G. Orlandini

Response functions from integral transforms with a Lorentz kernel

Abstract We propose to calculate inelastic response functions from the inversion of their integral transform with a Lorentz kernel. The transform can be obtained using bound-state type methods. Thus one does not need to solve the much more complicated continuum problem with many open channels. Contrary to other integral transforms considered in the literature, the inversion leads to results of excellent accuracy and stability. This is explicitly shown for the longitudinal deuteron response.

The Lorentz integral transform (LIT) method and its applications to perturbation-induced reactions

The LIT method has allowed ab initio calculations of electroweak cross sections in light nuclear systems. This review presents a description of the method from both a general and a more technical point of view, as well as a summary of the results obtained by its application. The remarkable features of the LIT approach, which make it particularly efficient in dealing with a general reaction involving continuum states, are underlined. Emphasis is given on the results obtained for electroweak cross sections of few-nucleon systems. Their implications for the present understanding of microscopic nuclear dynamics are discussed.

Photoabsorption on ^4He with a Realistic Nuclear Force

The 4He total photoabsorption cross section is calculated with the realistic nucleon-nucleon potential Argonne V18 and the three-nucleon force (3NF) Urbana IX. Final state interaction is included rigorously via the Lorentz Integral Transform method. A rather pronounced giant resonance with peak cross sections of 3 (3.2) mb is obtained with (without) 3NF. Above 50 MeV strong 3NF effects, up to 35%, are present. Good agreement with experiment is found close to threshold. A comparison in the giant resonance region is inconclusive, since present data do not show a unique picture.

Photodisintegration of three-body nuclei with realistic 2N and 3N forces

Abstract Total photonuclear absorption cross sections of 3 H and 3 He are studied using realistic NN and NNN forces. Final state interactions are fully included. Two NN potential models, the AV14 and the r-space Bonn-A potentials, are considered. For the NNN forces the Urbana-VIII and Tucson-Melbourne models are employed. We find the cross section to be sensitive to nuclear dynamics. Of particular interest in this work is the effect which NNN forces have on the cross section. The addition of NNN forces not only lowers the peak height but increases the cross section beyond 70 MeV by roughly 15%. Cross sections are computed using the Lorentz integral transform method.

Two body photodisintegration of He-4 with full final state interaction

The cross sections of the processes

Longitudinal response functions of H-3 and He-3

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Improved (e,e') response functions at intermediate momentum transfers: The He-3 case

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Improved transverse (e,e-prime) response function of He-3 at intermediate momentum transfers

gamma,p

Magnetic susceptibility and M1 transitions in208Pb

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A microscopic evaluation of the nuclear dipole polarizability

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