A novel approach for designing the next generation of vertex detectors foresees to employ wafer-scale sensors that can be bent to truly cylindrical geometries after thinning them to thicknesses of ...20–40 μm. To solidify this concept, the feasibility of operating bent MAPS was demonstrated using 1.5cm×3cm ALPIDE chips. Already with their thickness of 50µm, they can be successfully bent to radii of about 2cm without any signs of mechanical or electrical damage. During a subsequent characterisation using a 5.4GeV electron beam, it was further confirmed that they preserve their full electrical functionality as well as particle detection performance.
In this article, the bending procedure and the setup used for characterisation are detailed. Furthermore, the analysis of the beam test, including the measurement of the detection efficiency as a function of beam position and local inclination angle, is discussed. The results show that the sensors maintain their excellent performance after bending to radii of 2cm, with detection efficiencies above 99.9% at typical operating conditions, paving the way towards a new class of detectors with unprecedented low material budget and ideal geometrical properties.
Hospitals in many cities are merging to form local multihospital systems. However, although the conventional wisdom is that these systems will generate efficiencies in the production of services, ...surprisingly little systematic evidence exists to support this view. To fill this research gap, and to determine the benefits of horizontal integration, a cross-sectional analysis of local hospital systems in the late 1980s and then in the early 1990s was done. In both studies it was found that the benefits of horizontal integration stem from greater efficiencies in marketing hospital systems to the community rather than from efficiencies in the production of services.
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