arXiv subjects

R. Gadea

Publications and source records attributed to R. Gadea.

5 recordsLinked to original sources

arXiv2024

Evaluation of Coincidence Time Resolution in a liquid xenon detector with silicon photomultipliers

This work explores the combination of liquid xenon as a scintillating medium and silicon photomultipliers as a readout in Positron Emission Tomography (PET) for enhanced Time-Of-Flight resolution. We present the results of our first prototype optimized to maximize light collection using high-PDE, VUV-sensitive sensors and to minimize time fluctuations. We report a coincidence time resolution of 281 $\pm$ 2 ps FWHM, obtained using a $^{22}$Na calibration source. This result is competitive with the current state-of-the-art PET scanners and represents a significant step forward in the development of liquid xenon as a viable alternative to conventional scintillators in PET technology.

physics.ins-det↗

arXiv2022

Measurement of the scintillation resolution in liquid xenon and its impact for future segmented calorimeters

We report on a new measurement of the energy resolution that can be attained in liquid xenon when recording only the scintillation light. Our setup is optimized to maximize light collection, and uses state-of-the-art, high-PDE, VUV-sensitive silicon photomultipliers. We find a value of 3.7 $\pm$ 0.4% at 511 keV, once saturation effects are corrected for, a result close to the Poissonian resolution that we expect in our setup (2.8 $\pm$ 0.4% $\sigma$ at 511 keV). Our results in the intrinsic resolution (2.3 $\pm$ 0.8 %) are compatible, within errors, at 511 keV, with those found by theoretical estimations which have been standing for the last twenty years, 1.8%. Our work opens new possibilities for apparatus based on liquid xenon and using scintillation only. In particular it suggests that modular scintillation detectors using liquid xenon can be very competitive as building blocks in segmented calorimeters, with applications to Positron Emission Tomography technology.

physics.ins-det↗

arXiv2021

Monte Carlo characterization of PETALO, a full-body liquid xenon-based PET detector

New detector approaches in Positron Emission Tomography imaging will play an important role in reducing costs, lowering administered radiation doses, and improving overall performance. PETALO employs liquid xenon as the active scintillating medium and UV-sensitive silicon photomultipliers for scintillation readout. The scintillation time in liquid xenon is fast enough to register time-of-flight information for each detected coincidence, and sufficient scintillation is produced with low enough fluctuations to obtain good energy resolution. The present simulation study examines a full-body-sized PETALO detector and evaluates its potential performance in PET image reconstruction.

physics.ins-det↗

arXiv2021

PETALO read-out: A novel approach for data acquisition systems in PET applications

PETALO (a Positron Emission Tof Apparatus based on Liquid xenOn) is a new approach for Positron Emission Tomography scanners, based on liquid xenon. The PETALO detector aims at capturing the light produced by the scintillation in LXe taking advantage of its uniform response and continuity. This strategy will lead to a geometrical distortion free behavior compared to other PET detectors. To this end, the sensors chosen for the light readout are SiPMs, which provide large area, high gain and very low noise. In order to take advantage of the unique PETALO detector characteristics a read-out architecture must be designed to meet the following specifications: Electronics associated to detector (front-end and read-out itself) must be fully expandable in terms of detector size. Read-out scheme must be compatible with the non-segmented structure of the detector. Time of Flight (TOF) capabilities must be assured at the scanner level, that is to say front-end and read-out electronics should not degrade LXe time performance. In these proceedings, a new readout concept is introduced which is compatible with a fully continuous medium detector such as PETALO. Results show that the system is feasible, with the introduction of a fast compression technique to further reduce the data bandwidth requirements.

physics.ins-det↗

arXiv2020

Processing of Compton events in the PETALO readout system

PETALO (Positron Emission TOF Apparatus based on Liquid xenOn) exploits the unique characteristics of liquid xenon as a scintillator for use in a PET detector. Here initial simulation studies are detailed which highlight the potential of such a detector and outline the steps taken in the reconstruction of 511 keV gamma rays and in the full PET image reconstruction. In particular, a neural network-based approach is conceived in order to tag gamma rays that are poorly reconstructed due to Compton scattering. It is found that though a significant fraction of events undergo Compton scattering, not all of these events will necessarily be poorly reconstructed. Further study is necessary to determine whether or not an online implementation of the neural network-based event tagging will provide sufficient recovery of the image quality.

physics.ins-det↗