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The design and test of a robot-compatible, radiation detection instrument providing simultaneous $\gamma $ -ray imaging and $\gamma $ -ray spectroscopy is described. The sensing system comprises a cerium bromide inorganic scintillation detector and a cylindrical, lead slot collimator that is configured with a robot-compatible, on-board data acquisition system. The mount for the sensor is a lightweight, bespoke 3-axis gimbal actuated by servos for pan, tilt and rotation of the collimator for imaging capability. This paper discusses the integration of this relatively low-cost radiation detection apparatus with a commercially available, Robot-Operating-System-controlled robotic platform (a Clearpath Robotics™ Jackal). The detection system is compliant with the power and mass payload constraints of the robot. Its performance has been evaluated by means of two practical examples: a) measurements in a laboratory environment to assess the ability of the system to resolve two caesium-137 point sources, and b) deployment at the Jožef Stefan Institute TRIGA Mark II research reactor to assess the ability of the system to characterise the $\gamma $ -ray emission at 1 kW from a horizontal tangential beam port in the reactor hall and from the reactor sample pool above the core.

At the present work, impedance spectroscopy of nanocrystalline silicon carbide (3C-SiC) has been investigated as a function of temperature. Nanocrystalline 3C-SiC particles irradiated by neutrons (2 × 1013 n cm− 2s− 1) up to 20 h. Impedance of neutron-irradiated nanocrystalline 3C-SiC has been studied at the temperature range of 100–400 K. Impedance spectra of the nanocrystal have been comparatively studied before and after neutron irradiation. The natures of conductivity and the metal—semiconductor transition temperature (TMS = 250 K, 325 K, and 370 K at the various frequencies) have been defined from the complex impedance spectroscopy. Polarization of nanocrystalline 3C-SiC increased corresponding to neutron irradiation duration. The mechanism of all effects observed in the experiments has been given in the work.

The premise behind this research is the characterisation and integration of a unique detector system on board a submersible, remotely-operated vehicle (ROV) for the end purpose of fuel debris characterisation at Fukushima Daiichi. Currently, at Fukushima Daiichi. Whilst precise knowledge of the location of the core debris at Fukushima is not known it is commonly assumed that fuel has leaked through into the base of the pedestal below and it is suggested that it may have moved outside of the pedestal into the lower plenum. The flooding of the reactor floors immediately following the Fukushima accident adds an extra element of complexity for the detection system requiring it to be submersible and to hold any detector system in water-tight confinement. The research presented here focusses on the use of a CeBr 3 inorganic scintillator detector with a unique configuration of an in-built HV supply for ease of integration within an ROV in a submerged environment. The detector has been tested in several environments: small wave tank for source identification and a TRIGA reactor and a 60Co irradiator. It is hoped that the CeBr 3 detector will constitute one component of an on-board detector payload to determine the suitability for the localisation and identification of fuel debris inside the cores at Fukushima.

The future circular collider (FCC) is foreseen as the next-generation ~100-km long synchrotron to be built in the Geneva area starting 2050. This machine is expected to reach an energy level of 100 TeV generating unprecedented radiation levels >100 times higher than in today’s large hadron collider (LHC). Current radiation monitoring system, like the RADMONs employed in the LHC, will not be capable to function and withstand this harsh environment. The development of a new ultrahigh fluence and dose radiation sensor is a key element to allow irradiation tests of FCC equipment and, at a later stage, to monitor radiation levels in the FCC itself. In this paper, we present an innovative dosimetry solution based on thin layers of metals, which resistivity is shown to increase significantly due to the accumulated displacement damage. After describing the fabrication techniques used to manufacture these radiation-dependent resistors, we show and discuss the results of the irradiation experiments carried out with neutrons (up to $10^{18}$ n/cm$^2$ at the JSI TRIGA reactor) and with protons (up to $5.2 \times 10^{16}$ p/cm$^2$ at CERN IRRAD Facility) to validate the proposed concept of possible ultrahigh fluence FCC dosimeter.