학술논문
Border of the Island of Inversion: Unbound states in $^{29}$Ne
Document Type
Working Paper
Author
Holl, M.; Lindberg, S.; Heinz, A.; Kondo, Y.; Nakamura, T.; Tostevin, J. A.; Wang, H.; Nilsson, T.; Achouri, N. L.; Falou, H. Al; Atar, L.; Aumann, T.; Baba, H.; Boretzky, K.; Caesar, C.; Calvet, D.; Chae, H.; Chiga, N.; Corsi, A.; Crawford, H. L.; Delaunay, F.; Delbart, A.; Deshayes, Q.; Fernández, P. Díaz; Dombrádi, Z.; Douma, C. A.; Elekes, 13 Z.; Fallon, P.; Gašparić, I.; Gheller, J. -M.; Gibelin, J.; Gillibert, A.; Harakeh, M. N.; Hirayama, A.; Hoffman, C. R.; Horvat, A.; Horváth, Á.; Hwang, J. W.; Isobe, T.; Kahlbow, J.; Kalantar-Nayestanaki, N.; Kawase, S.; Kim, S.; Kisamori, K.; Kobayashi, T.; Körper, D.; Koyama, S.; Kuti, I.; Lapoux, V.; Marqués, F. M.; Masuoka, S.; Mayer, J.; Miki, K.; Murakami, T.; Najafi, M.; Nakano, K.; Nakatsuka, N.; Obertelli, A.; Santos, F. de Oliveira; Orr, N. A.; Otsu, H.; Ozaki, T.; Panin, V.; Paschalis, S.; Revel, A.; Rossi, D.; Saito, A. T.; Saito, T. Y.; Sasano, M.; Sato, H.; Satou, Y.; Scheit, H.; Schindler, F.; Schrock, P.; Shikata, M.; Shimizu, Y.; Simon, H.; Sohler, D.; Sorlin, O.; Stuhl, L.; Takeuchi, S.; Tanaka, M.; Thoennessen, M.; Törnqvist, H.; Togano, Y.; Tomai, T.; Tscheuschner, J.; Tsubota, J.; Uesaka, T.; Yang, Z.; Yasuda, M.; Yoneda, K.
Source
Subject
Language
Abstract
The nucleus $^{29}$Ne is situated at the border of the island of inversion. Despite significant efforts, no bound low-lying intruder $f_{7/2}$-state, which would place $^{29}$Ne firmly inside the island of inversion, has yet been observed. Here, the first investigation of unbound states of $^{29}$Ne is reported. The states were populated in $^{30}\mathrm{Ne}(p,pn)$ and $^{30}\mathrm{Na}(p,2p)$ reactions at a beam energy of around $230$ MeV/nucleon, and analyzed in terms of their resonance properties, partial cross sections and momentum distributions. The momentum distributions are compared to calculations using the eikonal, direct reaction model, allowing $\ell$-assignments for the observed states. The lowest-lying resonance at an excitation energy of 1.48(4) MeV shows clear signs of a significant $\ell$=3-component, giving first evidence for $f_{7/2}$ single particle strength in $^{29}$Ne. The excitation energies and strengths of the observed states are compared to shell-model calculations using the sdpf-u-mix interaction
Comment: 12 pages, 14 figures, accepted for publication in Physical Review C
Comment: 12 pages, 14 figures, accepted for publication in Physical Review C