Data acquisition electronics and reconstruction software for directional detection of Dark Matter with MIMAC

Directional detection of galactic Dark Matter requires 3D reconstruction of low energy nuclear recoils tracks. A dedicated acquisition electronics with auto triggering feature and a real time track reconstruction software have been developed within the framework of the MIMAC project of detector. This auto-triggered acquisition electronic uses embedded processing to reduce data transfer to its useful part only, i.e. decoded coordinates of hit tracks and corresponding energy measurements. An acquisition software with on-line monitoring and 3D track reconstruction is also presented.Comment: 17 pages, 12 figure

The SAMPIC Waveform and Time to Digital Converter

Sce ElectroniqueInternational audienceSAMPIC is a Waveform and Time to DigitalConverter (WTDC) multichannel chip. Each of its 16 channelsassociates a DLL-based TDC providing a raw time with an ultrafastanalog memory allowing fine timing extraction as well asother parameters of the pulse. Each channel also integrates adiscriminator that can trigger itself independently or participateto a more complex trigger. After triggering, analog data isdigitized by an on-chip ADC and only that corresponding to aregion of interest is sent serially to the DAQ. The association ofthe raw and fine timings permits achieving timing resolutions of afew ps rms. The paper describes the detailed SAMPIC0architecture and reports its main measured performances

The Palomar Transient Factory: System Overview, Performance and First Results

The Palomar Transient Factory (PTF) is a fully-automated, wide-field survey aimed at a systematic exploration of the optical transient sky. The transient survey is performed using a new 8.1 square degree camera installed on the 48-inch Samuel Oschin telescope at Palomar Observatory; colors and light curves for detected transients are obtained with the automated Palomar 60-inch telescope. PTF uses eighty percent of the 1.2-m and fifty percent of the 1.5-m telescope time. With an exposure of 60-s the survey reaches a depth of approximately 21.3 in g' and 20.6 in R (5 sigma, median seeing). Four major experiments are planned for the five-year project: 1) a 5-day cadence supernova search; 2) a rapid transient search with cadences between 90 seconds and 1 day; 3) a search for eclipsing binaries and transiting planets in Orion; and 4) a 3-pi sr deep H-alpha survey. PTF provides automatic, realtime transient classification and follow up, as well as a database including every source detected in each frame. This paper summarizes the PTF project, including several months of on-sky performance tests of the new survey camera, the observing plans and the data reduction strategy. We conclude by detailing the first 51 PTF optical transient detections, found in commissioning data.Comment: 12 pages, 11 figures, 3 tables, submitted to PAS

Development of a miniaturised particle radiation monitor for Earth orbit

Geometry and algorithm design for a novel highly miniaturised radiation monitor (HMRM) for spacecraft in medium Earth orbit are presented. The HMRM device comprises a telescopic configuration of application-specific active pixel sensors enclosed in a titanium shield, with an estimated total mass of 52 g and volume of 15 cm3. The monitor is intended to provide real-time dosimetry and identification of energetic charged particles in fluxes of up to 108 cm-2 s-1 (omnidirectional). Achieving this capability with such a small instrument could open new prospects for radiation detection in space. The methodology followed for the design and optimisation of the particle detector geometry is explained and analysis algorithms - for real-time use within the monitor and for post-processing reconstruction of spectra - are presented. Simulations with the Geant4 toolkit are used to predict operational results in various Earth orbits. Early test results of a prototype monitor, including calibration of the pixel sensors, are also reported.Open Acces

Solar gamma ray monitor for OSO-H (0.3-10 MeV)

A gamma ray experiment to be flown aboard the OSO-7 spacecraft is described along with a history of the development of the experiment, a description of the gamma ray detector and its operation, and a short preliminary review of the scientific information obtained during the instruments' lifetime. The gamma ray detector operated an average of 18 hours a day for approximately 15 months. The majority of the data was collected in the solar and antisolar direction, but data at right angles to the spacecraft-sun line was also accumulated. In all, at least two full scans of the celestial sphere were completed

DARKNESS: A Microwave Kinetic Inductance Detector Integral Field Spectrograph for High-Contrast Astronomy

We present DARKNESS (the DARK-speckle Near-infrared Energy-resolving Superconducting Spectrophotometer), the first of several planned integral field spectrographs to use optical/near-infrared Microwave Kinetic Inductance Detectors (MKIDs) for high-contrast imaging. The photon counting and simultaneous low-resolution spectroscopy provided by MKIDs will enable real-time speckle control techniques and post-processing speckle suppression at framerates capable of resolving the atmospheric speckles that currently limit high-contrast imaging from the ground. DARKNESS is now operational behind the PALM-3000 extreme adaptive optics system and the Stellar Double Coronagraph at Palomar Observatory. Here we describe the motivation, design, and characterization of the instrument, early on-sky results, and future prospects.Comment: 17 pages, 17 figures. PASP Publishe

Development of low power front-end electronics for monolithic Active Pixel Sensors

The next generation High Energy Physics experiments require the development of novel radiation sensor technologies adequate to cover very large areas and suitable for extreme radiation conditions. In this field, thanks to its incomparable properties, silicon is still nowadays the dominant semiconductor used to build tracking detectors for ionizing particles. In several experiments all around the world, it is used to cover very large areas with the intent of tracking and identifying the crossing particles generated during the experiments. Different topologies of silicon sensors can be used for these applications but those commonly used for high rate environments are pixel sensors. This research activity focuses mainly on two particular types of these sensors: hybrid pixel sensors and monolithic active pixel sensors (MAPS). Modern detectors use intensively hybrid sensors due to their excellent properties. This technology indeed allows to develop sensor and electronics separately allowing a very effective optimization of each part of the device increasing in this way its versatility and allowing to meet most of the requirements of the new experiments. The hybrid technology is fast and also suitable for working in high radiation environments thanks to the use of high electrical fields for the charge collection. However, the production cost of those devices is much higher than other sensors because two different devices are required and also due to the additional cost for the bump bonding used to interconnect sensor and readout ASIC. On the other hand, monolithic sensors are based on the implementation of sensor and readout electronics in the same silicon wafer. Therefore this technology is much cheaper than the hybrid solution and allows to reduce significantly contribution of the detector to the material budget. However, traditional MAPS have some limitations in terms of speed, extension of the depletion volume, signal to noise ratio and radiation tolerance which make those devices unsuitable for the extreme environment of the new experiments. In this context, this work presents the development of a full depleted monolithic pixel sensor with a thickness of 300 μm which aims to overcome the main limitations of the conventional monolithics. The proposed device has properties similar to the hybrid solution but benefits of the low production cost typical of monolithics. The development of the device has been carried out by the collaboration between the University of Trento, INFN of Padova and INFN of Torino. In addition, thanks to the close collaboration with the experts of a silicon foundry, it was possible a tailored fabrication of the devices. Two ASICs of 2 mm × 2 mm have been developed in a customized double-sided CMOS technology with transistors of 1.2 V and 6 metal layers. The devices have been submitted to the foundry for fabrication on April 2016 and have been delivered for the testing phase on May 2017. A patent for the device has been granted in 2017. In the first part of this work, the state of the art of monolithics is given where hybrid and monolithics are compared. Then, the novel sensor is described in detail with the support of simulations to motivate important solutions adopted to reach the full depletion and to implement PMOS transistors avoiding the competitive charge collection. Some studies to highlight the huge limitations on design MAPS without access to the process data are presented to introduce the custom process used for the development of the device. The first ASIC is a test chip designed to contain test devices used to study important properties of the sensor like depletion and punch-through voltage. All the devices implemented in this ASIC are described in detail motivating the design solutions adopted. The second ASIC is the complete monolithic sensor called MATISSE (Monolithic AcTIve pixel SenSor Electronics) made by a matrix array of 24 × 24 pixels readout with the snapshot shutter technique. Each pixel is 50 μm×50 μm and is based on the same novel sensor. The chip is described in detail with the support of simulation results to motivate some strategies adopted during the design. Special emphasis is placed on the strategy used to design the readout chain with a wide output swing, low noise and excellent linearity with the use of high threshold transistors. Last but not least, in the last chapter the results collected during the characterization of the two prototypes for different wafers are presented. The data acquisition system developed is described and the electrical tests and measurements with active sources and lasers are reported. The measurements performed on the test structures show unwanted trapped charge in the backside oxide. The phenomenon is described putting special attention on an irradiation campaign performed in the test diodes to confirm and quantify this effect. All the results presented in this work aim to prove the device full depletion and the excellent properties of the embedded electronics implemented in these first prototypes