Marco Carminati

The ANDROMeDa project, recently funded by the Italian ministry of research with a 1M€ grant, aims to develop a novel light dark matter (DM) detector sensitive to DM-electron recoil in a target of vertically-aligned carbon nanotubes: the “dark-PMT”. Thanks to their vanishing density in the direction of the tube axis, carbon nanotubes allow a scattered electron to leave the target without being re-absorbed only if it travels parallel to the tubes. Therefore the detector is expected to have directional sensitivity, a key feature in DM searches. With only 1 g of exposure per year and a careful suppression of the backgrounds, such detector might achieve world-leading sensitivity for DM masses below 30 MeV.

Three-coil inductive power transfer is the state-of-the-art solution to power multiple miniaturised neural implants. However, the maximum delivered power is limited by the efficiency of the powering link and safety constrains. Here we propose a frequency-switching inductive link, where the passive resonator normally used in a three-coil link is replaced by an active resonator. It receives power from the external transmitter via a two-coil inductive link at the low frequency of 13.56 MHz. Then, it switches the operating frequency to the higher frequency of 433.92 MHz through a dedicated circuitry. Last, it transmits power to 1024 miniaturised implants via a three-coil inductive link using an array of 37 focusing resonators for a brain coverage of 163.84 mm . Our simulations reported a power transfer efficiency of 0.013% and a maximum power delivered to the load of 1970 μ under safety-constrains, which are …

The SIDDHARTA-2 collaboration at the INFN Laboratories of Frascati (LNF) aims to perform important measurements on kaonic atoms. In parallel to the groundbreaking kaonic deuterium measurement, presently running on the DA Φ NE collider at LNF, we plan to install additional detectors. The aim is to perform further kaonic atoms’ studies, taking advantage of the unique low energy and low momentum spread K− beam delivered by the at-rest decay of the ϕ meson. CdZnTe devices are ideal for detecting transitions toward both the upper and lower levels of intermediate-mass kaonic atoms, like kaonic carbon and aluminium. Measuring these transitions can have an important impact on the strangeness sector of nuclear physics. We present the results obtained in two preliminary tests conducted at DA Φ NE in view of measurements foreseen in 2024, with the twofold aim to tune the timing window required to reject …

Sterile neutrinos in the keV mass range present a viable candidate for dark matter. They can be detected through single decay, where they cause small spectral distortions. The Karlsruhe Tritium Neutrino (KATRIN) experiment aims to search for keV-scale sterile neutrinos with high sensitivity. To achieve this, the KATRIN beamline will be equipped with a novel multi-pixel silicon drift detector focal plane array named TRISTAN. In this study, we present the performance of a TRISTAN detector module, a component of the eventual 9-module system. Our investigation encompasses spectroscopic aspects such as noise performance, energy resolution, linearity, and stability.

Gamma-ray astronomy explores a wide range of photon energies (0.1 MeV–1 PeV) and leverages different types of detectors, based on different technologies and coping with a variety of installation constraints, spanning from ground to satellite telescopes. Common aspects across instrumentation are a multiplicity of channels and very weak signals, often requiring photodetectors with internal gain such as photomultiplier tubes (PMTs) and silicon photomultipliers (SiPMs). Here we review the key concepts in the design of the readout electronics, with special focus on the latter class of solid-state detectors and on modern integrated microelectronic implementations, allowing unprecedented miniaturization. The different strategies in the readout of signals (voltage, charge and current mode, negative and positive feedback circuits) are compared and illustrated with reference to the most relevant literature.

The most important information still missing in the field of the low-energy antikaon-nucleon inter actions studies is the experimental determination of the hadronic energy shift and width of kaonic deuterium. This measurement will be performed by the SIDDHARTA-2 experiment, installed at the DAΦNE collider and presently in data taking campaign. The precise measurement of the shift and width of the 1s level with respect to the purely electromagnetic calculated values, generated by the presence of the strong interaction, through the measurement of the X-ray transitions to this level, in kaonic hydrogen, was performed by the SIDDHARTA collaboration, the kaonic deuterium is underway by SIDDHARTA-2. These measurement will allow the first precise experimental extraction of the isospin dependent antikaon-nucleon scattering lengths, funda mental quantities for understanding low-energy QCD in the strangeness …

The aim of the SIDDHARTA-2 experiment is to perform the first measurement ever of the width and shift induced by the strong interaction to the 2p→1s energy transition of kaonic deuterium. This ambitious goal implies a challenging task due to the very low X-ray yield of kaonic deuterium, which is why an accurate and thorough characterization of the experimental apparatus is mandatory before starting the data-taking campaign. Helium-4 is an excellent candidate for this characterization since it exhibits a high yield in particular for the 3d→2p transition, roughly 100 times greater than that of the kaonic deuterium. The ultimate goal of the work reported in this paper is to study the performances of the full experimental setup in view of the kaonic deuterium measurement. This is carried out by measuring the values of the shift and the width for the 3d→2p energy transition of kaonic helium-4, induced by the strong interaction. The values obtained for these quantities, for a total integrated luminosity of ∼31/pb, are ε2p=2.0±1.2(stat)±1.5(syst)eV and Γ2p=1.9±5.7(stat)±0.7(syst)eV. The results, compared to the value of the shift measured by the SIDDHARTA experiment ε2p=0±6(stat)±2(syst)eV, show a net enhancement of the resolution of the apparatus, providing strong evidence of the potential to perform the challenging measurement of the kaonic deuterium.

KAMEO (Kaonic Atoms Measuring Nuclear Resonance Effects Ob-servables) is a proposal for an experiment aiming to perform the first consistent measurement of the E2 nuclear resonance effects in kaonic molybdenum A=94,96,98,100 isotopes. The E2 nuclear resonance mixes atomic states, due to the electrical quadrupole excitation of nuclear rotational states. It occurs in atoms having the energy of a nuclear excitation state closely matching an atomic de-excitation state energy, and affects the rates of X-ray atomic transitions matching the energy of the resonance. The measurement E2 nuclear resonance effect in KMO isotopes allows the study of the strong kaon-nucleus interaction in a rotational excited nuclear state. Moreover, the effect enables the K- to access an inner atomic level not easily reachable by the kaon normal cascade, due to the nuclear absorption. The KAMEO proposed apparatus consists of 4 …

In this paper we present the results of a new kaonic helium-4 measurement with a 1.37 gl− 1 gaseous target by the SIDDHARTA-2 experiment at the DAΦNE collider. We measured, for the first time, the energies and yields of three transitions belonging to the M-series. Moreover, we improved by a factor about three, the statistical precision of the 2p level energy shift and width induced by the strong interaction, obtaining the most precise measurement for gaseous kaonic helium, and measured the yield of the L α transition at the employed density, providing a new experimental input to investigate the density dependence of kaonic atoms transitions yield.

This article presents the results of the kaonic helium-4 measurement conducted by the SIDDHARTA-2 experiment, aiming to provide crucial insights into the low-energy strong interaction in the strangeness sector. High-precision X-ray spectroscopy is used to examine the interaction between negatively charged kaons and nuclei in atomic systems. The SIDDHARTA-2 setup was optimized through the kaonic helium-4 measurement in preparation for the challenging kaonic deuterium measurement. The kaonic helium-4 measurement at a new density of 2.25 g/l is reported, providing the absolute and relative yields for the L-series transitions, which are essential data for understanding kaonic atom cascade processes.

THE IEEE International Symposium on Circuits and Sys-tems (ISCAS) is the flagship conference of the IEEE Circuits and Systems (CAS) Society and the world’s premiere forum for researchers in the fields of theory, design and implementation of circuits and systems. The IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS (TBioCAS) highlights selected papers from ISCAS on topics related to biological and healthcare applications. This special section features three selected papers from ISCAS 2023, held in Monterey, California, USA from May 21 to 25, 2023.The ISCAS 2023 technical committee invited original work in all areas of circuits and systems, including topics such as circuits and systems for analog, mixed-signal, digital, power/energy, sensory, communication, and biomedical applications, as well as digital signal processing and intelligent sensors and systems. The TBioCAS received a total …

Boron neutron capture therapy exploits 10 B (n, α) 7 Li reactions for targeted tumor destruction. In this work, we aimed at developing a dose monitoring system based on the detection of 478 keV gamma rays emitted by the reactions, which is very challenging due to the severe background present. To this aim, we proposed a compact gamma-ray detector with a pinhole collimator and shielding housing. Experimental measurements at Pavia University’s nuclear reactor involved varying boron concentrations and artificial shifts of the sources. The system successfully resolved the 478 keV photopeak and detected 1 cm lateral displacements, confirming its suitability for precise boron dose monitoring.

Embedding signal processing in the front-end of radiation detectors represents an approach to cope with the growing complexity of nuclear imaging scanners with increasing field of view (i.e. higher number of channels). Machine learning (ML) offers a good compromise between intrinsic image reconstruction performance and computational power. While most hardware accelerators for ML are based on digital circuits and, thus, require the analog-to-digital conversion of all individual signals from photodetectors, an analog approach allows to streamline the pipeline. We present the study of an analog accelerator implementing a neural network (NN) with 42 neurons in a 0.35 μm CMOS process node. The specific target is the reconstruction of the position of interaction of gamma-rays in the scintillator crystal of Anger cameras used for PET and SPECT. This chip can be used stand-alone or monolithically integrated …

This work provides the first experimental proof of an increased neutron capture photon signal following the introduction of boron to a PMMA phantom during helium and carbon ion therapies in Neutron Capture Enhanced Particle Therapy (NCEPT). NCEPT leverages B neutron capture, leading to the emission of detectable 478 keV photons. Experiments were performed at the Heavy Ion Medical Accelerator in Chiba, Japan, with two Poly(methyl methacrylate) (PMMA) targets, one bearing a boron insert. The BeNEdiCTE gamma-ray detector measured an increase in the 478 keV signal of 45 ± 7% and 26 ± 2% for carbon and helium ion irradiation, respectively. Our Geant4 Monte Carlo simulation model, developed to investigate photon origins, found less than 30% of detected photons originated from the insert, while boron in the detector’s circuit boards contributed over 65%. Further, the model investigated detector …

A newly introduced laboratory experience addressing the practical understanding of the impedance of the non-Faradaic electrochemical interface, within a bioelectronics class, is presented. The project is carried out by teams of M.Sc. students (3 to 5 persons) of mixed backgrounds (electronics and biomedical engineering). It comprises two phases. First, a design phase, in which a PCB hosting planar gold coated electrodes, to be sized in order to properly measure the ionic resistance of the solution (below 10 MHz), and a low-noise transimpedance stage to interface to a USB network analyzer are designed. Then, during the experimental activity impedance spectroscopy is performed with the electrodes in saline solution, coupled to microfluidics, and data are analyzed to estimate the solution conductivity and compared with simulations.

Purpose: In-vivo range verification has been a hot topic in particle therapy since two decades. Many efforts have been done for proton therapy, while fewer studies were conducted considering a beam of carbon ions. In the present work, a simulation study was performed to show whether it is possible to measure the prompt-gamma fall-off inside the high neutron background typical of carbon-ion irradiation, using a knife-edge slit camera. In addition to this, we wanted to estimate the uncertainty in retrieving the particle range in the case of a pencil beam of C-ions at clinically relevant energy of 150 M e V u. Methods: For these purposes, the Monte Carlo code FLUKA was adopted for simulations and three different analytical methods were implemented to get the accuracy in the range retrieval of the simulated set-up. Results: The analysis of simulation data has brought to the promising and desired precision of about 4 …

We present the development of a new 16-channel SDD-based X-ray detector with a backscattering geometry, called ASCANIO, designed for experiments in synchrotron beamlines.The main objective of this research project, supported by DESY (Germany), is to improve the quality of X-ray Fluorescence Microscopy (XFM) experiments providing a larger throughput of events. The detection module consists of four monolithic SDDs, each with four channels, and a thickness of 1 mm to provide a high absorption efficiency of 65% at 20 keV. ASCANIO is optimised to maximise photon collection by having a solid angle of 1 sr with 8 mm between the sample and the window. To ensure count-rate capabilities higher than 20 Mcps, it implements an innovative tilted SDD geometry that provides a uniform distribution of fluorescence light among channels. The low-noise analog read-out assures good energy resolution of 129 eV …

We present an evaluation of the maximum throughput of ARDESIA-16 at varying Input Count Rates using three different Digital Pulse Processors: XGLab's DANTE, XIA LLC's FalconX8, and a modified version of CAEN S.p.A.'s DT5560SE digitizer. We will cover performance metrics such as Output Count Rate and energy resolution, defined as the FWHM of the Mn-Kα peak. These measurements are specifically optimized to achieve a reasonable compromise between a satisfactory energy resolution and a high count rate with low dead time.The aim of this work is to study the performance of ARDESIA-16 with various Digital Pulse Processors at high input rates in order to cope with the quest for ultra-high-rate detectors required by next-generations synchrotron beamlines.

In the field of hadrontherapy, it is demonstrated that the Prompt Gamma (PG) measurements are strongly affected by the presence of a neutron background, which can limit the possibility to perform range monitoring, especially in the framework of Carbon ion therapy. This work is a first step towards the implementation of the Pulse Shape Discrimination (PSD) technique for neutron background reduction in PGI. A statistical analysis has been developed, that is intended to model the performances of a detection system based on the CLYC scintillator in performing Pulse Shape Discrimination, and a Figure Of Merit (FOM) of this detector is evaluated with respect to several parameters. This analysis serves the aim of deducing the optimal parameters to perform PSD, without having to carry out multiple experimental measures, and to assess if the obtained performances are sufficient to effectively perform neutron/gamma …

The E2 nuclear resonance effect is a phenomenon that occurs when the energy of an atomic de-excitation state closely matches that of a nuclear excitation state, resulting in the attenuation of certain atomic X-ray lines in the resonant isotope target. The study of this effect in kaonic atoms can provide important insight into the mechanisms of the strong kaon-nucleus interaction. In 1975, Goldfrey, Lum, and Wiegand at Lawrence Berkeley Laboratory observed the effect in 98 42Mo, but they did not have enough data to reach a conclusive result. The E2 nuclear resonance effect is expected to occur in four kaonic molybdenum isotopes (94 42Mo, 96 42Mo, 98 42Mo, and 100 42 Mo) with similar energy values. The KAMEO (Kaonic Atoms Measuring Nuclear Resonance Effects Observables) proposal plans to study this effect in these isotopes at the DAΦNE Φ factory during the SIDDHARTA-2 experiment. KAMEO will use four solid strip targets, each enriched with a different molybdenum isotope, and expose them to negatively charged kaons produced by Φ meson decays. The X-ray transition measurements will be performed using a high-purity germanium detector, and an additional solid strip target of non-resonant 92 42Mo isotope will be exposed and used as a reference for standard non-resonant transitions.