A micro-SPECT system having spatial resolution of 2.5 mm is presented. The system has a field of vision about 57 × 57 mm. Results of tomographic reconstruction of calibration phantoms using Tc-99m ...solution are outlined. The design of phantoms that can be used to assess performance of SPECT system having a narrow field of vision is given.
Deep Tracking for the SPD Experiment Rusov, D.; Goncharov, P.; Zhemchugov, A. ...
Physics of particles and nuclei letters,
10/2023, Volume:
20, Issue:
5
Journal Article
Peer reviewed
The SPD (Spin Physics Detector) is a planned spin physics experiment in the second interaction point of the NICA collider that is under construction at JINR. The data rate is expected to reach 0.2 ...Tbit/s at the maximum design luminosity, which requires fast tracking algorithms for online event filtration and offline reconstruction. The recurrent neural network model TrackNETv3, a deep learning analog of classical Kalman filter, has been developed recently and demonstrated good performance at the BM@N and BES-III experiments. The paper presents an application of the TrackNET model to the simulated data of the SPD tracker and preliminary results of the performance study.
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This paper describes the methodology and measurements results of the micro-SPECT system parameters with a 57 × 57 mm field of view. The system detection efficiency and uniformity of the Timepix ...based micro-SPECT system is measured using a
99m
Tc radioactive source. The system detection efficiency is 81%, while the total efficiency is 0.0038% only, mainly due to the small surface of the detector. The intrinsic uniformity is 92%. The integral and differential uniformity are 44 and 84%, respectively. The integral uniformity can be significantly improved by using additional filters and more advanced decoding algorithms that take into account the geometry of the collimator.
Investigation of the semiconductor detectors properties under neutron irradiation is very important for their practical application. High-resistivity gallium arsenide detectors (GaAs:Cr) were ...irradiated with various fast neutron fluences in range from 3.9×10n cm−2 to 3.7×1016 cm−2 at the IBR-2 reactor, FLNP, JINR. The neutron fluence was measured by placing silicon planar detectors at the measured points and measuring the 1 MeV (Si) equivalent fast neutron fluence. The charge collection efficiency and the current-voltage characteristics of irradiated detectors were measured, and their degradation after neutron irradiation was compared with the results obtained by irradiation with 21 MeV electrons.
A new design of a detector plane of sub-millimetre thickness for an electromagnetic sampling calorimeter is presented. It is intended to be used in the luminometers LumiCal and BeamCal in future ...linear e
+
e
-
collider experiments. The detector planes were produced utilising novel connectivity scheme technologies. They were installed in a compact prototype of the calorimeter and tested at DESY with an electron beam of energy 1–5 GeV. The performance of a prototype of a compact LumiCal comprising eight detector planes was studied. The effective Molière radius at 5 GeV was determined to be (8.1 ± 0.1 (stat) ± 0.3 (syst)) mm, a value well reproduced by the Monte Carlo (MC) simulation (8.4 ± 0.1) mm. The dependence of the effective Molière radius on the electron energy in the range 1–5 GeV was also studied. Good agreement was obtained between data and MC simulation.
A prototype of a luminometer, designed for a future
e
+
e
-
collider detector, and consisting at present of a four-plane module, was tested in the CERN PS accelerator T9 beam. The objective of this ...beam test was to demonstrate a multi-plane tungsten/silicon operation, to study the development of the electromagnetic shower and to compare it with MC simulations. The Molière radius has been determined to be 24.0 ± 0.6 (stat.) ± 1.5 (syst.) mm using a parametrization of the shower shape. Very good agreement was found between data and a detailed Geant4 simulation.
The scientific apparatus GAMMA-400 designed for study of electromagnetic and hadron components of cosmic rays will be launched to an elliptic orbit with the apogee of about 300 000 km and the perigee ...of about 500 km. Such a configuration of the orbit allows it to cross periodically the radiation belt and the outer part of magnetosphere. We discuss the possibility to use hybrid pixel detecters based on the Timepix chip and semiconductive sensors on board the GAMMA-400 apparatus. Due to high granularity of the sensor (pixel size is 55 mum) and possibility to measure independently an energy deposition in each pixel, such compact and lightweight detector could be a unique instrument for study of spatial, energy and time structure of electron and proton components of the radiation belt.
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