Scintillation detectors exhibiting high spatial resolution and fast timing capabilities are of vital importance for synchrotron sources. These detectors may be exposed to a variety of X-ray energies (up to 140 keV) and used in high frame rate applications. Here, we describe the advances in the development of thin-film LuI₃:Ce scintillators for higher energy X-ray imaging, with fast timing and high spatial resolution. When grown in a single crystalline form, these scintillators are bright, producing 115 000 photons/MeV. However, to achieve high spatial resolution, these scintillators are grown in thin-film form with a microcolumnar structure, controllable to column diameters of < 1– $30~\mu \text{m}$ . Thus, a much thicker scintillator layer ( $10~\mu \text{m}$ –3 mm or higher) may be grown, providing superior X-ray absorption while achieving high resolutions of $50~\mu \text{m}$ or better, at the cost of reduced light yield. To study the timing characteristics of the scintillator, time-resolved X-ray excited optical luminescence (TR-XEOL) was performed on two different sets of three samples of LuI₃ at the 1-BM beamline of the Advanced Photon Source at Argonne National Laboratory. Besides, we report timing measurements obtained using a photomultiplier tube (PMT) and oscilloscope at Radiation Monitoring Devices (RMD) Inc. Using the TR-XEOL, we determined the decay constants of LuI₃ as a function of Ce doping, recording a fast decay component as low as 3.6 ns (39%), one of the fastest values recorded in inorganic scintillators. This fast decay opens up numerous novel applications, where ultrahigh frame rates are important using synchrotron X-rays. This article will discuss fabrication, characterization, and potential applications for this novel scintillator.

中文翻译：

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用于快速计时应用的高分辨率超快 LuI3:Ce 闪烁体的进展

具有高空间分辨率和快速计时能力的闪烁探测器对于同步加速器源至关重要。这些探测器可能会暴露于各种 X 射线能量（高达 140 keV）并用于高帧率应用。在这里，我们描述了用于更高能量 X 射线成像、具有快速计时和高空间分辨率的薄膜 LuI ₃ :Ce 闪烁体的开发进展。当以单晶形式生长时，这些闪烁体是明亮的，产生 115 000 光子/MeV。然而，为了实现高空间分辨率，这些闪烁体以薄膜形式生长，具有微柱结构，柱直径可控<1- $30~\mu \text{m}$ . 因此，一个更厚的闪烁体层（ $10~\mu \text{m}$ –3 mm 或更高）可以生长，提供卓越的 X 射线吸收，同时实现高分辨率 $50~\mu \text{m}$ 或者更好，以降低光输出为代价。为了研究闪烁体的时序特性，在阿贡国家实验室高级光子源的 1-BM 光束线上对两组不同的三个 LuI ₃样品进行了时间分辨 X 射线激发光学发光 (TR-XEOL) . 此外，我们报告了使用辐射监测设备 (RMD) 公司的光电倍增管 (PMT) 和示波器获得的定时测量结果。使用 TR-XEOL，我们确定了 LuI ₃的衰减常数作为 Ce 掺杂的函数，记录的快速衰减分量低至 3.6 ns (39%)，这是无机闪烁体中记录的最快值之一。这种快速衰减开辟了许多新颖的应用，其中使用同步加速器 X 射线的超高帧速率很重要。本文将讨论这种新型闪烁体的制造、表征和潜在应用。