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Ion accelerators have been used by material scientists for decades to investigate radiation damage formation in nuclear materials and thus to emulate neutron-induced changes. The versatility of conditions in terms of particle energy, dose rate, fluence, etc., is a key asset of ion beams allowing for fully instrumented analytical studies. In addition, very short irradiation times and handling of non-radioactive samples dramatically curtail the global cost and duration as compared to in-reactor testing. Coupling of two or more beams, use of heated/cooled sample holders, and implementation of in situ characterization and microscopy pave the way to real time observation of microstructural and property evolution in various extreme radiation conditions more closely mimicking the nuclear environments. For these reasons, multiple ion beam facilities have been commissioned worldwide. In France, under the auspices of the Université Paris-Saclay, the JANNuS platform for 'Joint Accelerators for Nanosciences and Nuclear Simulation' comprises five ion implanter and electrostatic accelerators with complementary performances. At CSNSM (CNRS & Univ Paris-Sud, Orsay), a 200 kV Transmission Electron Microscope is coupled to an accelerator and an implanter for in situ observation of microstructure modifications induced by ion beams in a material, making important contribution to the understanding of physical phenomena at the nanoscale. At CEA Paris-Saclay, the unique triple beam facility in Europe allows the simultaneous irradiation with heavy ions (like Fe, W) for nuclear recoil damage and implantation of a large array of ions including gasses for well-controlled modelling-oriented experiments. Several classes of materials are of interest for the nuclear industry ranging from metals and alloys, to oxides or glasses and carbides. This paper gives selected examples that illustrate the use of JANNuS ion beams in investigating the radiation resistance of structural materials for today's and tomorrow's nuclear reactors. [ABSTRACT FROM AUTHOR]

Approximately 900 children/adolescents are treated with radiotherapy (RT) every year in France. However, among the 80% of survivors, the cumulative incidence of long-term morbidity – including second malignancies - reach 73.4% thirty years after the cancer diagnosis. Identifying a priori the subjects at risk for RT sequelae is a major challenge of pediatric oncology. Individual radiosensitivity (IRS) of children/adolescents is unknown at this time. The cellular response to radiation depends on the recognition and repair of radiation-induced DNA double-strand breaks (DSB). Unrepaired DSB as well as a delay in the intra nuclear activation of the pATM protein are common features to patients with RT toxicity. From these conclusions, we proposed and retrospectively validated a functional IRS immunofluorescence assay based on Radio-Induced ATM Nucleoshuttling (RIANS) (Granzotto et al, 2016). The purpose of this study was to define prospectively the predictive impact of RIANS assay in children. Patients of the ARPEGE prospective open-label, non-randomized multicenter clinical trial were included in the study and prospectively evaluated for early toxicities. For each patient, skin samples were collected prior RT to raise a primary dermal fibroblast line and carry out in blind the RIANS assay. Different endpoints were measured: residual double-strand breaks at 24 h (γH2AX marker), pATM foci at 10 min and 1 h (pATM marker) and micronuclei at 24 h respectively after ex vivo radiation (2 Gy). The procedures were repeated in triplicates in blind in two independent expert centers (Neolys and Institut de Cancerologie de Lorraine). In parallel early toxicity was reported according to NCI-CTCAE v4.0 three months after the completion of RT. Patients with grade <2 or ≥2 toxicity were considered as radioresistant (RR) and radiosensitive (RS) respectively. We correlated the parameters of the RIANS assay according to toxicity with logistic regression. Among the 29 analyzable patients, 37 % exhibit brain cancers, 10% Hodgkin lymphomas, 10% nephroblastoma, 10% neuroblastoma, 10% Ewing cancer and 13% malignant mesenchymal cancer. The mean delivered dose was 32.5 Gy (range 1,5 - 60 Gy) with fractionation between 1.5 to 2 Gy. 16/29 (56%) patients were clinically considered as RS. There was no significant difference in total dose delivered between the two groups. Among the radiobiological factors tested, the number of Micronuclei at 24h post irradiation provided the best discrimination among RS patients (p-value= 0.0216). Overall, the RIANS assay provided the following performance: sensitivity=0.82, specificity=0.70 and AUC=0.75 (0.550-0.888). ARPEGE is the first study to document the distribution of IRS in such a population. Screening hypersensitive patients would be a major step forward in the management of cancers, opening a way to personalized pediatric oncology. [ABSTRACT FROM AUTHOR]

Abstract: This work presents the first held at Liverpool University measurements of pixel sensors with n-type readout implant in the p-type bulk before and after irradiation of samples by 24GeV protons to doses 7×1015 and 1.5×1016 protons/cm2. A comparison is given for two measurement techniques; one based on the FE-I3 readout chip designed for the ATLAS and the other using the Beetle chip developed for the LHCb experiments at CERN. [Copyright &y& Elsevier]

Abstract: A new ATLAS pixel chip FE-I4 is being developed for use in upgraded LHC luminosity environments, including the near-term Insertable B-Layer (IBL) upgrade. FE-I4 is designed in a 130nm CMOS technology, presenting advantages in terms of radiation tolerance and digital logic density compared to the CMOS technology used for the current ATLAS pixel IC, FE-I3. The FE-I4 architecture is based on an array of 80×336 pixels, each , consisting of analog and digital sections. In the summer 2010, a first full scale prototype FE-I4A was submitted for an engineering run. This IC features the full scale pixel array as well as the complex periphery of the future full-size FE-I4. The FE-I4A contains also various extra test features which should prove very useful for the chip characterization, but deviate from the needs for standard operation of the final FE-I4 for IBL. In this paper, focus will be brought to the various features implemented in the FE-I4A submission, while also underlining the main differences between the FE-I4A IC and the final FE-I4 as envisioned for IBL. [Copyright &y& Elsevier]

Abstract: The LHC accelerator complex will undergo a programme of consolidation and upgrade of various components, with the goal of exceeding a peak luminosity of (original design figure) around the year 2012; to eventually reach values close to . The increase in luminosity poses new challenges to the detector operation, both in terms of instantaneous and integrated particle rates. In CMS, the systems that have been identified as requiring substantial upgrades are the Tracker and the Level 1 trigger. The tracking system needs higher readout granularity and higher radiation tolerance, at the same time with reduced power dissipation and a smaller material budget, which are already limiting the performance of the present detector. The trigger system needs to include tracking information at Level 1, to maintain an acceptable rate without losing efficiency for physics channels. These requirements further complicate the design of a new Tracker detector and its readout architecture. This report describes the current status of our CMS Tracker upgrade activities. [Copyright &y& Elsevier]

Abstract: Optical links are used for data transmission of the ATLAS inner detector in a radiation hazard environment at the Large Hadron Collider (LHC). The radiation tolerance is studied for the opto-electronics of GaAs VCSEL and epitaxial Si PIN with 30 and 70MeV protons at CYRIC. High speed Si and GaAs PIN photo-diodes are also investigated for upgrade to super-LHC. The annealing of GaAs VCSEL by charge injection is characterized. The GaAs devices show approximately linear degradations to fluence. The dependence on proton energy is compared to the Non-Ionizing Energy Loss calculations. [Copyright &y& Elsevier]

Abstract: The ATLAS collaboration R&D group “Development of n-in-p Silicon Sensors for very high radiation environment” has developed single-sided p-type 9.75cm×9.75cm sensors with an n-type readout strips having radiation tolerance against the 1015 1-MeV neutron equivalent (neq)/cm2 fluence expected in the Super Large Hadron Collider. The compiled results of an evaluation of the bulk and strip parameter characteristics of 19 new non-irradiated sensors manufactured by Hamamatsu Photonics are presented in this paper. It was verified in detail that the sensors comply with the technical specifications required before irradiation. The reverse bias voltage dependence of various parameters, frequency dependence of tested capacitances, and strip scans of more than 23,000 strips as a test of parameter uniformity and strip quality over the whole sensor area have been carried out at Stony Brook University, Cambridge University, University of Geneva, and Academy of Sciences of CR and Charles University in Prague. No openings, shorts, or pinholes were observed on all tested strips, confirming the high quality of sensors made by Hamamatsu Photonics. [Copyright &y& Elsevier]