The ORION chipset constellation for THESEUS Space Mission Concept
The research focuses on the design of a low-power low-noise distributed readout chain for the X-Gamma Imaging Spectrometer (XGIS) on-board the THESEUS space mission concept.
The Transient High Energy Sky and Early Universe Surveyor (THESEUS) is a M-class space mission concept that has been selected by the European Space Agency (ESA) for Phase 0/A study within the Cosmic Vision program, in view of lunch opportunity in 2032. The main scientific objectives of the THESEUS mission, are to explore the early universe from 1 Billion years to 400 Million years since the Big Bang by realizing a comprehensive census of Gamma-Ray Bursts (GRBs) with a special focus on high redshift GRBs and to perform deep monitoring of the X-ray transients in the new-coming era of multi-messenger astrophysics in support of Gravitational Wave (GW) detectors.
The ORION chipset, a full-custom multi-chip Application Specific Integrated Circuit (ASIC) realized for the readout and signal processing of the X-Gamma Imaging Spectrometer (XGIS) on-board the THESEUS space mission, is beign designed by the SDIC-Lab. Based on a wide dynamic range double detection mechanism, the XGIS camera is arranged in a matrix of 10×10 detection modules, each one composed by 64 CsI(Tl) scintillation bars optically coupled at the top and bottom extremities to two 8×8 monolithic Silicon Drift Detector matrices.
LYRA ASIC for the HERMES Scientific Pathfinder
The overall main scientific goal of the HERMES project is to provide a system able to detect and accurately localize GRBs and other high-energy transients, such as the counterparts of GW events (merging of compact objects, supernovae, or other unknown heavenly events), that can be deployed in a few years, bridging the gap between the aging, past generation of X-ray monitors (Swift, INTEGRAL, Agile and Fermi) and the next ones. Past experience (BeppoSAX, HETE2, Swift, Integral) shows that arcmin localization is key to uniquely localize the galaxy hosting the transient at all redshifts. Arcmin localization of most GRBs with flux larger than a few photons/cm2/s is therefore the final goal of the HERMES project.
The SDIC-Lab realized an ASIC, called LYRA, specifically designed for the HERMES project detect and localize high-energy rapid transient events up to 2.2 MeV. The detection system is a combination of Gadolinium Aluminum Gallium Garnet (GAGG) scintillators for high-energy photons coupled to Silicon Drift Detectors (SDD) used also for direct detection of low energy photons. The readout electronics has been organized in a multi-chip architecture: 30 LYRA Front-End (LYRA-FE) placed close to the anode of the SDDs; they send their pre processed signals, in current mode, to a 32-channel LYRA Back-End chip (LYRA-BE) where the signal is filtered and processed.
The RIGIEL pixel readout cell for high-throughput X-ray astrophysics
The RIGEL ASIC has been designed within the PixDD (Pixel Drift Detector) project to be bump-bonded to a novel pixelated SDD, with the goal of performing spectral and timing studies of low-flux compact cosmic sources. The ASIC is based on a 16 × 16 matrix of 300 µm × 300 µm front-end cells, each including a preamplifier, bump-bonded to a pixel of the PixDD detector, a pulse shaper, a peak stretcher, an output buffer, a current-mode amplitude discriminator, a voltage-mode peak discriminator, as well as a reset and pileup rejection logic. Moreover, the RIGEL ASIC includes a configuration memory, which stores the programmable parameters for the device, a local trigger logic (LTL), which handles the trigger signals generated by the front-end cells for self triggered operation, and 16 Wilkinson (single ramp) 10-bit ADCs (one for each row of the matrix).
SIRIO for high energy resolution X-ray spectroscopy at the ELETTRA and SESAME synchrotrons
SIRIO is a state-of-the-art charge sensitive preamplifier, which works in pulsed reset mode, for the readout of charge signals coming from semiconductor detectors. With an minimum noise performance, the SIRIO preamplifier is suitable for high-performance spectroscopic systems, capable of achieving an intrinsic equivalent noise charge (ENC) below 1 electron r.m.s., and allowing an optimum energy resolution of 122.7 eV full-width at half maximum (FWHM) at moderate cooling. As part of the INFN-ReDSoX project, the SIRIO CSA is currently being integrated into two newly designed detection systems dedicated to the TwinMic beamline at the Elettra synchrotron in Trieste (Italy) – for Low-Energy X-Ray Fluorescence (LEXRF) applications – and to the XAFS beamline at the SESAME synchrotron in Allan (Jordan). SIRIO demonstrated also an excellent performance in combination with room temperature detectors, such as CdTe and SiC detectors.