Recent Advances in Ceramic Scintillators
- PDF / 1,464,284 Bytes
- 8 Pages / 612 x 792 pts (letter) Page_size
- 5 Downloads / 253 Views
1038-O06-02
Recent Advances in Ceramic Scintillators Edgar V Van Loef1, Yimin Wang1, Jarek Glodo1, Charles Brecher2, Alex Lempicki2, and Kanai S Shah1 1 RMD, 44 Hunt Street, Watertown, MA, 02472 2 ALEM Associates, 44 Hunt Street, Watertown, MA, 02472 ABSTRACT A review is presented of recent ceramic scintillator R&D. Attention is focussed on Ce doped gamma-ray scintillators for medical imaging applications. Ceramic scintillators discussed in detail include SrHfO3:Ce and Lu2Hf2O7:Ce. These materials combine a high density and high atomic number with fast emission and a good light yield and may find practical application in medical imaging modalities such as Positron Emission Tomography and Computed Tomography. INTRODUCTION Inorganic scintillators coupled to optical detectors such as photomultiplier tubes (PMTs) or silicon photodiodes provide detection and spectroscopy of ionizing radiation and charged particles by converting ionizing radiation into optical photons, which are subsequently detected by the PMT or photodiode. These devices are an important part of medical imaging applications such as positron emission tomography (PET) and computed tomography (CT), find practical use in nuclear and particle physics experiments, and are indispensable for nuclear non-proliferation. While most efforts have been directed towards the research and development of novel inorganic single crystals for scintillation detection, the field of ceramic scintillators has only received scant attention since the development of the HiLightTM scintillator by General Electric. This is in part due to the difficult task of fabricating transparent ceramics from non-cubic materials and the manufacturing of large volume devices. Recently however, ceramic scintillators are gaining interest because they may be produced in transparent forms from noncubic materials using nanotechnology and alternative chemical synthesis routes. In this paper we will present a historical overview of ceramic scintillators. Scintillation properties of various translucent/transparent ceramic scintillators are reported. We will limit the discussion of novel transparent ceramics to the manufacturing and characterization of SrHfO3:Ce and Lu2Hf2O7:Ce ceramics. Conventional and novel chemical methods to synthesize powders are described and techniques to manufacture ceramic scintillators such as hot pressing and hot isostatic pressing are detailed. Finally, the optical and scintillation properties by means of radioluminescence, pulse height, luminescence decay and timing measurements are presented. HISTORY The use of polycrystalline transparent ceramics for scintillation detection is a rather novel approach, no older than a few decades. A graphical overview of the history of ceramic scintillators is shown in figure 1. Whereas the first inorganic single crystal scintillators were explored during the early 40’s and 50’s in conjunction with the development of the photomultiplier tube [1], the first polycrystalline ceramic scintillators were developed at a much
later stage using t
Data Loading...
