The effect of the displacement damage on the Charge Collection Efficiency in Silicon Drift Detectors for the LOFT satellite

The technology of Silicon Drift Detectors (SDDs) has been selected for the two instruments aboard the Large Observatory For X-ray Timing (LOFT) space mission. LOFT underwent a three year long assessment phase as candidate for the M3 launch opportunity within the "Cosmic Vision 2015 -- 2025" long-term science plan of the European Space Agency. During the LOFT assessment phase, we studied the displacement damage produced in the SDDs by the protons trapped in the Earth's magnetosphere. In a previous paper we discussed the effects of the Non Ionising Energy Losses from protons on the SDD leakage current. In this paper we report the measurement of the variation of Charge Collection Efficiency produced by displacement damage caused by protons and the comparison with the expected damage in orbit.Comment: 17 pages, 7 figures. Accepted for publication by Journal of Instrumentatio

Waveform Approach for Assessing Conformity of CISPR 16-1-1 Measuring Receivers

An alternative approach for assessing the conformity of electromagnetic interference measuring receivers with respect to the baseline CISPR 16-1-1 requirements is proposed. The method’s core is based on the generation of digitally synthesized complex waveforms comprising multisine excitation signals and modulated pulses. The superposition of multiple narrowband reference signals populating the standard frequency bands allows for a single-stage evaluation of the receiver’s voltage accuracy and frequency selectivity. Moreover, characterizing the response of the weighting detectors using modulated pulses is more repeatable and less restrictive than the conventional approach. This methodology significantly reduces the amount of time required to complete the verification of the receiver’s baseline magnitudes, because time-domain measurements enable a broadband assessment while the typical calibration methodology follows the time-consuming narrow band frequency sweep scheme. Since the reference signals are generated using arbitrary waveform generators, they can be easily reproduced from a standard numerical vector. For different test receivers, the results of such assessment are presented in the 9 kHz–1 GHz frequency range. Finally, a discussion on the measurement uncertainty of this methodology for assessing measuring receivers is given.Postprint (author's final draft

Multi-platform solution for data acquisition

Analogue data acquisition is a common task which has application in several fields such as scientific research, industry, food production, safety, and environmental monitoring. It can be carried out either using systems designed ad-hoc for a specific application or by using general-purpose Digital Acquisition Boards (DAQ). Several DAQ solutions are nowadays available on the market, however, most of them are extremely expensive and come as commercial closed products, a factor which prevents users to adapt the system to their specific applications and limits the product compatibility to few operating systems or platforms. This paper describes the design and the preliminary metrological characterisation of a digital data acquisition solution based on the Teensyduino Development Board. The aim of the project is to create a hardware and software infrastructure suitable to be employed on several operating systems and that can be freely modified by the users when required. Teensyduino board is a well-known development platform which is characterised by high computing performance and USB support. Taking advantage of the Teensyduino features, the proposed system is easy to be calibrated and used, and it provides functions and performance comparable to many commercial DAQs, but at a significantly lower cost