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arXiv · 1104.5431

Complete electric dipole response and the neutron skin in 208Pb

A. Tamii·I. Poltoratska·P. von Neumann-Cosel·Y. Fujita·T. Adachi·C. A. Bertulani·J. Carter·M. Dozono·H. Fujita·K. Fujita·K. Hatanaka·A. M. Heilmann·D. Ishikawa·M. Itoh·H. J. Ong·T. Kawabata·Y. Kalmykov·E. Litvinova·H. Matsubara·K. Nakanishi·R. Neveling·H. Okamura·B. Özel-Tashenov·V. Yu. Ponomarev·A. Richter·B. Rubio·H. Sakaguchi·Y. Sakemi·Y. Sasamoto·Y. Shimbara·Y. Shimizu·F. D. Smit·T. Suzuki·Y. Tameshige·J. Wambach·R. Yamada·M. Yosoi·J. Zenihiro
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Abstract

A benchmark experiment on 208Pb shows that polarized proton inelastic scattering at very forward angles including 0° is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r_skin = 0.156+0.025-0.021 fm in 208Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence, relevant to the description of neutron stars.

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A. Tamii, I. Poltoratska, P. von Neumann-Cosel, Y. Fujita, T. Adachi, C. A. Bertulani, J. Carter, M. Dozono, H. Fujita, K. Fujita, K. Hatanaka, A. M. Heilmann, D. Ishikawa, M. Itoh, H. J. Ong, T. Kawabata, Y. Kalmykov, E. Litvinova, H. Matsubara, K. Nakanishi, R. Neveling, H. Okamura, B. Özel-Tashenov, V. Yu. Ponomarev, A. Richter, B. Rubio, H. Sakaguchi, Y. Sakemi, Y. Sasamoto, Y. Shimbara, Y. Shimizu, F. D. Smit, T. Suzuki, Y. Tameshige, J. Wambach, R. Yamada, M. Yosoi, J. Zenihiro. 2011-05-30. Complete electric dipole response and the neutron skin in 208Pb. https://doi.org/10.1103/physrevlett.107.062502

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