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To achieve the physics goals of future colliders, it is necessary to develop novel, radiation-hard silicon sensors for their tracking detectors. We target the replacement of hybrid pixel detectors with Depleted Monolithic Active Pixel Sensors (DMAPS) that are radiation-hard, monolithic CMOS sensors. We have designed, manufactured and tested the MALTA series of sensors, which are DMAPS in the 180 nm TowerJazz CMOS imaging technology. MALTA have a pixel pitch well below current hybrid pixel detectors, high time resolution (< 2 ns) and excellent charge collection efficiency across pixel geometries. These sensors have a total silicon thickness of between 50–300 μ m, implying reduced material budgets and multiple scattering rates for future detectors which utilise such technology. Furthermore, their monolithic design bypasses the costly stage of bump-bonding in hybrid sensors and can substantially reduce detector costs. This contribution presents the latest results from characterisation studies of the MALTA2 sensors, including results demonstrating the radiation tolerance of these sensors. [ABSTRACT FROM AUTHOR]

The upgrade of the MALTA DMAPS designed in Tower 180 nm CMOS Imaging process will implement the numerous modifications, as well as front-end changes in order to boost the charge collection efficiency after the targeted fluence of 1x10 15 1 MeV n e q / cm 2 . The effectiveness of these changes have been demonstrated in recent measurements with a small-scale Mini-MALTA demonstrator chip. Multiple changes in the digital periphery are proposed: The asynchronous address generator will be revised to provide more control over the pulse length. The Synchronization memory will be upgraded with the goal of achieving a sub-nanosecond timing resolution. Serial chip to chip data transfer will be prototyped, in order to gauge the plausibility of implementation on a future full sized chip. Apart from these changes, research of the overall sensor architecture will be discussed as well. [ABSTRACT FROM AUTHOR]

Abstract: Terradex project aims to realise an accurate and programmable multiparametric tool which will measure relevant physical quantities such as observation time, energy and type of all decay products of three naturally occurring decay chains of uranium and thorium series present in nature as well as the decay products of man-made radioactivity. The measurements described in this work are based on the performance tests of the first version of an instrument that is designed to provide high counting accuracy, by introducing self-triggering, delayed time-coincidence technique, of products of a given decay chain. In order to qualify the technique and to calibrate the Terradex, a 222Rn source is used. The continuous and accurate monitoring of radon concentration in air is realised by observing the alpha and beta particles produced by the decay of 222Rn and its daughters and tag each of them with a precise occurrence time. The validity of delayed coincident technique by using the state of the art electronics with application of novel data sampling and analysis methods are discussed. The flexibility of sampling protocols and the advantages of online calibration capability to achieve the highest level of precision in natural and man-made radiation measurements are also described. [Copyright &y& Elsevier]