21 research outputs found
On-chip fully reconfigurable Artificial Neural Network in 16 nm FinFET for Positron Emission Tomography
Smarty is a fully-reconfigurable on-chip feed-forward artificial neural
network (ANN) with ten integrated time-to-digital converters (TDCs) designed in
a 16 nm FinFET CMOS technology node. The integration of TDCs together with an
ANN aims to reduce system complexity and minimize data throughput requirements
in positron emission tomography (PET) applications. The TDCs have an average
LSB of 53.5 ps. The ANN is fully reconfigurable, the user being able to change
its topology as desired within a set of constraints. The chip can execute 363
MOPS with a maximum power consumption of 1.9 mW, for an efficiency of 190
GOPS/W. The system performance was tested in a coincidence measurement setup
interfacing Smarty with two groups of five 4 mm x 4 mm analog silicon
photomultipliers (A-SiPMs) used as inputs for the TDCs. The ANN successfully
distinguished between six different positions of a radioactive source placed
between the two photodetector arrays by solely using the TDC timestamps.Comment: 13 pages, 24 Figure
A monolithic ASIC demonstrator for the Thin Time-of-Flight PET scanner
Time-of-flight measurement is an important advancement in PET scanners to
improve image reconstruction with a lower delivered radiation dose. This
article describes the monolithic ASIC for the TT-PET project, a novel idea for
a high-precision PET scanner for small animals. The chip uses a SiGe Bi-CMOS
process for timing measurements, integrating a fully-depleted pixel matrix with
a low-power BJT-based front-end per channel, integrated on the same 100 thick die. The target timing resolution is 30 ps RMS for electrons from the
conversion of 511 keV photons. A novel synchronization scheme using a
patent-pending TDC is used to allow the synchronization of 1.6 million channels
across almost 2000 different chips at picosecond-level. A full-featured
demonstrator chip with a 3x10 matrix of 500x500 pixels was
produced to validate each block. Its design and experimental results are
presented here
Characterization of the demonstrator of the fast silicon monolithic ASIC for the TT-PET project
The TT-PET collaboration is developing a small animal TOF-PET scanner based
on monolithic silicon pixel sensors in SiGe BiCMOS technology. The demonstrator
chip, a small-scale version of the final detector ASIC, consists of a 3 x 10
pixel matrix integrated with the front-end, a 50 ps binning TDC and read out
logic. The chip, thinned down to 100 {\mu}m and backside metallized, was
operated at a voltage of 180 V. The tests on a beam line of minimum ionizing
particles show a detection efficiency greater than 99.9 % and a time resolution
down to 110 ps
Feasibility study of an active target for the MEG experiment
We consider the possibility to have an active target for the upgrade of the MEG experiment (MEG II). The active target should work as (1) a beam monitoring, to continuously measure the muon stopping rate and therefore provide a direct evaluation of the detector acceptance (or an absolute normalization of the stopped muon); and as (2) an auxiliary device for the spectrometer, to improve the determination of the muon decay vertex and consequently to achieve a better positron momentum and angular resolutions, detecting the positron from the muon decay. In this work we studied the feasibility of detecting minimum ionizing particle with a single layer of 250 ÎĽm fiber and the capability to discriminate between the signal induced by either a muon or a positron
A simulation tool for scintillating fibers coupled to SiPM for MIP and heavy ionizing particle identification
The MEG experiment searches for the ÎĽ+e+Îł decay by stopping on a thin passive target the most intense continuous muon beam in the world. We are studying the possibility to have an active target, which should continuously monitor the muon beam and provide a precise measurement of the decay vertex, complementing the new spectrometer. The detector is based on thin scintillating fibers coupled to silicon photomultipliers (SiPMs), exploiting their insensitivity to the magnetic field, competitive PDE with respect to nominal PMT QE and low HV supply.This device can be used as a stand alone tool. In this paper we present a Monte Carlo simulation for a single fiber coupled to SiPM in order to study the propagation of the photons through the fiber and the response of the SiPM