Compression-mode resonances in the calcium isotopes and implications for the asymmetry term in nuclear incompressibility

Kevin B. Howard; Umesh Garg; Masatoshi Itoh; Hidetoshi Akimune; Soumya Bagchi; Takanobu Doi; Yuki Fujikawa; Mamoru Fujiwara; Tatsuya Furuno; Muhsin N. Harakeh; Yuto Hijikata; Kento Inaba; Shunya Ishida; Nasser Kalantar-Nayestanaki; Takahiro Kawabata; Shoutaro Kawashima; Kazuya Kitamura; Nobuyuki Kobayashi; Yohei Matsuda; Anna Nakagawa; Shoken Nakamura; Kyoko Nosaka; Shintaro Okamoto; Shinsuke Ota; Sierra Weyhmiller; Zaihong Yang

arXiv · 1911.05267

Compression-mode resonances in the calcium isotopes and implications for the asymmetry term in nuclear incompressibility

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Abstract

Recent data on isoscalar giant monopole resonance (ISGMR) in the calcium isotopes $^{40,44,48}$Ca have suggested that $K_τ$, the asymmetry term in the nuclear incompressibility, has a positive value. A value of $K_τ> 0$ is entirely incompatible with present theoretical frameworks and, if correct, would have far-reaching implications on our understanding of myriad nuclear and astrophysical phenomena. This paper presents results of an independent ISGMR measurement with the $^{40,42,44,48}$Ca($α,α^\prime$) reaction at $E_α= 386$ MeV. These results conclusively discount the possibility of a positive value for $K_τ$, and are consistent with the previously-obtained values for this quantity.

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Kevin B. Howard, Umesh Garg, Masatoshi Itoh, Hidetoshi Akimune, Soumya Bagchi, Takanobu Doi, Yuki Fujikawa, Mamoru Fujiwara, Tatsuya Furuno, Muhsin N. Harakeh, Yuto Hijikata, Kento Inaba, Shunya Ishida, Nasser Kalantar-Nayestanaki, Takahiro Kawabata, Shoutaro Kawashima, Kazuya Kitamura, Nobuyuki Kobayashi, Yohei Matsuda, Anna Nakagawa, Shoken Nakamura, Kyoko Nosaka, Shintaro Okamoto, Shinsuke Ota, Sierra Weyhmiller, Zaihong Yang. 2019-12-20. Compression-mode resonances in the calcium isotopes and implications for the asymmetry term in nuclear incompressibility. https://arxiv.org/abs/1911.05267

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