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arXiv · 1009.4763

Comparison of 120Sn(6He,6He)120Sn and 120Sn(alpha,alpha)120Sn elastic scattering and signatures of the 6He neutron halo in the optical potential

P. Mohr·P. N. de Faria·R. Lichtenthäler·K. C. C. Pires·V. Guimarães·A. Lépine-Szily·D. R. Mendes Junior·A. Arazi·A. Barioni·V. Morcelle·M. C. Morais
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Abstract

Cross sections of $^{120}$Sn($\alpha$,$\alpha$)$^{120}$Sn elastic scattering have been extracted from the $\alpha$ particle beam contamination of a recent $^{120}$Sn($^6$He,$^6$He)$^{120}$Sn experiment. Both reactions are analyzed using systematic double folding potentials in the real part and smoothly varying Woods-Saxon potentials in the imaginary part. The potential extracted from the $^{120}$Sn($^6$He,$^6$He)$^{120}$Sn data may be used as the basis for the construction of a simple global $^6$He optical potential. The comparison of the $^6$He and $\alpha$ data shows that the halo nature of the $^6$He nucleus leads to a clear signature in the reflexion coefficients $\eta_L$: the relevant angular momenta $L$ with $\eta_L \gg 0$ and $\eta_L \ll 1$ are shifted to larger $L$ with a broader distribution. This signature is not present in the $\alpha$ scattering data and can thus be used as a new criterion for the definition of a halo nucleus.

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P. Mohr, P. N. de Faria, R. Lichtenthäler, K. C. C. Pires, V. Guimarães, A. Lépine-Szily, D. R. Mendes Junior, A. Arazi, A. Barioni, V. Morcelle, M. C. Morais. 2010-09-24. Comparison of 120Sn(6He,6He)120Sn and 120Sn(alpha,alpha)120Sn elastic scattering and signatures of the 6He neutron halo in the optical potential. https://doi.org/10.1103/physrevc.82.044606

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