In the frame of the C-BORD project, five innovate technology pillars for Non-Intrusive Inspection (NII) are under development. Freight containers are potential means for smuggling, drug trafficking ...and transport of dangerous or illicit substances. The goal of the C-BORD project is to increase interdiction of illicit or dangerous materials in containerized freight and deliver new capabilities against critical operational requirements and constrains. Particularly, the aim of the project is to increase throughput of the container per time unit, reduce cost and tome of cargo inspection and minimize the false negative and false positive alarm ratios. Finally, thanks to field trials organized during the project, capability of these systems will be proven and the C-BORD Toolbox usefulness will be validated by end users under real conditions at sea and border crosses.
A custom designed cryostat was constructed to measure the response of a CsI:T1 scintillator in temperature range from -183 degrees C up to +90 degrees C. The light readout was realized using a SiPM ...developed by FBK in near ultraviolet high density (NUV-HD) technology. The crystal and the SiPM were installed on separated copper frames. The crystal was cooled down by liquid nitrogen, while the SiPM was kept at temperature close to room temperature. A separation of 1 mm was kept between the crystal and the photodetector to ensure thermal isolation. The temperature of the crystal could be varied by heaters on the scintillator frame and was continuously monitored using a coil shaped resistance thermometer. The CsI:T1 scintillation decay profiles were recorded in the entire temperature range provided by the cryostat.
This paper presents the results of the fast neutron irradiation (E\(_n\) > 0.5MeV) of an EJ-276 scintillator performed in the MARIA research reactor with fluence up to 5.3\(\times\)10\(^{15}\) ...particles/cm\(^2\). In our work, four samples with size \(\phi\)25.4~mm\(\times\)5~mm were tested. The changes in the light yield, emission and absorption spectrum and neutron/gamma discrimination using PuBe source before and after irradiation are presented. The figure of merit in neutron/gamma discrimination based on the charge integration method for different neutron fluences and different short gate integration times are determined.
This paper presents the results of the proton irradiation of silicon photomulipliers (SiPMs) by mono-energetic 170 MeV protons with fluence up to 4.6\(\times\)10\(^{9}\) particles/cm\(^2\). In our ...work, three types of silicon photodetectors from Hamamatsu with areas 3\(\times\)3 mm\(^2\) and different subpixel sizes of 25\(\times\)25 \(\mu\)m\(^2\), 50\(\times\)50 \(\mu\)m\(^2\), and 75\(\times\)75 \(\mu\)m\(^2\) were used. The changes in the SiPM dark count rate (DCR) spectrum before and after irradiation in temperatures in the range of 20 \(^\circ\)C to -65 \(^\circ\)C are presented. The influence of the DCR changes on the energy resolution of the 662 keV gamma line from the \(^{137}\)Cs for a non-irradiated GAGG:Ce (1\(\%\)) scintillator is investigated. The time period of usability of the SiPM detector irradiated by protons in cosmic space was estimated.
A custom designed cryostat was constructed to measure the response of a CsI:Tl scintillator in temperature range from - 183 ^{circ}\mathrm {C} up to +90 ^{circ}\mathrm {C}. The light readout was ...realized using a SiPM developed by FBK in near ultraviolet high density (NUV-HD) technology. The crystal and the SiPM were installed on separated copper frames. The crystal was cooled down by liquid nitrogen, while the SiPM was kept at temperature close to room temperature. A separation of 1 mm was kept between the crystal and the photodetector to ensure thermal isolation. The temperature of the crystal could be varied by heaters on the scintillator frame and was continuously monitored using a coil shaped resistance thermometer. The CsI:Tl scintillation decay profiles were recorded in the entire temperature range provided by the cryostat.
A custom designed cryostat was constructed to measure the response of a CsI:Tl scintillator at temperatures close to the boiling point of liquid nitrogen (LN 2 ). The scintillation light was ...collected by an HUV-HD SiPM from FBK with 6×6 mm 2 area and 25×25 μm 2 cell pitch. The crystal size was 5×6×7 mm 3 . All surfaces except the one facing the SiPM were covered with Teflon tape to enhance light collection by the photodetector. The performance of the experimental setup was verified at room temperature using analog electronics for signal processing. The crystal was mounted on a copper frame placed inside the LN 2 cryostat. Since our goal was to measure the scintillation decay profiles, and the SiPM response at low temperatures becomes substantially slower than that observed at room temperature, the SiPM was mounted on a separate copper frame connected with the outer housing to keep it close to room temperature. The separation between the crystal surface and the SiPM was about 1.5 mm at room temperature, and it became smaller once the setup was cooled down to LN 2 temperature, but even so the crystal and the photodetector were still separated. This approach allowed us to analyze scintillation pulse shapes of CsI:Tl at LN 2 temperatures. An energy spectrum of 662 keV γ-rays from a 137 Cs source was also recorded. The light yield of the CsI:Tl sample at LN 2 temperature stands at about 6 % ÷ 8 % of the value observed at room temperature.
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