CAGIRE: a wide-field NIR imager for the COLIBRI 1.3 meter robotic telescope

The use of high energy transients such as Gamma Ray Bursts (GRBs) as probes of the distant universe relies on the close collaboration between space and ground facilities. In this context, the Sino-French mission SVOM has been designed to combine a space and a ground segment and to make the most of their synergy. On the ground, the 1.3 meter robotic telescope COLIBRI, jointly developed by France and Mexico, will quickly point the sources detected by the space hard X-ray imager ECLAIRs, in order to detect and localise their visible/NIR counterpart and alert large telescopes in minutes. COLIBRI is equipped with two visible cameras, called DDRAGO-blue and DDRAGO-red, and an infrared camera, called CAGIRE, designed for the study of high redshift GRBs candidates. Being a low-noise NIR camera mounted at the focus of an alt-azimutal robotic telescope imposes specific requirements on CAGIRE. We describe here the main characteristics of the camera: its optical, mechanical and electronics architecture, the ALFA detector, and the operation of the camera on the telescope. The instrument description is completed by three sections presenting the calibration strategy, an image simulator incorporating known detector effects, and the automatic reduction software for the ramps acquired by the detector. This paper aims at providing an overview of the instrument before its installation on the telescope.Comment: Accepted by Experimental Astronom

Temperature-dependent adsorption of tellurium and mercury species on cadmium telluride studied by spectroscopic ellipsometry.

Temperature-dependent adsorption of tellurium and mercury species on cadmium telluride studied by spectroscopic ellipsometry

Status of the development of 2k2 IR FPAs for astronomy and space in Europe

International audienceWe report on the development of short wave infrared (SWIR) imaging arrays for astronomy and space observation in Europe. LETI and Sofradir demonstrated 640x480 SWIR HgCdTe (MCT) arrays geared at low flux, low dark noise operation. Currently, we are developing 2048x2048 arrays mated to a newly developed ROIC. In parallel, the European Space Agency and the European Commission are funding the development and industrialization of 4 '' CdZnTe substrates and HgCdTe epitaxy. These large wafers are needed to achieve the necessary economies of scale and address the need for even larger arrays. HgCdTe SWIR detector performance at LETI/Sofradir is known from previous programs and will be discussed here. However, we will only be able to summarize the features and specifications of the new 2048x2048 detectors which are still at a prototype stage

Evidence of tricuspid valve remodeling in patients with severe mitral regurgitation independently of degree of functional tricuspid regurgitation: a two- and three-dimensional echocardiographic study

The study aim was to evaluate whether, in patients with severe mitral regurgitation (MR), tricuspid valve remodeling was independent of the degree of functional tricuspid regurgitation (FTR) present. Whether any differences in the analysis remodeling, as assessed by two-dimensional (2D) and three-dimensional (3D) echocardiography, can be demonstrated was also addressed

Current clinical applications of transthoracic three-dimensional echocardiography

The advent of three-dimensional echocardiography (3DE) has significantly improved the impact of non-invasive imaging on our understanding and management of cardiac diseases in clinical practice. Transthoracic 3DE enables an easier, more accurate and reproducible interpretation of the complex cardiac anatomy, overcoming the intrinsic limitations of conventional echocardiography. The availability of unprecedented views of cardiac structures from any perspective in the beating heart provides valuable clinical information and new levels of confidence in diagnosing heart disease. One major advantage of the third dimension is the improvement in the accuracy and reproducibility of chamber volume measurement by eliminating geometric assumptions and errors caused by foreshortened views. Another benefit of 3DE is the realistic en face views of heart valves, enabling a better appreciation of the severity and mechanisms of valve diseases in a unique, noninvasive manner. The purpose of this review is to provide readers with an update on the current clinical applications of transthoracic 3DE, emphasizing the incremental benefits of 3DE over conventional two-dimensional echocardiography

Comprehensive analysis of left ventricular geometry and function by three-dimensional echocardiography in healthy adults

BACKGROUND: Recent European Association of Echocardiography and American Society of Echocardiography guidelines on three-dimensional echocardiography state that normal values of left ventricular (LV) parameters for age and body size remain to be established. METHODS: In 226 consecutive healthy subjects (125 women; age range, 18-76 years), comprehensive three-dimensional echocardiographic analyses of LV parameters were performed, and values were compared with those obtained by conventional echocardiography. RESULTS: Upper reference values (mean+ 2 SDs) for three-dimensional LV end-diastolic and end-systolic volumes were 85 and 34 mL/m(2) in men and 72 and 28 mL/m(2) in women, respectively. Indexing LV volumes to body surface area did not eliminate gender differences. Lower reference values (mean - 2 SDs) for ejection fraction were 54% in men and 57% in women and for stroke volume were 25 and 24 mL/m(2), respectively. Upper reference values for LV mass were 97 g/m(2) in men and 90 g/m(2) in women and for end-diastolic sphericity index were 0.49 and 0.48, respectively. Significant age dependency of LV parameters was identified and reported across age groups. Three-dimensional echocardiographic LV volumes were larger, ejection fraction was similar, and LV stroke volume and mass were significantly smaller in comparison with the corresponding values obtained by conventional echocardiography. CONCLUSIONS: The investigators report a comprehensive analysis of LV geometry and function using three-dimensional echocardiography in a relatively large cohort of healthy Caucasian subjects with a wide age range. These may serve to establish age-specific and gender-specific reference ranges, which are crucial for the routine implementation of three-dimensional echocardiography to detect LV remodeling and dysfunction in clinical practice