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The reaction of a pulsed 18O beam on a 164Dy target was studied in the first experiment with the NuBall array at the IPN Orsay, France. Excited state half-lives were measured using the fast timing method with 20 LaBr3(Ce) detectors. The timing characteristics of the fully digital acquisition system is briefly discussed. A value for the previously unknown half-life of the first excited 4+ state in 178W is presented. [ABSTRACT FROM AUTHOR]

We present information on the excited states in the prolate-deformed, neutron-rich nuclei 165;167Tb100;102. The nuclei of interest were synthesised following in-flight fission of a 345 MeV per nucleon 238U primary beam on a 2 mm 9Be target at the Radioactive Ion-Beam Factory (RIBF), RIKEN, Japan. The exotic nuclei were separated and identified event-by-event using the BigRIPS separator, with discrete energy gamma-ray decays from isomeric states with half-lives in the Vs regime measured using the EURICA gamma-ray spectrometer. Metastable-state decays are identified in 165Tb and 167Tb and interpreted as arising from hindered E1 decay from the 7-/2[523] single quasi-proton Nilsson configuration to rotational states built on the 3-/2[411] single quasi-proton ground state. These data correspond to the first spectroscopic information in the heaviest, odd-A terbium isotopes reported to date and provide information on proton Nilsson configurations which reside close to the Fermi surface as the 170Dy doubly-midshell nucleus is approached. [ABSTRACT FROM AUTHOR]

A fast-timing experiment was performed at the Argonne National Laboratory in December 2015 and January 2016, measuring decay radiation of fission products from a 252Cf fission source. Details of the set-up, integration with Digital Gammasphere, and the data acquisition system are presented. The timing performance of the set-up, capable of measuring lifetimes from the nanosecond region down to tens of picoseconds, is discussed. First preliminary results from the fast-timing analysis of the fission fragment data are presented. [ABSTRACT FROM AUTHOR]

The UK NuStAR project is the largest nuclear physics project presently funded by the Science Technology Facilities Council (STFC) in UK. The aim of the project is to design, construct and deliver detectors and subdetector systems for FAIR. The main project deliverables are a DESPEC multidetector array for fast timing measurements, a HISPEC ToF detector for mass measurements after the secondary target, and the Si tracker for precise vertex determination in R3B experiments with liquid hydrogen target. [ABSTRACT FROM AUTHOR]

Deep-inelastic collisions of a 208Pb beam on a 208Pb target were performed using the ATLAS accelerator at Argonne National Laboratory. Prompt and delayed -rays from the reaction products were detected using the GAMMASPHERE detector array. The cross-coincidence method was used to identify transitions in 207Tl, by gating on -rays from its bettercharacterised reaction partner 209Bi. A number of new transitions were found in 207Tl. [ABSTRACT FROM AUTHOR]

We have investigated nuclear fragmentation reactions of a relativistic 208Pb beam.Ten isomeric states for nuclei with A = 142-152 and Z = 62-67 were observed. Measured isomeric ratios were compared, together with values from other experiments, with prediction of theoretical models. The discrepancies between the experimental and theoretical values were discussed in terms of transitions by-passing the isomer that are not included in the models. [ABSTRACT FROM AUTHOR]

Electromagnetic transition rates have been measured for decays from the ground state band in the transitional nucleus 100Pd using the Recoil Distance Doppler Shift Method in inverse kinematics via the 24Mg(80Se,4n) 100Pd reaction at a beam energy of 268 MeV. The nuclei produced were stopped using a Cu foil and data were recorded for 10 different target-stopper distances. The gamma-rays emitted were measured using the SPEEDY germanium detector array at WNSL Yale University and the target-to-stopper distances were determined and kept constant using the New Yale Plunger Device. The preliminary results of this study are presented. [ABSTRACT FROM AUTHOR]

Decays of neutron-rich A ~ 190 nuclei have been studied following projectile fragmentation of a 208Pb beam on a 9Be target at the GSI Fragment Separator. Gamma-ray decays from previously reported isomeric states in 188Ta, 190W and 192,193Re were used as internal calibrations for the particle identification analysis, together with the identification of previously unreported isomeric decays in 189Ta and 191W. The current work also identifies β-delayed γ rays following the decay of 188Ta to 188W for the first time. [ABSTRACT FROM AUTHOR]

Gamma rays from the decay of an isomer in 190W116 have been observed following projectile fragmentation of a 1 GeV per nucleon 208Pb beam. An earlier experiment indicated decay from a (10-) isomer to the ground state rotational band. Improved statistics have enabled gamma coincidence and time-difference measurements to be made which alter the previous interpretation. Blocked BCS calculations have also been used together with reduced hindrance factors to indicate possible values of spin-parity for the isomer. [ABSTRACT FROM AUTHOR]

The nuclear structure of neutron-rich N > 126 nuclei has been investigated following their production via relativistic projectile fragmentation of a E/A = 1 GeV 238U beam on a Be target. The preliminary analysis indicates the presence of previously unreported isomeric states in the N = 128 isotones 208Hg and 209Tl. [ABSTRACT FROM AUTHOR]

Relativistic projectile fragmentation of a 208Pb primary beam has been used to produce neutron-rich nuclei with proton-holes relative to the Z = 82 shell closure, i.e., "south" of Pb. β-delayed γ-ray spectroscopy allows to investigate the structural properties of such nuclei with A ~ 195 → 205. The current work presents transitions de-exciting excited states in 204Au, which are the first spectroscopic information on this N = 125 isotone. [ABSTRACT FROM AUTHOR]

Preliminary results from the first experiment of the Stopped Beam RISING campaign are presented. The relativistic projectile fragmentation of a 750 MeV/u beam of 107Ag populated isomeric states in very neutron deficient nuclei at the proton dripline around mass 80-90. Nuclei were unambiguously identified using the FRagment Separator (FRS) and its ancillary detectors located at GSI. The ions produced were slowed down from relativistic energies by means of an Al degrader and implanted in the centre of the high-efficiency Stopped RISING array. This allowed the identification of new excited states in the N = Z = 43 nucleus, 86Tc, populated following the de-excitation of a microsecond isomer. Preliminary results of this analysis, as well as previously unobserved isomeric states in 87,88Tc, are reported. [ABSTRACT FROM AUTHOR]

The first results from a series of experiments focused on the study of the internal structure of nuclei at the extremes of N:Z ratio using isomer spectroscopy are reported. These experiments represent the first of the Stopped Beam section of the Rare Isotopes Investigations at GSI (RIS-ING) project. Exotic nuclei were synthesized using relativistic projectile fragmentation of ∼ 500 → 1000 MeV/u beams of 107Ag, 208Pb, 136Xe and 58Ni, or fission of 750 MeV/u 238U provided by the SIS synchrotron at GSI. A detailed description of the RISING stopped beam set up is given, together with a report of the performance of the associated gamma-ray spectrometer array. Selected results of the first experimental campaign are presented together with a discussion on the use of isomeric spectroscopy to study GeV range nuclear fragmentation. Details on future research plans of this collaboration are also outlined. [ABSTRACT FROM AUTHOR]

Identification of near-yrast states in the β-stable nucleus 91Zr51 has been carried out using the fusion evaporation reaction, 82Se(13C,4n)91Zr at an incident beam energy of 50 MeV. States above the reported τ = 6 µs, Iπ = 21/2+ isomeric level at Ex = 3167 keV have been identified for the first time in this work, a tentative decay scheme of near-yrast states to excitation energies in excess of 10 MeV has been constructed. These states are of relevance to shell model structures formed via limited valence-space configurations in this semi-magic N = 51 nucleus. [ABSTRACT FROM AUTHOR]

Two separate experiments using the Differential Decay Curve Method have been performed to extract mean lifetimes of excited states in 106Cd. The medium-spin states of interest were populated by the 98Mo(12C, 4n) 106Cd reaction performed at the Wright Nuclear Structure Lab., Yale University. From this experiment, two isomeric state mean lifetimes have been deduced. The low-lying states were populated by the 96Mo(13C, 3n)106Cd reaction performed at the Institut für Kernphysik, Universität zu Köln. The mean lifetime of the Iπ = 2+1 state was deduced, tentatively, as 16.4(9) ps. This value differs from the previously accepted literature value from Coulomb excitation of 10.43(9) ps. [ABSTRACT FROM AUTHOR]

Relativistic fragmentation of 208Pb has been used to produce excited states in neutron-rich nuclei with N ≈ 126. Spectroscopic information for a range of nuclei has been obtained through observing delayed γ-ray emissions from isomeric states. Preliminary results for 203,204Pt nuclei are presented. For the first time, excited states have been observed in 203Pt and 204Pt. The yrast structure of 204Pt up to spin-parity, Iπ = (10+) has been tentatively inferred from the internal decay of two isomeric states. [ABSTRACT FROM AUTHOR]

We report on the preliminary results from a study of the decay of the Iπ = 8+ T½ = 2µs isomer in 96Pd performed as part of the Stopped-Beam RISING campaign within the Rare Isotope Investigation at GSI (RISING). The 96Pd ions were produced following the projectile fragmentation of a 750 MeV per nucleon 107Ag primary beam. The reaction products were separated and identified by the in-flight method using the GSI Fragment Separator. The residues of interest were stopped in a perspex stopper surrounded by an array of 15, seven-element germanium Cluster detectors. One of the goals of the current work is to investigate the population of high-spin states produced projectile fragmentation reactions using isomeric ratio measurements to infer information on the angular momentum population distribution. In this short contribution the method and results of determining the isomeric ratio for the Iπ = 8+ microsecond isomer in 96Pd nucleus are presented. [ABSTRACT FROM AUTHOR]

Information on the first excited states in the N = Z = 41 nucleus 82Nb sheds light on the competition of isospin T = 0 and T = 1 states in the A ∼ 80 region. The measurement was performed at the GSI laboratory using fragmentation of a 107Ag primary beam at 750 MeV/u on a 4 g/cm² 9Be target. The fragments were separated and identified unambiguously in the FRagment Separator. Three excited states were observed and the half-life estimate for the isomeric state was extracted. A tentative spin assignment based on the isobaric analogue states systematics in the Tz = 1 nucleus 82Zr, and transition probabilities indicate T = 1 character of the first two excited states, and T = 0 for the isomeric state. [ABSTRACT FROM AUTHOR]

Gamma rays from the decay of an isomer in 190W116 have been observed following projectile fragmentation of a 1 GeV per nucleon 208Pb beam. An earlier experiment indicated decay from a (10-) isomer to the ground state rotational band. Improved statistics have enabled gamma coincidence and time-difference measurements to be made which alter the previous interpretation. Blocked BCS calculations have also been used together with reduced hindrance factors to indicate possible values of spin-parity for the isomer. [ABSTRACT FROM AUTHOR]