Speaker
Description
Key in the establishment of the traditional concepts of nuclear shells, binding-energy studies were also pivotal to the early realization of the demise of the traditional shell closures away from stability [1]. Extensive effort has followed to examine the classical signatures for magicity in exotic nuclei and more than three decades later, the robustness of all major shell closures has been assessed [2]. Along the way, a number of subshells (e.g N = 32 in $^{52}$Ca) have even been shown to exhibit localized magic behaviour [3].
Over the past year, the online Penning-trap mass spectrometer ISOLTRAP [4,5] has dedicated most of its experimental effort to the study of two topical regions for the study of the shell-evolution phenomenon. On the one hand, extending the study of the N = 32 sub-shell closure from the cadmium (Z =20) to the scandium (Z =21) chain was attempted. On the other hand, a mass-measurement campaign was dedicated to the study of neutron-deficient indium isotopes in the vicinity of the doubly-magic $^{100}$Sn. This campaign performed at extreme of the nuclear landscape was successful to measure $^{99-101}$In and allows the study of the Z=N=50 shell closure in close proximity with the proton drip-line. This contribution will present highlights from both measurement campaigns.
[1] C. Thibault et al., Phys. Rev. C 12, 644 (1975).
[2] O. Sorlin et al., Prog. Part. Nucl. Phys. 61, 2 602-673 (2008).
[3] F. Wienholtz et al., Nature 498, 346–349 (2013).
[4] M. Mukherjee et al., Eur. Phys. J. A 35, 1-29 (2008).
[5] R. Wolf, F. Wienholtz et al., Int. J. Mass. Spectrom. 349-350, 123-133 (2013).
