Spectroscopic-grade X-ray imaging up to 100 kHz frame rate with controlled-drift detectors

Controlled-drift detectors are fully depleted silicon detectors for X-ray imaging that combine good position resolution with very fast frame readout. The basic feature of the controlled-drift detector is the transport of the charge packets stored in each pixel column to the output electrode by means of a uniform drift field. The drift time of the charge packet identifies the pixel of incidence. Images of an X-ray source obtained with the controlled-drift detector up to 100-kHz frame rate are presented and discussed. The achievable energy resolution as a function of the operating temperature and frame rate is analyzed

Spectroscopic-Grade X-Ray Imaging up to 100-kHz Frame Rate With Controlled-Drift Detectors

Abstract-Controlled-drift detectors are fully depleted silicon detectors for X-ray imaging that combine good position resolution with very fast frame readout. The basic feature of the controlled-drift detector is the transport of the charge packets stored in each pixel column to the output electrode by means of a uniform drift field. The drift time of the charge packet identifies the pixel of incidence. Images of an X-ray source obtained with the controlled-drift detector up to 100-kHz frame rate are presented and discussed. The achievable energy resolution as a function of the operating temperature and frame rate is analyzed. Index Terms-Controlled-drift detector, fast readout, X-ray imaging

The ASTAROTH project

The most discussed topic in direct search for dark matter is arguably the verification of the DAMA claim. In fact, the observed annual modulation of the signal rate in an array of NaI(Tl) detectors can be interpreted as the awaited signature of dark matter interaction. Several experimental groups are currently engaged in the attempt to verify such a game-changing claim with the same target material. However, all present-day designs are based on a light readout via Photomultiplier Tubes, whose high noise makes it challenging to achieve a low background in the 1-6 keV energy region of the signal. Even harder it would be to break below 1 keV energy threshold, where a large fraction of the signal potentially awaits to be uncovered. ASTAROTH is an R\&D project to overcome these limitations by using Silicon Photomultipliers (SiPM) matrices to collect scintillation light from NaI(Tl). The all-active design based on cubic crystals is operating in the 87-150 K temperature range where SiPM noise can be even a hundred times lower with respect to PMTs. The cryostat was developed following an innovative design and is based on a copper chamber immersed in a liquid argon bath that can be instrumented as a veto detector. We have characterized separately the crystal and the SiPM response at low temperature and we have proceeded to the first operation of a NaI(Tl) crystal read by SiPM in cryogeny.Comment: proceedings of the LRT 2022 conferenc

Impact of detector parameters on Light Charged Particle identification through pulse-shape analysis

reserved2A. Castoldi; C. GuazzoniCastoldi, Andrea; Guazzoni, Chiar

EROIC: a BiCMOS pseudo-gaussian shaping amplifier for high-resolution X-ray spectroscopy

Abstract We present the design and complete characterization of a fifth-order pseudo-gaussian shaping amplifier with 1 ms shaping time. The circuit is optimized for the read-out of signals coming from Silicon Drift Detectors for highresolution X-ray spectroscopy. The novelty of the designed chip stands in the use of a current feedback loop to place the poles in the desired position on the s-plane. The amplifier has been designed in 0.8 mm BiCMOS technology and fully tested. The EROIC chip comprises also the peak stretcher, the peak detector, the output buffer to drive the external ADC and the pile-up rejection system. The circuit needs a single +5 V power supply and the dissipated power is 5 mW per channel. The digital outputs can be directly coupled to standard digital CMOS ICs. The measured integral-nonlinearity of the whole chip is below 0.05% and the achieved energy resolution at the Mn Ka line detected by a 5 mm 2 Peltier-cooled Silicon Drift Detector is 167 eV FWHM.