Publisher’s Note:gfactor of theCl44ground state: Probing the reduced

Prolate-Spherical Shape Coexistence atN=28inS44

“…The fit of the electron time distribution (insert of Fig. 1) leads to an half-life of 2.619 (26) µsec, which agrees with the value of 2.3(5) µsec reported in [9]. The 0 + 2 →2 + 1 decay branch, occurs through a strongly converted E2 transition at 36(1) keV, an energy below the experimental threshold of the detection system.…”

“…3, correlations strongly increase from the dou-bly magic 48 Ca (≃2 MeV) down to the exotic deformed 42 Si (≃18 MeV), while the size of the N=28 shell gap gets slightly reduced [23]. This increase of correlations is favored on one hand by neutron quadrupole excitations across the N=28 gap between the f 7/2 and p 3/2 orbits [23], and on the other hand, by the degeneracy of proton s 1/2 and d 3/2 orbits and excitations from the d 5/2 shell [1,[24][25][26]. In both cases, quadrupole correlations are favored by the fact that occupied and valence states are separated by two units of angular momentum.…”

Is the7/21−Isomer State ofS43Spherical?

“…Similar information has been found for exotic nuclei around N ¼ 28 [2]. For the latter nuclei, the set of available theoretical [3,4] and experimental [5][6][7][8][9] data provide a coherent description of the gradual erosion of the N ¼ 28 gap and the onset of deformation from the spherical 48 Ca nucleus towards the neutron-rich and oblate deformed 42 Si nucleus [10]. Midway from these two extremes lie the sulfur isotopes of transitional nature, for which spherical or deformed shape coexistence is expected in 43;44 S mainly based on theoretical interpretations of recent experimental data [11,12].…”

“…Shell model calculations were performed using the ANTOINE code [34,35] and the SDPF-U interaction [36] within the full sdðfpÞ valence space for protons (neutrons) [36] were used for protons and neutrons, respectively, in order to estimate electromagnetic properties. The present theoretical approach using the same interaction has already been shown to provide a fairly good description of the evolution of the nuclear structure from the stability line toward exotic neutron-rich nuclei at N ¼ 27, 28, and 29 [9][10][11][12]14,15,36,37]. The calculated level scheme for 43 S, restricted to states of interest here, is shown in Fig.…”

Single-particle structure of silicon isotopes approachingSi42

“…We use β CM = 50 for all 1p-1h calculations in this work. Reduced transition probabilities for E2 transitions are calculated using effective charges of e p = 1.35, e n = 0.35 [7], while for M 1 transitions, we use g s = 0.75g free s , g π = 1.1, g ν = 0.1 [25]. As described in [26], the cross section for knockout from the initial state i in the A-body system -typically the ground state -to the final state f in the A − 1-body system separates into a spectroscopic factor C 2 S and a single-particle cross section σ sp α :…”