Potential of Cerenkov Radiation for Fast Timing of TlBr Semiconductor Detectors for PET

切伦科夫辐射在 PET 中 TlBr 半导体探测器快速计时方面的潜力

• 批准号: 9437477
• 负责人: Gerard Ariño Estrada
• 金额: $ 7.85万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9437477
• 关键词: 3-Dimensional; Address; Behavior; Bismuth; Charge; Cherenkov Radiation; Communities; Coupled; Crystallization; Detection; Diagnostic Imaging; Diagnostics Research; Dimensions; Discipline of Nuclear Medicine; Environment; Face; Feasibility Studies; Gamma Rays; Generations; Geometry; Goals; Imaging Techniques; Light; Measurement; Measures; Medical Imaging; Methods; Modality; Modeling; Optics; Organ; Performance; Photons; Positron-Emission Tomography; Process; Production; Property; Publishing; Radiation; Refractive Indices; Reporting; Resolution; Semiconductors; Signal Transduction; Silicon; Spectrophotometry; Thick; Time; Tissues; Validation; Visible Radiation; Work; cherenkov imaging; detector; improved; in vivo; indexing; models and simulation; nanosecond; nuclear imaging; operation; photomultiplier; radiation detector; radiotracer; response; simulation; tool; transmission process

ABSTRACT A key limitation for using direct semiconductor detection for positron emission tomography (PET) is the relatively slow drift times of the charge carriers which leads to poor coincidence timing. We propose that Cerenkov light can be used as a fast timing signal in semiconductors such as TlBr. Cerenkov light is emitted quasi-instantaneously when a gamma-ray generates a photoelectron and has the potential to provide a signal with a time-of-flight precision even for semiconductor detectors. Cerenkov imaging has been proposed just a few years ago as a new modality and the first experimental results of Cerenkov light detection with BGO have been published recently, showing a coincidence time resolution of 270 ps. Cerenkov light in TlBr will be more intense than in BGO due to its higher index of refraction. The utilization of Cerenkov light as a fast timing signal in semiconductor detectors has not been reported yet. TlBr is an optimum detector for PET in terms of efficiency and energy resolution, however, its timing response compromises its overall performance. Using the Cerenkov light as a fast signal could provide TlBr with a time-of-flight timing performance and convert it into one of the most complete detectors for PET. The goal of this proposal is to demonstrate and characterize the detection of Cerenkov light in TlBr. The specific aims address understanding of the generation and transmission of Cerenkov light in TlBr, and the detection of this light using TlBr slabs coupled to photodetectors. The three specific aims of this project are 1) the measurement of visible light transmittance in TlBr, 2) the simulation of Cerenkov light generation in TlBr, and 3) the detection of Cerenkov light generated in TlBr and measurement of timing resolution. The experimental measurements will be used to validate the simulation and to obtain a toolkit able to predict reliably the Cerenkov light emitted by a TlBr slab depending on its dimensions and to extrapolate it to other semiconductor materials. These specific aims will be sufficient to prove the feasibility of using Cerenkov light as a fast signal in TlBr and to provide the semiconductor detector community with a simulation toolkit that facilitates the production of TlBr detectors optimized to detect Cerenkov light.

抽象的 使用直接半导体检测进行正电子发射断层扫描 (PET) 的一个关键限制是 电荷载流子的漂移时间相对较慢，这导致重合定时较差。我们建议 切伦科夫光可用作 TlBr 等半导体中的快速定时信号。发出切伦科夫光 当伽马射线产生光电子并有可能提供信号时准瞬时 即使对于半导体探测器也具有飞行时间精度。切伦科夫成像被提出只是 几年前，作为一种新的模式，切伦科夫光探测与 BGO 的第一个实验结果已经 最近发表，显示重合时间分辨率为 270 ps。 TlBr 中的切伦科夫光会更多 由于其折射率较高，因此比 BGO 更强烈。利用切伦科夫光作为快速定时信号 在半导体探测器中的应用尚未见报道。 TlBr 是 PET 的最佳检测器 然而，其时序响应会影响其整体性能。使用 切伦科夫光作为快速信号可以为 TlBr 提供飞行时间计时性能，并将其转换为 最完整的 PET 探测器之一。 该提案的目标是演示并表征 TlBr 中切伦科夫光的检测。这 具体目标是了解切伦科夫光在 TlBr 中的产生和传输，以及 使用与光电探测器耦合的 TlBr 板来检测这种光。该项目的三个具体目标是 1) TlBr 中可见光透过率的测量，2) TlBr 中切伦科夫光产生的模拟， 3) TlBr 中产生的切伦科夫光的检测和定时分辨率的测量。这 实验测量将用于验证模拟并获得能够预测的工具包 根据 TlBr 板的尺寸可靠地发射切伦科夫光，并将其外推到其他 半导体材料。 这些具体目标将足以证明使用切伦科夫光作为 TlBr 和 TlBr 中的快速信号的可行性 为半导体探测器社区提供有助于 TlBr 生产的模拟工具包 经优化以检测切伦科夫光的探测器。