Search for halo nucleus in Mg isotopes through the measurements of reaction cross sections towards the vicinity of neutron drip line

¹ Gesellschaft für Schwerionenforschung GSI, 64291 Darmstadt, Germany
² RIKEN, Nishina Center, Wako, Saitama 351-0106, Japan
³ Department of Physics, Niigata University, Niigata 950-2102, Japan
⁴ Department of Physics, Tokyo University of Science, Chiba, 278-8510, Japan
⁵ Department of Physics, Osaka University, Osaka 560-0043, Japan
⁶ Department of Physics, Saitama University, Saitama 338-8570, Japan
⁷ Institute of Physics, University of Tsukuba, Ibaragi, 305-8571, Japan
⁸ Cyclotron and Radioisotope Center, Tohoku University, Aoba-ku, Sendai 980-8578, Japan
⁹ Research Center of Nuclear Physics (RCNP), Osaka University, Ibaraki 567-0047, Japan
¹⁰ Shanghai Institute of Applied Physics, Chinese Academy of Sciences, P. O. Box 800-204, Shanghai 201800, China
¹¹ Department of Physics and Astronomy, Uppsala University, 751-20, Uppsala, Sweden
¹² Faculty of Engineering, Kochi University of Technology Kochi, 782-8502, Japan
¹³ Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
¹⁴ Department of Physics, Kyushu University, Fukuoka 812-8581, Japan
¹⁵ Creative Research Institution (CRIS), Hokkaido University, Sapporo 001-0021, Japan

^a e-mail: m.takechi@gsi.de

Published online: 20 March 2014

Abstract

Reaction cross sections (σ_R) for ^24–38Mg on C targets at the energies of around 240 MeV/nucleon have been measured precisely at RIBF, RIKEN for the purpose of obtaining the crucial information on the changes of nuclear structure in unstable nuclei, especially around the so-called “island of inversion” region. In the island of inversion region, which includes neutron-rich Ne, Na, and Mg isotopes, the vanishing of the N = 20 magic number for neutrons have been discussed along with nuclear deformation. The present result suggest deformation features of Mg isotopes and shows a large cross section of weakly-bound nucleus ³⁷Mg, which could be caused by a neutron halo formation.