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arXiv · 1302.4237

Shallow and diffuse spin-orbit potential for proton elastic scattering from neutron-rich helium isotopes at 71 MeV/nucleon

S. Sakaguchi·T. Uesaka·N. Aoi·Y. Ichikawa·K. Itoh·M. Itoh·T. Kawabata·T. Kawahara·Y. Kondo·H. Kuboki·T. Nakamura·T. Nakao·Y. Nakayama·H. Sakai·Y. Sasamoto·K. Sekiguchi·T. Shimamura·Y. Shimizu·T. Wakui
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Abstract

Vector analyzing powers for proton elastic scattering from 8He at 71 MeV/nucleon have been measured using a solid polarized proton target operated in a low magnetic field of 0.1 T. The spin-orbit potential obtained from a phenomenological optical model analysis is found to be significantly shallower and more diffuse than the global systematics of stable nuclei, which is an indication that the spin-orbit potential is modified for scattering involving neutron-rich nuclei. A close similarity between the matter radius and the root-mean-square radius of the spin-orbit potential is also identified.

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S. Sakaguchi, T. Uesaka, N. Aoi, Y. Ichikawa, K. Itoh, M. Itoh, T. Kawabata, T. Kawahara, Y. Kondo, H. Kuboki, T. Nakamura, T. Nakao, Y. Nakayama, H. Sakai, Y. Sasamoto, K. Sekiguchi, T. Shimamura, Y. Shimizu, T. Wakui. 2013-02-18. Shallow and diffuse spin-orbit potential for proton elastic scattering from neutron-rich helium isotopes at 71 MeV/nucleon. https://doi.org/10.1103/physrevc.87.021601

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