decay of exotic P and S isotopes with neutron number near 28

Tripathi, V.*; Bhattacharya, S.*; Rubino, E.*; Benetti, C.*; Perello, J. F.*; Tabor, S. L.*; Liddick, S. N.*; Bender, P. C.*; Carpenter, M. P.*; Carroll, J. J.*; et al.

Physical Review C, 106(6), p.064314_1 - 064314_14, 2022/12

https://doi.org/10.1103/PhysRevC.106.064314

no abstracts in English

Compositional and structural analysis of Fukushima-derived particulates using high-resolution X-ray imaging and synchrotron characterisation techniques

Martin, P. G.*; Jones, C. P.*; Cipiccia, S.*; Batey, D. J.*; Hallam, K. R.*; Satou, Yukihiko; Griffiths, I.*; Rau, C.*; Richards, D. A.*; Sueki, Keisuke*; et al.

Scientific Reports (Internet), 10(1), p.1636_1 - 1636_11, 2020/01

https://doi.org/10.1038/s41598-020-58545-y

Provenance of uranium particulate contained within Fukushima Daiichi Nuclear Power Plant Unit 1 ejecta material

Martin, P. G.*; Louvel, M.*; Cipiccia, S.*; Jones, C. P.*; Batey, D. J.*; Hallam, K. R.*; Yang, I. A. X.*; Satou, Yukihiko; Rau, C.*; Mosselmans, J. F. W.*; et al.

Nature Communications (Internet), 10, p.2801_1 - 2801_7, 2019/06

https://doi.org/10.1038/s41467-019-10937-z

Synchrotron radiation (SR) analysis techniques alongside secondary ion mass spectrometry (SIMS) measurements have been made on sub-mm particulate material derived from reactor Unit 1 of the Fukushima Daiichi Nuclear Power Plant (FDNPP). Using these methods, it has been possible to investigate the distribution, state and isotopic composition of micron-scale U particulate contained within the larger Si-based ejecta material. Through combined SR micro-focused X-ray fluorescence (SR-micro-XRF) and absorption contrast SR micro-focused X-ray tomography (SR-micro-XRT), the U particulate was found to be located around the exterior circumference of the highly-porous particle. Synchrotron radiation micro-focused X-ray absorption near edge structure (SR-micro-XANES) analysis of a number of these entrapped particles revealed them to exist within the U(IV) oxidation state, as UO, and identical in structure to reactor fuel. Confirmation that this U was of nuclear origin (U-enriched) was provided through secondary ion mass spectrometry (SIMS) analysis with an isotopic enrichment ratio characteristic of a provenance from reactor Unit 1 at the FDNPP. These results provide clear evidence of the event scenario (that a degree of core fragmentation and release occurred from reactor Unit 1), with such spent fuel ejecta existing; (i) within the stable U(IV) oxidation state; and (ii) contained within a bulk Si-based particle. While this U is unlikely to represent an environmental or health hazard, such assertions would likely change, however, should break-up of the Si-containing bulk particle occur. However, more important to the long-term decommissioning of the reactors (and clean-up) on the FDNPP, is the knowledge that core integrity of reactor Unit 1 was compromised with nuclear material existing outside of the reactors primary containment.

Analysis of external surface irregularities on Fukushima-derived fallout particles

Martin, P. G.*; Satou, Yukihiko; Griffiths, I.*; Richards, D.*; Scott, T.*

Frontiers in Energy Research (Internet), 5, p.25_1 - 25_9, 2017/09

https://doi.org/10.3389/fenrg.2017.00025

Method for the prediction of the effective dose equivalent to the crew of the International Space Station

El-Jaby, S.*; Tomi, L.*; Sihver, L.*; Sato, Tatsuhiko; Richardson, R. B.*; Lewis, B. J.*

Advances in Space Research, 53(5), p.810 - 817, 2014/03

https://doi.org/10.1016/j.asr.2013.12.022

This paper describes a methodology for assessing the pre-mission exposure of space crew aboard the International Space Station (ISS) in terms of an effective dose equivalent. In this approach, the PHITS Monte Carlo code was used to assess the particle transport of galactic cosmic radiation (GCR) and trapped radiation for solar maximum and minimum conditions through an aluminum shield thickness. From these predicted spectra, and using fluence-to-doseconversion factors, a scaling ratio of the effective dose equivalent rate to the ICRU ambient doseequivalent rate at a 10 mm depth was determined. Only contributions from secondary neutrons, protons, and alpha particles were considered in this analysis.

Azimuthal correlations of electrons from heavy-flavor decay with hadrons in and Au+Au collisions at = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.

Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04

https://doi.org/10.1103/PhysRevC.83.044912

Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.

VHTR Deep Burn applications

Richards, M.*; Venneri, F.*; Shimakawa, Satoshi

Proceedings of 16th Pacific Basin Nuclear Conference (PBNC-16) (CD-ROM), 6 Pages, 2008/10

A key feature of the Very High Temperature Reactor (VHTR) is its use of ceramic, coated-particle fuel that can be irradiated at very high temperatures to very high burnup. In this paper we describe applications for deep-burn VHTRS (DB-VHTRs) using Pu, transuranic (TRU), and mixed oxide (MOX) fuels. One application is efficient and economic disposition of surplus weapons-grade Pu (WPu). A DB-VHTR using WPu fuel can consume about 65% of the WPu and about 90% of the Pu- 239 in a single pass through the core (corresponding to approximately 600 GWt-d/t). Comparable levels of burnup can be achieved using TRU material recovered from light water reactor (LWR) spent fuel. DB-VHTRs can also be deployed with Fast Breeder Reactors (FBRs) in a completely closed fuel cycle to provide both sustainability of nuclear fuel resources and flexible energy outputs, including hydrogen production and other process-heat applications.

Predictive analysis of the ITER poloidal field conductor insert (PFCI) test program

Zanino, R.*; Astrov, M.*; Bagnasco, M.*; Baker, W.*; Bellina, F.*; Ciazynski, D.*; Egorov, S. A.*; Kim, K.*; Kvitkovic, J. L.*; Lacroix, B.*; et al.

IEEE Transactions on Applied Superconductivity, 17(2), p.1353 - 1357, 2007/06

https://doi.org/10.1109/TASC.2007.899046

The PFCI will be tested at JAEA Naka, inside the bore of the ITER Central Solenoid Model Coil. The main test program are the DC characterization of the conductor, the measurement of AC losses in conductor, the hydraulic characterization, the stability and the quench propagation, and the effects of cycling electromagnetic load. Based on and in support of this test program, an extensive campaign of predictive analysis has been initiated on a subset of the above-mentioned test program items and the results of the comparison of selected predictions from different laboratories will be presented and discussed. A sudden quench at 5.7-6.2 K and 45 kA is predicted. The computed temperature increase at the winding outlet is about 0.5 K for the pulse. These results will be compared with the experiment and used for an accurate prediction of the PF coil performance.

Implications of NbTi short-sample test results and analysis for the ITER Poloidal Field Conductor Insert (PFCI)

Zanino, R.*; Bagnasco, M.*; Baker, W.*; Bellina, F.*; Bruzzone, P.*; della Corte, A.*; Ilyin, Y.*; Martovetsky, N.*; Mitchell, N.*; Muzzi, L.*; et al.

IEEE Transactions on Applied Superconductivity, 16(2), p.886 - 889, 2006/06

https://doi.org/10.1109/TASC.2006.873318

As the test of the PFCI is foreseen at JAERI Naka, Japan, it is essential to consider in detail the lessons learned from the short NbTi sample tests, as well as the issues left open after them, in order to develop a suitable test program of the PFCI aimed at bridging the extrapolation gap between measured strand and future PF coil performance. Here we consider in particular the following issues: (1) the actual possibility to quench the PFCI conductor in the TCS tests before quenching the intermediate joint, (2) the question of the so-called sudden or premature quench, based on SULTAN sample results, applying a recently developed multi-solid and multi-channel extension of the Mithrandir code to a short sample analysis; (3) the feasibility of the AC losses calorimetry in the PFCI. These results show that Tcs measurement and the calorimetric measurement of AC losses will be carried out successfully. However, we need further analytic works for the problem of the sudden quench.

Prospects for -particle diagnostics by CO laser collective Thomson scattering in ITER

Kondoh, Takashi; Richards, R. K.*; Hutchinson, D. P.*; Sugie, Tatsuo; Costley, A. E.*; Miura, Yukitoshi; Lee, S.*

Proceedings of 30th EPS Conference on Controlled Fusion and Plasma Physics (CD-ROM), 4 Pages, 2003/07

In order to understand the behavior of alpha-particles which are the dominant heat source in a burning plasma, it is necessary to measure the spatial distribution of the number of the alpha-particles and their energy spectrum. A collective Thomson scattering (CTS) system based on a pulsed CO laser is being developed and is under consideration for alpha-particle measurements on ITER. Heating beam ions (E = 1 MeV) are normally co-injected and have a similar velocity with alpha-particles in ITER. The CTS measurement can not, in general, distinguish beam ions and alpha-particles which have the same velocity. A vertical scattering geometry to distinguish between beam ions and alpha-particles is proposed. Calculations have shown that the vertically viewing CTS can resolve counter-travelling alphas without being masked by beam ions. Preliminary design of a beam line and a receiver system with the vertical scattering geometry has been developed. A proof-of-principle test on the CTS system using the JT-60U plasma is being conducted.