37b Ultra-Fast, Radiation Hard Scintillators for High Energy Physics

Scintillators with very fast decay (< 20 ns) are needed to handle the very high event rate in future high energy physics (HEP) experiments. They are also expected to be extremely radiation hard without the necessity of replacement, to withstand integrated high absorbed doses of the order of hundred Mrads. The progress in the detection technology can be maintained and leveraged only if new materials are developed. In this project we plan to develop a novel ultra-fast, radiation-hard scintillator for new generation of calorimeters. To meet these requirements, we propose to investigate a set of promising new materials that rely on traditionally fast scintillation mechanisms such Donor-Acceptor Pair (DAP) luminescence, Core-to-Valence Luminescence (CVL), and Charge Transfer (CT) luminescence, and ultimately develop one of them for HEP Instrumentation. These materials include compositions based on: (1) TlCl; (2) Cs3ZnCl5 & Cs2ZnCl4; and (3) Lu2O3, respectively. In Phase I of this project, we will evaluate novel materials, including some level of compositional and dopant optimization. Several samples of TlCl, Cs2ZnCl4, Cs3ZnCl5 will be grown using the vertical Bridgman method and Lu2O3 samples will be manufactured using ceramic processing. The key element of evaluation will be the suitability of these materials for HEP experiments. Light yield, decay time and radiation hardness will be studied. In addition to high energy physics applications, ultra-fast and radiation hard materials would be attractive for high count rate applications such as nuclear fuel monitoring, dosimetry, detectors for measuring radiation in the event of a nuclear blast. The proposed materials can deliver performance that surpasses the benchmark materials at potentially lower cost.