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We describe the newest generation of the SLAC Microresonator RF (SMuRF) electronics, a warm digital control and readout system for microwave-frequency resonator-based cryogenic detector and multiplexer systems, such as microwave superconducting quantum interference device multiplexers (μmux) or microwave kinetic inductance detectors. Ultra-sensitive measurements in particle physics and astronomy increasingly rely on large arrays of cryogenic sensors, which in turn necessitate highly multiplexed readout and accompanying room-temperature electronics. Microwave-frequency resonators are a popular tool for cryogenic multiplexing, with the potential to multiplex thousands of detector channels on one readout line. The SMuRF system provides the capability for reading out up to 3328 channels across a 4–8 GHz bandwidth. Notably, the SMuRF system is unique in its implementation of a closed-loop tone-tracking algorithm that minimizes RF power transmitted to the cold amplifier, substantially relaxing system linearity requirements and effective noise from intermodulation products. Here, we present a description of the hardware, firmware, and software systems of the SMuRF electronics, comparing achieved performance with science-driven design requirements. In particular, we focus on the case of large-channel-count, low-bandwidth applications, but the system has been easily reconfigured for high-bandwidth applications. The system described here has been successfully deployed in lab settings and field sites around the world and is baselined for use on upcoming large-scale observatories. [ABSTRACT FROM AUTHOR]

The BeamCal detector, one of the calorimeters in the forward region of the International Linear Collider detector, will serve three purposes: ensure hermeticity of the detector for small polar angles, reduce the backscattering from beamstrahlung electron-positron pairs into the detector center, and provide a low-latency signal for beam diagnostics. The BeamCal specifications in terms of noise suppression, signal charge, pulse rate, and occupancy pose unique challenges in the front end and readout electronics design. The Bean–BeamCal instrumentation IC is the integrated circuit under study to fulfill these requirements. To process the signal charge at the International Collider pulse rate, the Bean uses switched-capacitor filters and a slow reset-release technique. Each channel has a 10-bit successive approximation analog-to-digital converter. The Bean also features a fast feedback adder capable of providing a low latency output for beam diagnostic purposes. This work presents the design and characterization of a 3-channel prototype of the Bean built to validate concepts while the final device will comprise 32 channels. [ABSTRACT FROM PUBLISHER]

The ePix10ka2M (ePix10k) is a new large area detector specifically developed for X‐ray free‐electron laser (XFEL) applications. The hybrid pixel detector was developed at SLAC to provide a hard X‐ray area detector with a high dynamic range, running at the 120 Hz repetition rate of the Linac Coherent Light Source (LCLS). The ePix10k consists of 16 modules, each with 352 × 384 pixels of 100 µm × 100 µm distributed on four ASICs, resulting in a 2.16 megapixel detector, with a 16.5 cm × 16.5 cm active area and ∼80% coverage. The high dynamic range is achieved with three distinct gain settings (low, medium, high) as well as two auto‐ranging modes (high‐to‐low and medium‐to‐low). Here the three fixed gain modes are evaluated. The resulting dynamic range (from single photon counting to 10000 photons pixel−1 pulse−1 at 8 keV) makes it suitable for a large number of different XFEL experiments. The ePix10k replaces the large CSPAD in operation since 2011. The dimensions of the two detectors are similar, making the upgrade from CSPAD to ePix10k straightforward for most setups, with the ePix10k improving on experimental performance. The SLAC‐developed ePix cameras all utilize a similar platform, are tailored to target different experimental conditions and are designed to provide an upgrade path for future high‐repetition‐rate XFELs. Here the first measurements on this new ePix10k detector are presented and the performance under typical XFEL conditions evaluated during an LCLS X‐ray diffuse scattering experiment measuring the 9.5 keV X‐ray photons scattered from a thin liquid jet. [ABSTRACT FROM AUTHOR]

Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a new generation of cameras under development at SLAC, is introduced. [ABSTRACT FROM AUTHOR]

Abstract: The CSPAD-140k is a 140 kilopixel detector based on the Cornell-SLAC hybrid Pixel Array Detector (CSPAD) platform, developed around the CSPAD ASIC. Room temperature operation, 14bit on chip digitization with a purely digital data interface, and scaling modularity are some important characteristics that make this platform an effective choice for designing detector variants optimized for a range of experiments and applications. The CSPAD-140k has an active area of approximately 4×4cm2 and four ASICs, bundled in a small, inexpensive and easy-to-deploy package. Due to its versatility it has already been used successfully in several experiments at the CXI, XPP and XCS instruments at LCLS. This work also describes problems faced by scaling from a prototype system to a full size X-ray camera and presents the current status on the improvements achieved. [Copyright &y& Elsevier]