Title:
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Antisymmetrisation of few-body models for light nuclei
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Three-body models are well suited to the description of light exotic nuclei, as they provide the correct representation of the asymptotics of Borromean systems. However, the exclusion principle can only be treated approximately, using Pauli blocking techniques. The effectiveness of these methods is tested, by fully antisymmetrising a variety of three-body wave functions. To achieve this, an inter-cluster antisymmetriser is applied to six-body wave functions of 6He, consisting of the three-body models and an intrinsic function for the a-particle core. Monte Carlo integration is employed to calculate various observables for these wave functions, with and without inter-cluster antisymmetrisation. For all of the models tested, the squared norm was found to increase by approximately 40%, while the rms radius was reduced by around 0. 1 fm. Calculations of the wave function densities show that this corresponds to an increase in the interior region of the wave functions, and consequently a reduction in the wave function tails. The antisymmetrised wave functions were applied to two elastic scattering scenarios; 6He + 12C at 38. 3 MeV, analysed using the optical model, and 6He + p at 717 MeV per nucleon, which was treated using Glauber theory. In the first case no significant effect was found, but a measurable difference was seen for the high energy scattering. The changes in the cross sections were consistent with the decrease in rms radius of the antisymmetrised wave functions.
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