High-spin states in ${}^{35}\mathrm{S}$

Excited states in ${}^{35}\mathrm{S}$ were investigated by in-beam $\gamma$-ray spectroscopy using the ${}^{26}\mathrm{Mg}({}^{18}\mathrm{O},2\alpha 1n)$ fusion-evaporation reaction. The deexciting $\gamma$ rays were measured with germanium detector arrays along with the measurement of evaporated charged particles in a $4\pi$-segmented Si detector array. The level scheme was extended up to 12.47 MeV. The obtained level structure is compared with the large-scale shell-model calculations. The possibility of isoscalar-pair excited states is discussed for $J=(17/2)$ states with comparison between the experimental and theoretical results.

Figure 1

Background-subtracted $\gamma$-ray coincidence spectra gated on the $2\alpha$-detected case. New transitions observed in the present paper are marked with an asterisk (*).

Figure 2

Proposed level scheme of ${}^{35}\mathrm{S}$ as deduced from the present paper. The spin-parity assignments below the level at 8024 keV were referred from the prior work [26].

Figure 3

ADO ratios of the observed transitions in ${}^{35}\mathrm{S}$ as a function of transition energy. Filled and open circles correspond to assignments for $\mathrm{\Delta }J=1$ and 2, respectively.

Figure 4

Residual Doppler shifts for 732- and 1576-keV transitions. The energy shifts are observed in forward (${47}^{\circ }$), center (${86}^{\circ }$), and backward angles (${147}^{\circ }$), respectively.

Figure 5

Experimental levels compared with calculated levels by large-scale shell-model (LSSM) calculations. The experimental levels for low-lying levels were partly taken from Ref. [26].

Figure 6

Excited levels by experimental data and large-scale shell-model calculations as a function of spin. The positive- and negative-parity states are colored with red and blue, respectively. Parities are not available experimentally when the levels are colored with green. Low-excited levels marked with ${}^{\mathrm{a}}$ in Table 2 are taken from prior work [26].

Figure 7

Comparison between the experimental levels (a: Exp.) and calculated levels (b: LSSM) from the large-scale shell-model calculations relative to $11/2^{+}$. The $2n$ and $pn$ labels represent the calculated levels which allow only two-neutron, and one-proton-one-neutron excitations, respectively. Note that the $17/2^{+}$ states in the LSSM, $2n$ and $pn$ correspond to $17/2_{1,3}^{+}$ from the shell-model calculations.