We present a prototype time-to-digital converter (TDC) for measuring the time of arrival of signals generated by interactions between an alpha source and a silicon strip sensor. The generated charge, in a form of small current pulses, is amplified and shaped by an ASIC that generates differential analog waveforms. An Artix7 FPGA is used to interface with 22 channels carrying these waveforms. The analog voltages are directly connected to FPGA inputs configured in LVDS (Low-Voltage Differential Signaling) mode. The FPGA input is configured as an DDR (Double Data Rate) buffer to operate in the oversampling mode, resulting in a sampling rate of 2.4 GS/s. As the FPGA inputs are analog, the 0→1 and 1→0 transitions suffers from bounce due to switching noise. Accurate extraction of the transition time thus requires an appropriate digital filter. Several filter designs are presented, along with their performance on real signals. The time resolution of the resulting TDC alone is approximately 200 ps rms. System-level measurements that include a 100 pF capacitance at the ASIC inputs reveal an increased timing variance of 520 ps rms.

Large silicon photomultiplier (SiPM) arrays are used to collect scintillation light in noble liquid detectors such as DarkSide, nEXO, MEGII, ProtoDUNE and DUNE. The requirement of strict radiopurity for some of these detectors necessitate the use of fused silica substrate as the carrier of through silicon via (TSV) SiPM arrays with through quartz via (TQV) for front to backside electrical connections. We characterize the photodetection of these SiPM arrays and demonstrate the single-photoelectron detection in cryogenic environments. The intrinsically larger capacitance (a few nF/cm 2 ) of these SiPM arrays require a light readout concept by weakly couple the photoelectron signal to a charge sensitive amplifier. We will explore the performance on this light readout system using arrays of TSV SiPM tiles.

Germanium has been the material of choice in detectors of high-energy X-rays and gamma rays for many years, largely because it is relatively easy to obtain high-quality material in large quantities...

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We have developed a series of monolithic multi-element germanium detectors, based on sensor arrays produced by the Forschungzentrum Julich, and on Application-specific integrated circuits (ASICs) developed at Brookhaven. Devices have been made with element counts ranging from 64 to 384. These detectors are being used at NSLS-II and APS for a range of diffraction experiments, both monochromatic and energy-dispersive. Compact and powerful readout systems have been developed, based on the new generation of FPGA system-on-chip devices, which provide closely coupled multi-core processors embedded in large gate arrays. We will discuss the technical details of the systems, and present some of the results from them.

A new SDD-Maia detector is being currently developed, consisting of an array of 384 silicon drift detectors (SDDs), each having a surface area of 1 mm 2 . The shape of each individual pixel is square in order to coincide with the footprint of the diode-based Maia detector. Each SDD pixel is made of a few concentric “rings” that supply a voltage gradient to form the drift field within the silicon. The detector has a double metal scheme that supplies biases to the single SDD rings. All 384 anodes of SDDs are connected to individual electronic channels. This effort was motivated by the need of improving the energy resolution and the throughput of existing diode-based Maia detectors.

A new Maia detector is being currently developed, consisting of an array of 384 silicon drift detectors (SDDs), each having an area of 1 mm2. The detector features a new double metal scheme that supplies biases to the pixel SDD rings. All 384 anodes of SDDs are meant to be connected to individual electronic channels. This effort was motivated by the need of improving the energy resolution and the throughput of the existing Maia detectors whose pixels are based on p-in-n diodes. In order to use the existing circuit boards and back-end electronics that have already developed for the original Maia, the SDD-Maia detector was designed with an identical footprint, after replacing the p-in-n diodes with SDDs. The design, fabrication and performance of a first prototype detector will be presented.

Maia is an advanced system designed specifically for scanning x-ray fluorescence microprobe applications. It consists of a large array of photodiode detectors and associated signal processing, closely coupled to an FPGA-based control and analysis system. In this paper we will describe the architecture and construction of the system.

The Maia detector system is engineered for energy dispersive x‐ray fluorescence spectroscopy and elemental imaging at photon rates exceeding 107/s, integrated scanning of samples for pixel transit times as small as 50μs and high definition images of 108 pixels and real‐time processing of detected events for spectral deconvolution and online display of pure elemental images. The system developed by CSIRO and BNL combines a planar silicon 384 detector array, application‐specific integrated circuits for pulse shaping and peak detection and sampling and optical data transmission to an FPGA‐based pipelined, parallel processor. This paper describes the system and the underpinning engineering solutions.

Measurement of-rays from the surface of objects can tell us about the chemical composition. Absorption of radiation causes characteristic fluorescence from material being irradiated. By measuring the spectrum ofthe radiation and identifying lines in the spectrum, the emitting element (s) can be identified.

A method developed to produce an X-ray active matrix pixel sensor (XAMPS) is reported. Several problems had been encountered during the production, but solutions to all of them were found. We will present the design of the detector, justifying the choice of high resistivity silicon as the material for XAMPS. Production processing will be described with emphasis on encountered problems and their solutions. The detectors were produced and one of them was tested within the BNL scanning transmission electron microscope (STEM) for recording data.

We have developed a thick film multi-chip module for readout of silicon drift (or low capacitance ∼200fF) detectors. Main elements of the module include a custom 16-channel NPN-BJT preamplifier-shaper (PASA) and a custom 16-channel CMOS Switched Capacitor Array (SCA). The primary design criteria of the module were the minimizations of the power (12mW/channel), noise (ENC=490e−rms), size (20.5mm×63mm), and radiation length (1.4%). We will discuss various aspects of the PASA design, with emphasis on the preamplifier feedback network. The SCA is a modification of an integrated circuit that has been previously described [1]; its design features specific to its application in the SVT (Silicon Vertex Tracker in the STAR experiment at RHIC) will be discussed. The 240-channel multi-chip module is a circuit with five metal layers fabricated in thick film technology on a beryllia substrate and contains 35 custom and commercial integrated circuits. It has been recently integrated with silicon drift detectors in both a prototype system assembly for the SVT and a silicon drift array for the E896 experiment at the Alternating Gradient Synchrotron at the Brookhaven National Laboratory. We will discuss features of the module's design and fabrication, report the test results, and emphasize its performance both on the bench and under experimental conditions.

Large linear silicon drift detectors have been developed and are in production for use in several experiments. Recently 15 detectors were used as a tracking device in BNL-AGS heavy ion experiment (E896). The detectors were successfully operated in a 6.2 T magnetic field. The behavior of the detectors, such as drift uniformity, resolution, and charge collection efficiency are presented. The effect of the environment on the detector performance is discussed. Some results from the experimental run are presented. The detectors performed well in an experimental environmental. This is the first tracking application of these detectors.