A simulation-based study concerning three non-destructive approaches by which water in spent nuclear fuel assemblies might be quantified with neutrons is described. Three fuel types have been considered: thirty-six spent Advanced Gas-cooled Reactor (AGR) fuel pins contained in a stainless-steel can; a prototype fast reactor (PFR) spent fuel assembly and a light water reactor (LWR) spent fuel assembly - with the PFR and LWR assemblies containing mixed oxide fuels. The three approaches are investigated with MCNP5 based on neutron interrogation: fast neutron detection of the perturbed fast neutron flux and two approaches based on the 2.223 MeV gamma-ray photon emission resulting from the 1H(n,gamma)2H capture reaction, stimulated with moderated and unmoderated neutrons. For each of these approaches the following perspectives have been considered: neutron transmission, the influence of radiation emitted by the associated spent fuel inventory, and the dependencies on water quantity and location. The moderated gamma-ray assay technique is observed to return the most significant distinction between scenarios with and without water in the fuel assemblies, notwithstanding the need for efficiency response functions to be overlaid on the neutron models as part of the interpretation of the MCNP model results. Water present in all of the spent fuels considered is observed to perturb the incident neutron flux to a degree significant within the simulation uncertainties. The AGR and PFR cases are not undermined by the intrinsic neutron field from the fuel; whereas for the LWR-MOX case, the simulations suggest that this will limit its potential. Successful detection of water quantities down to 10 g is anticipated for AGR, whereas reduced mass sensitivity is forecast for PFR and LWR-MOX, where it is assumed that the water will be more dispersed. Water located in fewer locations is observed to be harder to discern, suggesting that small, localised quantities of water could pose a challenge for these techniques.

Proof-of-principle inelastic proton scattering measurements have been performed at NCSR “Demokritos”. Excited states in 64Zn and 92Mo were populated using the (p,p'γ) reaction with E(p) = 7 MeV. The reaction γ rays were detected using four HPGe detectors at eight separate angles, with respect to the beam-axis. From Doppler-shift attenuation of the ∞ rays, lifetimes for eight excited states in 64Zn and for the Iπ = 2^+_2 and 2^+_3 states in 92Mo were deduced. The lifetimes measured in 92Mo are in good agreement with adopted values whereas the lifetimes measured in 64Zn are typically longer than the literature values. Development of the experimental set-up and potential novel physics cases where this reaction could be used are briefly discussed.

Cross section for 241Am(n,2n)240Am reaction has been measured at the VdG Tandem accelerator of NCSR “Demokritos", at neutron beam energy 10.4 MeV, using the activation technique. The high purity and high radioactivity (5GBq) Am target has been constructed at IRMM, Belgium and consisted of 40 mg Am in the form of AmO2 pressed into pellet with Al2O3 and encapsulated into Al container. The absolute flux of the beam was obtained with respect to the 27Al(n,α)24Na reference reaction. The induced gamma-ray activity of 240Am and 24Na was measured with high resolution HPGe detectors.

As part of the RCUK–India civil nuclear research collaboration, British and Indian researchers have assessed the merits and disadvantages of, and potential for, open-cycle thorium–uranium-fuelled (Th–U-fuelled) nuclear energy systems. The research centred on fuel cycle modelling and life-cycle assessment of three Th–U-fuelled nuclear energy systems and compared these to a reference uranium-fuelled nuclear energy system, all operating with open nuclear fuel cycles. The results indicate that thorium-based fuels offer little benefit over conventional uranium-fuelled approaches for open-cycle nuclear energy production. This chapter provides an overview on the project and stresses overarching conclusions.

E. E. Peters,1,* A. E. Stuchbery,2 A. Chakraborty,1,3,† B. P. Crider,3,‡ S. F. Ashley,1,3 A. Kumar,3,1,§ M. T. McEllistrem,3 F. M. Prados-Estévez,1,3 and S. W. Yates1,3,‖ 1Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506-0055, USA 2Department of Nuclear Physics, Research School of Physics and Engineering, The Australian National University, Canberra ACT 2601, Australia 3Department of Physics & Astronomy, University of Kentucky, Lexington, Kentucky 40506-0055, USA

Lifetimes of the excited states in the yrast band of 102Pd have been deter- mined using the Recoil-Distance Doppler Shift experiment at INFN, Labo- ratori Nazionali di Legnaro. Excited states in 102Pd were populated by the 92Zr(13C,3n)102Pd fusion-evaporation reaction. Lifetimes were deduced using the Differential Decay Curve method and the corresponding B(E2) values were compared to the E(5) critical-point symmetry, and also the U(5) and O(6) limits of the Interacting Boson Model-1. It is evident that 102Pd agrees poorly with the predicted E(5) symmetry but has a very good (and somewhat surprising) agreement with the O(6) limit.

Inelastic neutron scattering was used to study the low-lying nuclear structure of $^{132}$Xe. A comprehensive level scheme is presented, as well as new level lifetimes, multipole mixing ratios, branching ratios, and transition probabilities. Comparisons of these data as well as previously measured $E2$ strengths and $g$ factors are made with new shell-model calculations for $^{132,134,136}$Xe to explore the emergence of collectivity in the Xe isotopes with $N$ < 82 near the closed shell.

Received 19 December 2017DOI:https://doi.org/10.1103/PhysRevC.97.029902©2018 American Physical SocietyPhysics Subject Headings (PhySH)Electromagnetic transitionsResearch AreasNuclear structure & decaysElectromagnetic transitionsResearch AreasElectromagnetic transitionsEnergy levelsLow & intermediate energy heavy-ion reactionsNuclear spin & parityNuclear structure & decaysProton emissionShell modelProperties150 ≤ A ≤ 189Nuclear Physics

The operation of nuclear facilities has, fortunately, not led to many accidents with off-site consequences. However, it is well-recognised that should a large release of radioactivity occur, the effects in the surrounding area and population will be significant. These effects can be mitigated by developing emergency preparedness and response plans prior to the operation of the nuclear facility that can be exercised regularly and implemented if an accident occurs. This review paper details the various stages of a nuclear accident and the corresponding aspects of an emergency preparedness plan that are relevant to these stages, both from a UK and international perspective. The paper also details how certain aspects of emergency preparedness have been affected by the accident at Fukushima Dai-ichi and as a point of comparison how emergency management plans were implemented following the accidents at Three Mile Island 2 and Chernobyl. In addition, the UK's economic costing model for nuclear accidents COCO-2, and the UK's Level-3 Probabilistic Safety Assessment code "PACE" are introduced. Finally, the factors that affect the economic impact of a nuclear accident, especially from a UK standpoint, are described. (C) 2017 The Authors. Published by Elsevier B.V. on behalf of Institution of Chemical Engineers.

The low-lying, low-spin levels of Ge-76 were studied with the (n, n'gamma) reaction. Gamma-ray excitation function measurements were performed at incident neutron energies from 1.6 to 3.7 MeV, and gamma-ray angular distributions were measured at neutron energies of 3.0 and 3.5 MeV. From these measurements, level spins, level lifetimes, gamma-ray intensities, and multipole mixing ratios were determined. No evidence for a number of previously placed levels was found. Below 3.3 MeV, many new levels were identified, and the level scheme was re-evaluated. The B(E2) values support low-lying band structure. The 2(+) mixed-symmetry state has been identified for the first time. A comparison of the level characteristics with large-scale shell model calculations yielded excellent agreement.

Nuclear accidents have the potential to lead to significant off-site effects that require actions to minimise the radiological impacts on people. Such countermeasures may include sheltering, evacuation, restrictions on the sale of locally-grown food, and long-term relocation of the population amongst others. Countries with nuclear facilities draw up emergency preparedness plans, and put in place such provisions as distributing instructions and iodine prophylaxis to the local population. Their plans are applied in simulated exercises on a regular basis. The costs associated with emergency preparedness and the safety provisions to reduce the likelihood of an accident, and/or mitigate the consequences, are justified on the basis of the health risks and accident costs averted. There is, of course, only limited actual experience to indicate the likely costs so that much of the costing of accidents is based on calculations. This paper reviews the methodologies used, in particular the approach that has been developed in the UK, to appraise the costs of a hypothetical nuclear accident. Results of analysing a hypothetical nuclear accident at a fictitious reactor site within the United Kingdom are discussed in relation to the accidents at Three Mile Island 2, Chernobyl and Fukushima Dai-ichi. (C) 2017 The Authors. Published by Elsevier B.V. on behalf of Institution of Chemical Engineers.

The quenching of the experimental spectroscopic factor for proton emission from the short-lived d_3/2 isomeric state in ^151mLu was a long-standing problem. In the present work, proton emission from this isomer has been reinvestigated in an experiment at the Accelerator Laboratory of the University of Jyväskylä. The proton-decay energy and half-life of this isomer were measured to be 1295(5) keV and 15.4(8) μs, respectively, in agreement with another recent study. These new experimental data can resolve the discrepancy in the spectroscopic factor calculated using the spherical WKB approximation. Using the R-matrix approach it is found that the proton formation probability indicates no significant hindrance for the proton decay of ^151mLu.

The level structure of Xe-134 was studied with the inelastic neutron scattering reaction followed by gamma-ray detection. A number of level lifetimes were determined for the first time with the Doppler-shift attenuation method and the low-lying excited states were characterized. From this new spectroscopic information, the third excited state, a 0(+) levelwhich had only been observed in a previous inelastic neutron scattering study, was verified. Reduced transition probabilities were calculated; comparisons were drawn with a vibrational description of the nucleus and found lacking. The 3(-) octupole phonon has been confirmed, and the complete negative-parity multiplet resulting from the.(1h(11/2)2d(3/2)) configuration has also been tentatively identified for the first time in the N = 80 isotones.

The excited states of the proton emitter Lu-151 were reinvestigated in a recoil-decay tagging experiment at the Accelerator Laboratory of the University of Jyvaskyla (JYFL). The level scheme built on the ground state of 151Lu was updated with five new y-ray transitions. Large-scale shell model calculations were carried out in the model space consisting of the neutron and proton orbitals 0g(7/2), Id(5/2), Id(3/2), 2s(1/2), and Oh(1/2) with the optimized monopole interaction in order to interpret the experimental level scheme of Lu-151. It is found that the excitation energies of states above the 27/2(-) and 23/2(+) isomeric levels in Lu-151 can be sensitive to excitations from g(7/2) and d(5/2) to single-particle orbitals above N = Z = 64.

We present the results of a structured discussion held in London in July 2014 involving a panel of experts drawn from three communities: specialists on aspects of risk and insurance; lawyers concerned with issues of nuclear law; and safety and environmental regulators. The discussions were held on the basis of participant anonymity. The process emphasised three considerations: conceptions of loss arising from a severe nuclear accident; the specifics of the Fukushima-Daiichi accident and what it means for policy and strategy going forward; and the future of liability regimes. We observe some stoicism from those closest to implementation of policies and procedures associated with nuclear risks, but a lower level of certainty and confidence among those concerned with nuclear energy regulation. (C) 2017 The Authors. Published by Elsevier B.V. on behalf of Institution of Chemical Engineers.

S. Mukhopadhyay,1,2,* B. P. Crider,1 B. A. Brown,3,4 S. F. Ashley,1,2 A. Chakraborty,1,2,† A. Kumar,1,2 M. T. McEllistrem,1 E. E. Peters,2 F. M. Prados-Estévez,1,2 and S. W. Yates1,2 1Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506-0055, USA 2Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506-0055, USA 3National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA 4Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA (Received 25 September 2016; revised manuscript received 4 December 2016; published 25 January 2017)