Abstract-Electron multiplying charge-coupled devices (EMCCDs) enable imaging with subelectron noise up to video frame rates and beyond, providing the multiplication gain is sufficiently high. The ultra-low noise, high resolution, high-quantum efficiency, and robustness to over exposure make these sensors ideally suited to applications traditionally served by image intensifiers. One important performance parameter of such low-light imaging systems is the noise introduced by the gain process. This work investigates the noise introduced by the electron multiplication within the EMCCD. The theory and measurements of the excess noise factor are presented. The measurement technique for determining the excess noise factor is described in detail. The results show that the noise performance matches that of the ideal staircase avalanche photodiode. A Monte Carlo method for simulating the low-light level images is demonstrated and the results compared with practical experience.Index Terms-Charge-coupled devices (CCD), image intensifiers, low-light level imaging, noise, photon counting, single photon detection.

Hepatitis E virus (HEV) is a major public health concern in developing countries where the primary transmission is via contaminated water. Zoonotic HEV cases have been increasingly described in Europe, Japan, and the United States, with pigs representing the main animal reservoir of infection. We report an unusual acute hepatitis infection in a previously healthy man caused by a rat HEV with a considerably divergent genomic sequence compared with other rat HEV strains. It is possible that rat HEV is an underrecognized cause of hepatitis infection, and further studies are necessary to elucidate its potential risk and mode of transmission.

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International audienceThis paper focuses on the Dark Current-Random Telegraph Signal (DC-RTS) in solid-state image sensors. The DC-RTS is investigated in several bulk materials, for different surface interfaces and for different trench isolation interfaces. The main parameter used to characterize the DC-RTS is the transition maximum amplitude which seems to be the most appropriate for studying the phenomenon and identifying its origin. Proton, neutron and Co-60 Gamma-ray irradiations are used to study DC-RTS induced by both Total Ionizing Dose (TID) and Displacement damage (Dd) dose. Conclusions are drawn by analyzing the correlation between the exponential slope of the transition maximum amplitude histogram and the location of the DC-RTS-induced defects. The presented results can be extrapolated to predict DC-RTS distributions in various kinds of solid state image sensors

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