2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)最新文献

First Principle Defect Analysis in 150 µm 4H-SiC Epitaxial Layer Schottky Barrier Detectors 150µm 4H-SiC外延层肖特基势垒探测器的第一原理缺陷分析

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9507936

Joshua W. Kleppinger, S. Chaudhuri, Omerfaruk Karadavut, K. Mandal

{"title":"First Principle Defect Analysis in 150 µm 4H-SiC Epitaxial Layer Schottky Barrier Detectors","authors":"Joshua W. Kleppinger, S. Chaudhuri, Omerfaruk Karadavut, K. Mandal","doi":"10.1109/NSS/MIC42677.2020.9507936","DOIUrl":"https://doi.org/10.1109/NSS/MIC42677.2020.9507936","url":null,"abstract":"High resolution Schottky barrier detectors (SBDs) were fabricated on 150 µm thick 4H-SiC epilayers using a proprietary device design. Electrical properties of the SBD junctions were characterized by temperature-dependent current-voltage (I-V- T) measurements which showed ultra-low leakage current densities lower than 100 pA cm−2at -150 V and remained below 1 µ A.cm−2 even at 600K. Electrically active deep levels present in the epilayers were identified and characterized by deep level transient spectroscopy (DLTS) which showed the presence of three deep levels - Ti(c), Z1/2 and EH6/7- with low concentrations (~1011 cm−3). The energy levels were investigated theoretically by density functional theory (DFT) calculations on intrinsic vacancies and titanium point defects. Pulse height spectra (PHS) were collected using a 241Am alpha source and a percentage energy resolution of 0.55% at 5486 keV was obtained. Further analysis of the forward bias I-V- T showed an improvement in ideality factor and barrier height at elevated temperature revealing the improvement of detection performance at higher temperature.","PeriodicalId":6760,"journal":{"name":"2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"4 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2020-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73527197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

ALTIROC 1, a 25 ps time resolution ASIC for the ATLAS High Granularity Timing Detector ALTIROC 1，用于ATLAS高粒度定时检测器的25 ps时间分辨率ASIC

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9507972

C. Agapopoulou, P. Dinaucourt, A. Dragone, D. Gong, C. de La Taille, N. Makovec, B. Markovic, G. Martin-Chassard, C. Milke, M. Morenas, L. Ruckman, S. Sacerdoti, A. Schwartzman, N. Seguin-Moreau, L. Serin, D. Su, J. Ye

{"title":"ALTIROC 1, a 25 ps time resolution ASIC for the ATLAS High Granularity Timing Detector","authors":"C. Agapopoulou, P. Dinaucourt, A. Dragone, D. Gong, C. de La Taille, N. Makovec, B. Markovic, G. Martin-Chassard, C. Milke, M. Morenas, L. Ruckman, S. Sacerdoti, A. Schwartzman, N. Seguin-Moreau, L. Serin, D. Su, J. Ye","doi":"10.1109/NSS/MIC42677.2020.9507972","DOIUrl":"https://doi.org/10.1109/NSS/MIC42677.2020.9507972","url":null,"abstract":"1 Abstract—Designed and characterized by the HGTD collaboration, ALTIROC belongs to the family of readout ASICs used at the Large Hadron Collider (LHC) for the High Luminosity-LHC upgrade. ALTIROC1 is a 25-channel ASIC designed in CMOS 130 nm to read out the 5 x 5 matrix of 1.3 mm x 1.3 mm Low Gain Avalanche Diodes (LGAD) of the ATLAS HGTD detector. The targeted combined time resolution of the sensor and its readout electronics from 35 ps/hit (initial) to 70 ps/hit (end of operational lifetime). Each ASIC channel integrates an RF preamplifier followed by a high speed discriminator and two TDCs for Time-of-Arrival and Time-Over-Threshold measurements as well as a local memory. This front-end must exhibit an extremely low jitter noise while keeping a challenging power consumption of less than 4.5 mW per channel. This conference proceeding summarizes the ASIC's architecture, its measured performances compared to simulation, along with the requirements for the HEP experiments.","PeriodicalId":6760,"journal":{"name":"2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"10 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2020-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74526313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Deconvolving Plastic Scintillator Gamma-Ray Spectra Using Particle Swarm Optimization 基于粒子群优化的塑料闪烁体伽玛射线谱解卷积

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9507902

A. Proctor

{"title":"Deconvolving Plastic Scintillator Gamma-Ray Spectra Using Particle Swarm Optimization","authors":"A. Proctor","doi":"10.1109/NSS/MIC42677.2020.9507902","DOIUrl":"https://doi.org/10.1109/NSS/MIC42677.2020.9507902","url":null,"abstract":"Plastic scintillators made from Polyvinyl Toluene 1(PVT) doped with fluorescent dye are used extensively in homeland security, scrap metal inspections, and other applications that require a large-area, cost-effective gamma detector. Unfortunately, gamma ray detection with PVT results in only Compton-edge events which contribute to a broad continuum spectrum having no discernible features. Other methods of obtaining information from low resolution PVT spectra have been described in publications but at the present time there is no practical method suitable for routine use. We have developed a method based on Particle Swarm Optimization (PSO) which analyzes raw PVT spectra and provides a histogram of contribution(s) vs. incident monoenergetic gamma energy(s). This is accomplished by summing multiple single-energy calculated PVT gamma responses into a ‘spectrum’ until a ‘best fit’ to the original raw data spectrum is obtained. The input set of response functions are calculated using MCNP5 and cover an appropriate energy range; we use a set of 255 response functions with 11 keV spacing between them (this corresponds to the ADC gain used in our PVT detectors). This set provides a range of 11 keV to 2805 keV for incident monoenergetic gamma energies which is suitable for most applications. Usually, we find that only one or two gamma response functions contribute to a ‘peak’ in the calculated histogram. Traditional radionuclide identification methods can be applied once the contribution gamma energies have been identified. As an added benefit: locating natural background gamma rays: 238 keV, 609 keV, 1460 keV, and 2614 keV in the deconvolved spectrum can be used to gain-stabilize the PVT detector.","PeriodicalId":6760,"journal":{"name":"2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"80 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2020-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74591751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Assessment of the Non-Linear Response of DEPFET Sensors with Signal Compression 信号压缩下DEPFET传感器非线性响应的评估

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9508034

A. Castoldi, C. Guazzoni, S. Aschauer, L. Strüder, K. Hansen, S. Maffessanti, M. Porro

引用次数: 0

Time-of-Flight Spectroscopy of 252Cf Spontaneous Fission Neutrons: Influences of Detector Voltage, Pulse-Shape Discrimination and Shielding 252Cf自发裂变中子的飞行时间光谱:探测器电压、脉冲形状判别和屏蔽的影响

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9507768

Alex Grievson, C. J. Taylor, N. Roberts, M. Bunce, M. Joyce

引用次数: 0

Neural Network-based Inter-crystal Scatter Event Positioning in a PET System Design Based on 3D Position Sensitive Detectors 基于三维位置敏感探测器的PET系统设计中基于神经网络的晶体间散射事件定位

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9507821

C. Wu, M. S. Lee, C. Levin

{"title":"Neural Network-based Inter-crystal Scatter Event Positioning in a PET System Design Based on 3D Position Sensitive Detectors","authors":"C. Wu, M. S. Lee, C. Levin","doi":"10.1109/NSS/MIC42677.2020.9507821","DOIUrl":"https://doi.org/10.1109/NSS/MIC42677.2020.9507821","url":null,"abstract":"We demonstrate a simulation-based proof-of-concept for superior inter-crystal scatter (ICS) event positioning using a feed-forward neural network (NN) architecture compared to traditional winner-takes-all (WTA) and loser-takes-all (LTA) algorithms. Using a GATE Monte Carlo simulation of a 3D position-sensitive scintillation detector module comprising long crystals read out from the side using SiPMs with 3×3×3 mm3 effective detector voxels, we observe NN ICS event positioning accuracies of 0.753 to 0.680 when the number of interactions per annihilation photon ranges from 2 to 5: significantly more robust compared to 0.726 to 0.367 for LTA and 0.613 to 0.251 for WTA methods over the same range. We then scale the single-detector simulation into a 25 cm diameter PET brain imaging system and reconstruct contrast and resolution phantoms for image quality analysis. The NN model outperformed both WTA and LTA, with image normalized Mean Absolute Errors of 0.030 and 0.122 for contrast and resolution phantoms compared to 0.046, 0.178 and 0.034, 0.140 for WTA and LTA. The NN demonstrated 6.04 to 8.95% higher Contrast Recovery (from resolution phantom), 0.53 to 2.85% larger Contrast Noise Ratio (from contrast phantom), and 2.13 to 6.34% higher Modulation Transfer Function values (from resolution phantom) compared to LTA, which performed second-best. The upper bound for these NN relative improvements occurred with features near the spatial resolution limit of the simulated system (2 mm). Our results indicate the NN positioning approach we examined improves most image quality and quantitation figures of merit.","PeriodicalId":6760,"journal":{"name":"2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"33 4","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2020-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72584041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Interface for Exchanging Geometric Parameters in Geant4 Based Particle Therapy Simulation Framework 基于Geant4的粒子治疗仿真框架中几何参数交换的接口

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9507843

T. Aso, C. Omachi, T. Toshito, T. Sasaki

{"title":"Interface for Exchanging Geometric Parameters in Geant4 Based Particle Therapy Simulation Framework","authors":"T. Aso, C. Omachi, T. Toshito, T. Sasaki","doi":"10.1109/NSS/MIC42677.2020.9507843","DOIUrl":"https://doi.org/10.1109/NSS/MIC42677.2020.9507843","url":null,"abstract":"The particle therapy system simulation framework (PTSIM) is a Geant4 based Monte Carlo simulation software developed for radiation therapy. It has been continuously extending the functions to facilitate advanced researches in medical physics domain. Consequently, the PTSIM is used in many facilities for verification of treatment plans and quality assurances. In the PTSIM, various types of beam devices are provided as software components named “beam-modules”. The geometry is constructed using a class of the beam-module and the detail geometric parameters in the ASCII data format. This strategy contributed that allows the PTSIM users to easily find the beam-module from the categorized types of beam devices and to develop a rapid prototyping of treatment port in the simulation. However, radiation therapy facilities may introduce variants of existing beam-modules, that may require the implementation of a new class for the beam-module in the PTSIM. In order to respond to such requirements without any coding effort, the interface for the Geometry Description Markup Language (GDML) has been introduced in the PTSIM. The GDML is a specialized XML-based language for an application-independent persistent format. Therefore, it can describe a user-defined complex geometry and exchanging the geometry data file among different facilities. In addition, for the purpose of examining complex geometries, a new interface for the ParaView visualization software has been developed. The interface converts the geometry in the PTSIM to the structured points data in the VTK legacy format. This paper reports on the implementations and the usages of GDML and ParaView interfaces in the PTSIM.","PeriodicalId":6760,"journal":{"name":"2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"80 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2020-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78219114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Influence of Laser Surface Treatment on Properties of CdTe X- and γ-ray Detectors 激光表面处理对CdTe X射线和γ射线探测器性能的影响

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9507823

O. Maslyanchuk, V. Strebezhev, P. Fochuk, I. Fodchuk, M. Solovan, M. Sorokatyi, I. Boledzyuk, R. James

引用次数: 0

Multiple PET Reconstruction Assisted Non-local Mean Denoising of PET Images 多重PET重构辅助PET图像非局部均值去噪

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9507772

Hossein ARABI, H. Zaidi

{"title":"Multiple PET Reconstruction Assisted Non-local Mean Denoising of PET Images","authors":"Hossein ARABI, H. Zaidi","doi":"10.1109/NSS/MIC42677.2020.9507772","DOIUrl":"https://doi.org/10.1109/NSS/MIC42677.2020.9507772","url":null,"abstract":"Non-local mean (NLM) denoising is commonly used for noise suppression in natural as well as medical imaging. Basically, the NLM filter takes advantage of the redundant information present in the image in the form of repeated structures/patterns to identify the underlying signals. In medical imaging (particularly PET and SPECT imaging), different representations of the image data under study (target or original image) could be reconstructed via applying different reconstruction settings. These representative (auxiliary) images bear very similar patterns/structures to the original/target image with different signal-to-noise ratios (SNR) which are ideal for use in the NLM denoising approach. This study proposed the multiple-reconstruction NLM filtering approach (referred to as MR-NLM) for noise reduction in PET imaging, wherein the redundant information present in auxiliary PET images are employed to conduct the NLM denoising process. The MR-NLM method relies on 12 additional PET image reconstructions (apart from the target PET image) using the same iterative algorithm with different iterations and subset numbers. Thereafter, for each target voxel, patches of voxels are extracted at the same location from all auxiliary PET images to be fed into the NLM smoothing process. To evaluate the performance of the MR-NLM algorithm, post-reconstruction denoising approaches including the conventional NLM, bilateral, and Gaussian filters were implemented and compared using 25 18F-FDG clinical whole-body (WB) PET/CT studies. The clinical studies demonstrated superior performance of the MR-NLM approach which established a promising compromise between noise suppression and preservation of the underlying signal/structures in PET images leading to higher SNR compared to the conventional NLM approach (34.9±5.7 versus 32.4±5.5). Though MR-NLM exhibited promising performance, this method suffers from long processing time due to the requirement of multiple reconstructions of raw PET data.","PeriodicalId":6760,"journal":{"name":"2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"19 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2020-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80167233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of Analog and Digital Signal Processing Chains for a Prototype TOF-PET System with 100 ps Coincidence Time Resolution 具有100ps符合时间分辨率的TOF-PET原型系统模拟和数字信号处理链的研究

2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) Pub Date : 2020-10-31 DOI: 10.1109/NSS/MIC42677.2020.9508016

S. Pourashraf, A. Gonzalez-Montoro, M. S. Lee, J. Cates, Jun Yeon Won, Zhixiang Zhao, Jae Sung Lee, C. Levin

引用次数: 3