Random telegraph signal (RTS) in the Euclid IR H2RGs

International audienceEuclid is an ESA mission to map the geometry of the dark Universe with a planned launch date in 2021. Euclid is optimised for two primary cosmological probes, weak gravitational lensing and baryonic acoustic oscillations. They are implemented through two science instruments on-board Euclid, a visible imager (VIS) and a near-infrared photometer/spectrometer (NISP), which are being developed and built by the Euclid Consortium instrument development teams. The NISP instrument contains a large focal plane assembly of 16 Teledyne HgCdTe H2RG detectors with 2.3 μm cut-off wavelength and SIDECAR readout electronics. The performance of the detector systems is critical for the science return of the mission and extended on-ground tests are being performed for characterisation and calibration purposes. Special attention is given also to effects even on the scale of individual pixels, which are difficult to model and calibrate, and to identify any possible impact on science performance. This paper discusses the known effect of random telegraph signal (RTS) in a follow-on study of test results from the Euclid NISP detector system demonstrator model [1], addressing open issues and focusing on an in-depth analysis of the RTS behaviour over the pixel population on the studied Euclid H2RGs

Detector chain calibration strategy for the Euclid Flight IR H2RGs

International audienceEuclid is an ESA mission to map the geometry of the Dark Universe with a planned launch date in 2021.1 Two primary cosmological probes, weak gravitational lensing and baryonic acoustic oscillations, are implemented through a VISible imager (VIS) and a Near-Infrared Spectrometer and Photometer (NISP).2 The ground characterization of the NISP Flight Sensor Chip Systems (SCS) followed by the pixel response calibration aims to produce all informations to correct and control the accuracy of the signal. This work reports on the ground characterization of the NISP detector chain. The detector and electrical effects are likely to generate statistical fluctuations and systematic errors on the final flux measurement. The analysis strategies to maintain the pixel relative response accuracy within 1% is proposed in this work. The Euclid NISP test ow is presented and the main concerns of the detector chain calibration, such as non-linearity, charge trapping and de-trapping are discussed on the basis of the analysis of the flight detectors characterization data

Euclid flight H2RG IR detectors: per pixel conversion gain from on-ground characterization for the Euclid NISP instrument

International audienceEuclid is a major ESA mission for the study of dark energy planned to launch in 2021. Euclid will probe the expansion history of the Universe using weak lensing and baryonic acoustic oscillations probes. A survey of 15,000 deg2 of the sky with the instrument NISP (Near-Infrared Spectro-Photometer), in the 900 – 2100 nm band, will give both the photometric and spectrometric redshifts of tens of millions of galaxies. The 16 H2RG detectors of the NISP focal plane array are still being characterized at CPPM (Marseille). Already 16 out of 20 flight detectors have been tested and a straightforward analysis done. Performance of the dedicated test benches – in particular control of flux and temperature – as well as an overview of the test flow will be presented. This paper will present methods and some preliminary results on two detectors focusing on the determination of a per pixel conversion gain

Police et migrants

Depuis deux décennies, l'histoire des institutions policières et celle des migrations ont été fortement renouvelées. Le renouvellement de l'histoire des institutions policières a intéressé aussi bien les historiens que les juristes ou les sociologues, voire les professionnels de l'ordre public. Parallèlement, l'avènement comme champ de recherche à part entière de l'histoire de l'immigration et des étrangers en France a enrichi de questionnements inédits l'étude des populations mobiles, déjà fortement revivifiée par de nombreux travaux sur les sociétés rurales ou urbaines. Par la force des choses, ces deux histoires ne cessent de se croiser. Le souci du maintien de l'ordre confronté aux problèmes posés par une société de plus en plus mobile rencontre, à travers la relation police-migrants, un enjeu essentiel. La circulation et l'installation massive des étrangers sur le territoire français à partir de la fin du XIXe siècle, au moment de la consolidation du l'État national, constitue un paramètre important de la modernisation des institutions au sein de l'État-nation. À partir de là, interroger de façon spécifique le terrain où se rencontrent ces deux historiographies dynamiques est apparu comme une démarche féconde et nécessaire, puisqu'elle n'avait jamais été systématiquement conduite. Une trentaine de spécialistes de l'histoire des migrations et de la police, historiens, juristes et sociologues, confrontent leurs analyses dans cet ouvrage qui espère constituer une étape majeure dans l'évolution d'un vaste chantier aux implications très actuelles

Physical Characterization of a Wireless Radiotracer Detection System Based on Pixelated Silicon for in Vivo Brain Studies in Freely Moving Rats

BLUPS for the four phenotypic traits studied. Each row corresponds to one individual

Physical Characterization of a Wireless Radiotracer Detection System Based on Pixelated Silicon for in Vivo Brain Studies in Freely Moving Rats

An exciting challenge for neuro-physiological investigations remains the combination of brain imaging and behavioral studies, which associates molecular processes of neuronal communications to their related actions. PIXSIC presents novel strategy using a submillimeter pixellated probe for β+ radiotracer detection based on a reverse-biased, high-resistivity silicon diode; This fully autonomous detection system permits local, time resolved measurements of radiotracers in a volume of a few mm3 with the probe dipped into aqueous solutions of [18F] and [11C]. Preliminary implantation tests on a anaesthetized rats proved functionality of the PIXSIC probe in brain tissues. High spatial resolution allows for the visualization of radiotracer concentration in different brain regions with a temporal resolution of less than 2 second

A wireless beta-microprobe based on pixelated silicon for in vivo brain studies in freely moving rats

The investigation of neurophysiological mechanisms underlying the functional specificity of brain regions requires the development of technologies that are well adjusted to in vivo studies in small animals. An exciting challenge remains the combination of brain imaging and behavioural studies, which associates molecular processes of neuronal communications to their related actions. A pixelated intracerebral probe (PIXSIC) presents a novel strategy using a submillimetric probe for beta+ radiotracer detection based on a pixelated silicon diode that can be stereotaxically implanted in the brain region of interest. This fully autonomous detection system permits time-resolved high sensitivity measurements of radiotracerswith additional imaging features in freelymoving rats. An application-specific integrated circuit (ASIC) allows for parallel signal processing of each pixel and enables the wireless operation. All components of the detector were tested and characterized. The beta+ sensitivity of the system was determined with the probe dipped into radiotracer solutions.Monte Carlo simulations served to validate the experimental values and assess the contribution of gamma noise. Preliminary implantation tests on anaesthetized rats proved PIXSIC's functionality in brain tissue. High spatial resolution allows for the visualization of radiotracer concentration in different brain regions with high temporal resolution. (Some figures may appear in colour only in the online journal