Swelling of doubly magic $^{48}$Ca core in Ca isotopes beyond $N=28

• Main Authors: Tanaka, M, Takechi, M, Homma, A, Fukuda, M, Nishimura, D, Suzuki, T, Tanaka, Y, Moriguchi, T, Ahn, D. S, Aimaganbetov, A, Amano, M, Arakawa, H, Bagchi, S, Behr, K. -H, Burtebayev, N, Chikaato, K, Du, H, Ebata, S, Fujii, T, Fukuda, N, Geissel, H, Hori, T, Horiuchi, W, Hoshino, S, Igosawa, R, Ikeda, A, Inabe, N, Inomata, K, Itahashi, K, Izumikawa, T, Kamioka, D, Kanda, N, Kato, I, Kenzhina, I, Korkulu, Z, Kuk, Y, Kusaka, K, Matsuta, K, Mihara, M, Miyata, E, Nagae, D, Nakamura, S, Nassurlla, M, Nishimuro, K, Nishizuka, K, Ohnishi, K, Ohtake, M, Ohtsubo, T, Omika, S, Ong, H. J, Ozawa, A, Prochazka, A, Sakurai, H, Scheidenberger, C, Shimizu, Y, Sugihara, T, Sumikama, T, Suzuki, H, Suzuki, S, Takeda, H, Tanaka, Y. K, Tanihata, I, Wada, T, Wakayama, K, Yagi, S, Yamaguchi, T, Yanagihara, R, Yanagisawa, Y, Yoshida, K, Zholdybayev, T. K
• Format: Journal Article
• Language: English
• Published: 12-11-2019
• Subjects: Physics - Nuclear Experiment
• DOI: 10.48550/arxiv.1911.05262

Phys. Rev. Lett. 124, 102501 (2020) Interaction cross sections for $^{42\textrm{-}51}$Ca on a carbon target at
280 MeV/nucleon have been measured for the first time. The neutron number
dependence of derived root-mean-square matter radii shows a significant
increase beyond the neutron magic number $N=28$. Furthermore, this enhancement
of matter radii is much larger than that of the previously measured charge
radii, indicating a novel growth in neutron skin thickness. A simple
examination based on the Fermi-type distribution, and the Mean-Field
calculations point out that this anomalous enhancement of the nuclear size
beyond $N=28$ results from an enlargement of the core by a sudden increase in
the surface diffuseness of the neutron density distribution, which implies the
swelling of the bare $^{48}$Ca core in Ca isotopes beyond $N=28$.