1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255)最新文献_第6页

Development of a hard X-ray polarimeter for astrophysics 天体物理用硬x射线偏振计的研制

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.775233

M. McConnell, J. Macri, M. McClish, J. Ryan, D. Forrest, W. Vestrand

引用次数: 13

Fast-channel LSO detectors and fiber-optic encoding for excellent dual photon transmission measurements in PET 用于PET中优异双光子传输测量的快速通道LSO探测器和光纤编码

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.774355

W. Jones, J. C. Moyers, M. Casey, C. Watson, R. Nutt

{"title":"Fast-channel LSO detectors and fiber-optic encoding for excellent dual photon transmission measurements in PET","authors":"W. Jones, J. C. Moyers, M. Casey, C. Watson, R. Nutt","doi":"10.1109/NSSMIC.1998.774355","DOIUrl":"https://doi.org/10.1109/NSSMIC.1998.774355","url":null,"abstract":"Improved attenuation correction remains critical to PET. Currently with dual photon rotating rod sources, benefits of windowing are limited by counting losses of detectors nearest the rods, the near detectors. With single photon sources, improved statistics are offset by a greater need for collimation and more complex emission background correction. Now, a dual photon point source array with fast-channel, near detectors improves on these earlier techniques-here, adding transmission measurement to dual-head rotating PET. Arrays of collimated point sources (/sup 68/Ge/Ga-3 to 21 per head) are aligned axially and orbit the FOV. With each source is a dedicated near detector (LSO crystal). Crystals couple to photomultipliers (PMTs). As the crystals are not \"block\" encoded, pulse processing time is reduced (to 120 ns). Reduced processing time lowers dead time and permits hotter sources. For improved axial sampling, larger arrays (21 sources/head) may be configured. To reduce cost, crystals couple fiber-optically into unique PMT pairs-decreasing the total number of near-detector PMTs by 71%.","PeriodicalId":129202,"journal":{"name":"1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125042961","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: 11

Moderator-free neutron detection 无慢化剂中子探测

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.775161

R. Hansen, A. J. Peurrung, P. Reeder, D.C. Stromswold

引用次数: 0

Investigation of depth-of-interaction by pulse shape discrimination in multicrystal detectors read out by avalanche photodiodes 雪崩光电二极管读出的多晶探测器中脉冲形状判别的相互作用深度研究

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.774351

A. Saoudi, C. Pepin, F. Dion, M. Bentourkia, R. Lecomte, M. Andreaco, Michael E. Casey, R. Nutt, H. Dautet

{"title":"Investigation of depth-of-interaction by pulse shape discrimination in multicrystal detectors read out by avalanche photodiodes","authors":"A. Saoudi, C. Pepin, F. Dion, M. Bentourkia, R. Lecomte, M. Andreaco, Michael E. Casey, R. Nutt, H. Dautet","doi":"10.1109/NSSMIC.1998.774351","DOIUrl":"https://doi.org/10.1109/NSSMIC.1998.774351","url":null,"abstract":"The measurement of depth of interaction (DOI) within detectors is necessary to improve resolution uniformity across the FOV of small diameter PET scanners. DOI encoding by pulse shape discrimination (PSD) has definite advantages as it requires only one readout per pixel and it allows DOI measurement of photoelectric and Compton events. The PSD time characteristics of various scintillators were studied with avalanche photodiodes (APD) and the identification capability was tested in multi-crystal assemblies with up to four scintillators. In the PSD time spectrum of an APD-GSO/LSO/BGO/CsI(Tl) assembly, four distinct peaks at 45, 26, 88 and 150 ns relative to a fast test pulse, having resolution of 10.6, 5.2, 20 and 27 ns, can be easily separated. Whereas the number and position of scintillators affect detector performance, the ability to identify crystals is not compromised. Compton events have a significant effect on PSD accuracy, suggesting that photopeak energy gating should be used for better crystal identification. More sophisticated PSD techniques using parametric time-energy histograms also improve crystal identification in cases where PSD time or energy discrimination alone is inadequate. These results confirm the feasibility of PSD DOI encoding with APDs for PET.","PeriodicalId":129202,"journal":{"name":"1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129889797","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: 135

A novel low noise mixed signal switched CMOS readout chain for imaging-spectroscopic pixel X-ray detectors 一种用于成像光谱像素x射线探测器的新型低噪声混合信号开关CMOS读出链

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.775174

C. Kapnistis, K. Misiakos, N. Haralabidis

引用次数: 0

PET attenuation correction using mean attenuation coefficients: a simulation study 利用平均衰减系数校正PET衰减:模拟研究

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.773895

M. Madsen

引用次数: 3

Position and energy resolution of a new gamma-ray detector based on a single CsI(Tl) scintillator coupled to a silicon drift chamber array 基于单CsI(Tl)闪烁体与硅漂移室阵列耦合的新型伽玛射线探测器的位置和能量分辨率

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.774293

C. Fiorini, A. Longoni, L. Boschini, F. Perotti, C. Labanti, E. Rossi, P. Lechner, L. Struder

{"title":"Position and energy resolution of a new gamma-ray detector based on a single CsI(Tl) scintillator coupled to a silicon drift chamber array","authors":"C. Fiorini, A. Longoni, L. Boschini, F. Perotti, C. Labanti, E. Rossi, P. Lechner, L. Struder","doi":"10.1109/NSSMIC.1998.774293","DOIUrl":"https://doi.org/10.1109/NSSMIC.1998.774293","url":null,"abstract":"We have developed a first prototype of gamma-ray detector for imaging and spectroscopy which is based on a single CsI(Tl) scintillator coupled to a linear array of silicon drift chambers (SDCs). The detector performs the measurement of the position of interaction in one coordinate, by the centroid method, and the measurement of the /spl gamma/ photon energy, by summing the signals of all the single units. The small size and the compactness of the CsI(Tl)-SDC assembly make this detector scheme an interesting solution for the realization of small scintillation cameras for nuclear medicine. Moreover, the low electronics noise offered by the SDC allows to reach good performances in both position and energy resolution. The first experimental results obtained on the prototype are reported in this work. A position resolution better than 1 mm FWHM and an energy resolution of about 16% FWHM at 122 keV have been measured. A comparison of the experimental results with the results of Monte Carlo simulations is also reported.","PeriodicalId":129202,"journal":{"name":"1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255)","volume":"188 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129150580","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: 21

The ASDQ ASIC [Central Outer Tracker CDF upgrade application] ASDQ ASIC[中央外部跟踪器CDF升级应用]

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.775180

W. Bokhari, J. Heinrich, N. Lockyer, F. Newcomer

引用次数: 2

Validation of new Gibbs priors for Bayesian tomographic reconstruction using physically acquired data 使用物理获取的数据进行贝叶斯层析重建的新Gibbs先验验证

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.773846

S. J. Lee, Y. Choi, Gene Gindi

{"title":"Validation of new Gibbs priors for Bayesian tomographic reconstruction using physically acquired data","authors":"S. J. Lee, Y. Choi, Gene Gindi","doi":"10.1109/NSSMIC.1998.773846","DOIUrl":"https://doi.org/10.1109/NSSMIC.1998.773846","url":null,"abstract":"The variety of Bayesian MAP approaches to tomography proposed in recent years can both stabilize reconstructions and lead to improved bias and variance. In the authors' previous work (see S.J. Lee et al., IEEE Trans. Med. Imaging, vol. MI-14, no. 4, p. 669-80, 1995; S.J. Lee et al., IEEE Trans. Nucl. Sci., vol. NS-44, no. 3, p. 1381-7, 1997), they showed that the thin-plate (TP) prior, which is less sensitive to variations in first spatial derivatives than the conventional membrane (MM) prior, yields improved reconstructions in the sense of low bias. In spite of the several advantages of such quadratic smoothing priors, they are still less than ideal due to their limitations in edge preservation. Here, the authors use a convex-nonquadratic potential function, which provides a degree of edge preservation. As in the case of quadratic priors, a class of two-dimensional smoothing splines with first and second partial derivatives are applied to the new potential function. In order to reduce difficulties such as oversmoothing for MM and edge overshooting for TP, the authors also generalize the prior energy definition to that of a linear combination of MM and TP using a control parameter, and observe its transition between the two extreme cases. To observe the efficacies of their new priors, the authors use physically acquired PET emission data. They also test these priors in a transmission setting with physically acquired transmission data. The authors' results indicate significant improvements in the quality of both emission and transmission images using their new priors.","PeriodicalId":129202,"journal":{"name":"1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130589188","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

Monte Carlo investigation of the charge sharing effects in 3-D position sensitive CdZnTe gamma ray spectrometers 三维位置敏感CdZnTe伽马能谱仪中电荷共享效应的蒙特卡罗研究

1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) Pub Date : 1998-11-08 DOI: 10.1109/NSSMIC.1998.775219

Y. F. Du, Z. He, W. Li, G. Knoll, D. Wehe

引用次数: 20