We describe the concept of a new gamma ray scintronic detector targeting a time resolution of the order of 25 ps FWHM, with millimetric volume reconstruction and high detection efficiency. Its design consists of a monolithic large PbWO4 scintillating crystal with an efficient photocathode directly deposited on it. With an index of refraction higher for the photocathode than for the crystal, this design negates the total reflection effect of optical photons at the crystal/photo-detector optical interface, and thus largely improves optical coupling between the crystal and the photodetector. This allows to detect efficiently the Cherenkov light produced by 511 keV photoelectric conversions in PbWO4, and to optimize the detector time resolution. Furthermore, the low-yield, fast scintillation light produced additionally by PbWO4 increases the detected photon statistics by a factor 10, thus fostering accurate (3 dimensional) localization of the gamma ray interaction within the crystal and providing a fair measurement of the deposited energy. This paper lists the technological challenges that have to be overcome in order to build this scintronic detector. We show that all the key technologies have now been demonstrated and present results of a preliminary Monte Carlo simulation, which include an innovative event reconstruction algorithm to support the claimed performances of the detector.

中文翻译：

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针对伽马射线成像数十皮秒时间分辨率的“scintronic”晶体的设计研究：ClearMind 探测器

我们描述了一种新的伽马射线闪烁电子探测器的概念，其目标是 25 ps FWHM 数量级的时间分辨率，具有毫米体积重建和高探测效率。它的设计由一个整体式大 PbWO4 闪烁晶体和直接沉积在其上的高效光电阴极组成。由于光电阴极的折射率高于晶体，这种设计消除了晶体/光电探测器光学界面处光学光子的全反射效应，从而大大改善了晶体和光电探测器之间的光耦合。这允许有效地检测 PbWO4 中 511 keV 光电转换产生的切伦科夫光，并优化检测器的时间分辨率。此外，产量低，PbWO4 额外产生的快速闪烁光将检测到的光子统计数据增加了 10 倍，从而促进了晶体内伽马射线相互作用的准确（3 维）定位，并提供了对沉积能量的公平测量。本文列出了构建这种闪烁电子探测器必须克服的技术挑战。我们展示了所有关键技术现在都已得到证明，并展示了初步蒙特卡罗模拟的结果，其中包括创新的事件重建算法，以支持所声称的检测器性能。本文列出了构建这种闪烁电子探测器必须克服的技术挑战。我们展示了所有关键技术现在都已得到证明，并展示了初步蒙特卡罗模拟的结果，其中包括创新的事件重建算法，以支持所声称的检测器性能。本文列出了构建这种闪烁电子探测器必须克服的技术挑战。我们展示了所有关键技术现在都已得到证明，并展示了初步蒙特卡罗模拟的结果，其中包括创新的事件重建算法，以支持所声称的检测器性能。