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Lifetimes or lifetime limits of a small number of excited states of the sulfur isotopes with mass numbers A=35, 36, 37, and 38 have been measured using the differential recoil-distance method. The isotopes of sulfur were populated in binary grazing reactions initiated by a beam of 36S ions of energy 225 MeV incident on a thin 208Pb target which was mounted in the Cologne plunger apparatus. The combination of the PRISMA magnetic spectrometer and an early implementation of the AGATA γ-ray tracking array was used to detect γ rays in coincidence with projectile-like nuclear species. Lifetime measurements of populated states were measured within the range from about 1 to 100 ps. The number of states for which lifetime measurements or lifetime limits were possible was limited by statistics. For 35S, the lifetime was determined for the first 1/2+ state at 1572 keV; the result is compared with a previous published lifetime value. The lifetime of the 3− state of 36S at 4193 keV was determined and compared with earlier measurements. No previous lifetime information exists for the (6+) state at 6690 keV; a lifetime measurement with large associated error was made in the present work. For 37S, the states for which lifetime limits were established were those at 646 keV with Jπ=3/2− and at 2776 keV with Jπ=11/2−; there are no previously published lifetime values for excited states of 37S. Finally, a lifetime limit was established for the Jπ=(6+) state of 38S at 3675 keV; no lifetime information exists for this state in the literature. Measured lifetime values were compared with the results of state-of-the-art shell-model calculations based on the PSDPF, SDPF-U, and FSU effective interactions. In addition, nuclear magnetic-dipole and electric-quadrupole moments, branching ratios, mixing ratios, and electromagnetic transition rates, where available, have been compared with shell-model values. The current work suffers from poor statistics; nevertheless, lifetime values and limits have been possible, allowing a useful discussion of the ability of state-of-the-art shell-model calculations to reproduce the experimental results.

Reduced transition probabilities have been measured for the neutron-rich Ni73,74,75 nuclei with relativistic Coulomb excitation performed at the RIKEN Nishina Center. For the even-even Ni isotope the determined B(E2;0+→2+) value is compatible within errors with the result of a previous intermediate energy Coulomb excitation experiment, although being somewhat larger. For the odd Ni isotopes B(E2) values have been determined for the first time. In the middle νg9/2 shell nucleus Ni73 three peak candidates have been observed and tentatively assigned to the (5/2+), (13/2+), and (11/2+) excitations. Two peak candidates have been observed in Ni75 and tentatively assigned to the (13/2+) and (11/2+) levels. The measured B(E2) values are in line with the large B(E2) reported in Ni70 and at variance with the small strength measured in Ni72. Excitation energies compare well with the result of large-scale shell-model calculations, while B(E2) values are larger than predicted. This could indicate an increasing contribution of proton excitations across the Z=28 shell closure when approaching Ni78.

8 pags., 2 figs., 2 tabs., Reduced transition probabilities have been measured for the neutron-rich Ni73,74,75 nuclei with relativistic Coulomb excitation performed at the RIKEN Nishina Center. For the even-even Ni isotope the determined B(E2;0+→2+) value is compatible within errors with the result of a previous intermediate energy Coulomb excitation experiment, although being somewhat larger. For the odd Ni isotopes B(E2) values have been determined for the first time. In the middle νg9/2 shell nucleus Ni73 three peak candidates have been observed and tentatively assigned to the (5/2+), (13/2+), and (11/2+) excitations. Two peak candidates have been observed in Ni75 and tentatively assigned to the (13/2+) and (11/2+) levels. The measured B(E2) values are in line with the large B(E2) reported in Ni70 and at variance with the small strength measured in Ni72. Excitation energies compare well with the result of large-scale shell-model calculations, while B(E2) values are larger than predicted. This could indicate an increasing contribution of proton excitations across the Z=28 shell closure when approaching Ni78., The excellent work of the Riken-Nishina Center accelerator staff is acknowledged. We acknowledge the support of Istituto Nazionale di Fisica Nucleare, Italy. We also acknowledge the National Research, Development, and Innovation Fund of Hungary (Project No. K128947); the European Regional Development Fund (Contract No. GINOP-2.3.3-15- 2016-00034); and the National Research, Development, and Innovation Office (NKFIH Contract No. PD124717).

Lifetimes of excited states of the phosphorus isotopes 33 , 34 , 35 , 36 15 P have been measured by using the differential recoil-distance method. The isotopes of phosphorus were populated in binary grazing reactions initiated by a beam of 36 S ions of energy 225 MeV incident on a thin 208 Pb target mounted in the Cologne plunger apparatus. The combination of the PRISMA magnetic spectrometer and an early implementation of the AGATA γ -ray tracking array was used to detect γ rays in coincidence with projectile-like nuclear species. Lifetime measurements of populated states were made within the range from about 1 to 100 ps. The number of states for which lifetime measurements were possible was limited by statistics. For 33 P , lifetime limits were determined for the first 3/2+ and 5/2+ states at 1431 and 1848 keV, respectively; the results are compared with previous published lifetime values. The lifetime of the first 2+ state of 34 P at 429 keV was determined and compared with earlier measurements. For 35 P , the states for which lifetimes, or lifetime limits, were determined were those at 2386, 3860, 4101, and 4493 keV, with Jπ values of 3/2+, 5/2+, 7/2− 1 , and 7/2− 2 , respectively. There have been no previous published lifetimes for states in this nucleus. A lifetime was measured for the stretched π ( 1 f 7 / 2 ) ⊗ ν ( 1 f 7 / 2 ) J π = ( 7 + ) state of 36 P at 5212 keV and a lifetime limit was established for the stretched π ( 1 d 3 / 2 ) ⊗ ν ( 1 f 7 / 2 ) J π = ( 5 − ) state at 2030 keV. There are no previously published lifetimes for states of 36 P . Measured lifetime values were compared with the results of state-of-the-art shell-model calculations based on the PSDPF effective interaction. In addition, measured branching ratios, published mixing ratios, and electromagnetic transition rates, where available, have been compared with shell-model values. In general, there is good agreement between experiment and the shell model; however there is evidence that the shell-model values of the M1 transition rates for the 3/2+1→ 1 / 2 + (ground state) and 5/2+1→ 3 / 2 + 1 transitions in 33 P underestimate the experimental values by a factor between 5 and 10. In 35 P there are some disagreements between experimental and shell-model values of branching ratios for the first and second excited 7/2− states. In particular, there is a serious disagreement for the decay characteristics of the second 7/2− state at 4493 keV, for which the shell-model counterpart lies at 4754 keV. In this case, the shell-model competing electromagnetic decay branches are dominated by E1 and M1 transitions.

The neutron-rich nucleus \nucleus{200}{Pt} is investigated via in-beam \gamma-ray spectroscopy in order to study the shape evolution in the neutron-rich platinum isotopes towards the N = 126 shell closure. The two-neutron transfer reaction \nucleus{198}{Pt}(\nucleus{82}{Se}, \nucleus{80}{Se})\nucleus{200}{Pt} is used to populate excited states of \nucleus{200}{Pt}. The Advanced Gamma Ray Tracking Array (AGATA) demonstrator coupled with the PRISMA spectrometer detects \gamma rays coincident with the \nucleus{80}{Se} recoils, the binary partner of \nucleus{200}{Pt}. The binary partner method is applied to extract the \gamma-ray transitions and build the level scheme of \nucleus{200}{Pt}. The level at 1884\,keV reported by Yates et. al [Phys. Rev. C 37, 1889] was confirmed to be at 1882.1\,keV and assigned as the (6^+_1) state. An additional \gamma ray was found and it presumably de-excites the (8^+_1) state. The results are compared with state-of-the-art beyond mean-field calculations, performed for the even-even \nucleus{190-204}{Pt} isotopes, revealing that \nucleus{200}{Pt} marks the transition from the \gamma-unstable behaviour of lighter Pt nuclei towards a more spherical one when approaching the N=126 shell closure.

WOS: 000326096300003 Lifetimes of the low-lying (11/2(-)) states in Co-63,Co-65 have been measured employing the recoil distance doppler shift method (RDDS) with the AGATA gamma-ray array and the PRISMA mass spectrometer. These nuclei were populated via a multinucleon transfer reaction by bombarding a U-238 target with a beam of Ni-64. The experimental B(E2) reduced transition probabilities for Co-63,Co-65 are well reproduced by large-scale shell-model calculations that predict a constant trend of the B(E2) values up to the N = 40 Co-67 isotope. German BMBF [06 DA 9040 I]; Spanish MINECO [AIC-D-2011-0746, FPA2011-29854]; Generalitat Valenciana (Spain) [PROMETEO/2010/101]; Polish MNiSW [DPN/N190/AGATA/2009]; Science and Technology Facilities Council [ST/I506010/1, ST/F004176/1, ST/I504932/1, ST/J000051/1] The authors want to thank the partial funding of this project by the German BMBF under Contract No. 06 DA 9040 I, the Spanish MINECO under Grants No. AIC-D-2011-0746 and No. FPA2011-29854, the Generalitat Valenciana (Spain) under Grant No. PROMETEO/2010/101, and the Polish MNiSW under Grant No. DPN/N190/AGATA/2009.