWs, aWv, R, Vso d/d (mb/sr) p-nucleus, n-nucleus interaction:parametrization CH89 from Varner et al. nucleus-nucleus interaction: not general parametrization a projectile on a reduced number of target or limitation in energy. parameters adjusted case by case nuclei in their ground sates !!!! cm (deg)

  4. Microscopic optical potential rt rpt Ot p r rp p Target Op Projectile effective nucleon-nucleon force Folding densities : microscopic or macroscopic densities

  5. Link with ABLA The decay width  for evaporation: E = Eimf + Epartner + Q +  - B Now: a real potential is used to describe the transmission probability of particles Kildir et al., PRC 51, 1873 (1995) another possibility to calculate capture: optical potentials (nuclei not in their groundstates) Aleksandra

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