Improvement of several properties of lead tungstate crystals with different doping ions

A very good radiation resistance of Lead Tungstate crystals is mandatory for their use in the high precision electromagnetic calorimeter of the CMS experiment at LHC. Since the beginning of 1996 we have organised systematic investigations of the parameters influencing the radiation hardness of this crystal. Two classes of parameters have been particularly studied, the first one related to the control of the stoichiometry and structure associated defects, the second one connected with the suppression and the charge compensation of existing defects with different kinds of doping ions. This paper reports about the second part of this study and complements a first paper where the role of the stoichiometry was already discussed. Results of tests are given on a significant statistical sample of full size crystals ( 23cm) which show a considerable improvement in the optical properties and the radiation resistance of appropriately doped crystals

Conference on Engineering of Scintillation Materials and Radiation Technologies

This volume provides a broad overview of the latest achievements in scintillator development, from theory to applications, and aiming for a deeper understanding of fundamental processes, as well as the discovery and availability of components for the production of new generations of scintillation materials. It includes papers on the microtheory of scintillation and the initial phase of luminescence development, applications of the various materials, and development and characterization of ionizing radiation detection equipment. The book also touches upon the increased demand for cryogenic scintillators, the renaissance of  garnet materials for scintillator applications, nano-structuring in scintillator development, development and applications for security, and exploration of hydrocarbons and ecological monitoring

Inorganic scintillators for detector systems: physical principles and crystal engineering

This second edition features new chapters highlighting advances in our understanding of the behavior and properties of scintillators, and the discovery of new families of materials with light yield and excellent energy resolution very close to the theoretical limit. The book focuses on the discovery of next-generation scintillation materials and on a deeper understanding of fundamental processes. Such novel materials with high light yield as well as significant advances in crystal engineering offer exciting new perspectives. Most promising is the application of scintillators for precise time tagging of events, at the level of 100 ps or higher, heralding a new era in medical applications and particle physics. Since the discovery of the Higgs Boson with a clear signature in the lead tungstate scintillating blocks of the CMS Electromagnetic Calorimeter detector, the current trend in particle physics is toward very high luminosity colliders, in which timing performance will ultimately be essential to mitigating pile-up problems. New and extremely fast light production mechanisms based on Hot-Intraband-Luminescence as well as quantum confinement are exploited for this purpose. Breakthroughs such as crystal engineering by means of co-doping procedures and selection of cations with small nuclear fragmentation cross-sections will also pave the way for the development of more advanced and radiation-hard materials. Similar innovations are expected in medical imaging, nuclear physics ecology, homeland security, space instrumentation and industrial applications. This second edition also reviews modern trends in our understanding and the engineering of scintillation materials. Readers will find new and updated references and information, as well as new concepts and inspirations to implement in their own research and engineering endeavors

Physics of fast processes in scintillators

This book presents the current advances in understanding of the fast excitation transfer processes in inorganic scintillation materials, the discovery of new materials exhibiting excellent time resolution, and the results on the evaluation of timing limits for scintillation detectors. The book considers in-depth basic principles of primary processes in energy relaxation, which play a key role in creating scintillating centers to meet a growing demand for knowledge to develop new materials combining high energy and time resolutions. The rate of relaxation varies. However, the goal is to make it extremely fast, occurring within the ps domain or even shorter. The book focuses on fast processes in scintillation materials. This approach enables in-depth understanding of fundamental processes in scintillation and supports the efforts to push the time resolution of scintillation detectors towards 10 ps target. Sophisticated theoretical and advanced experimental research conducted in the last decade is reviewed. Engineering and control of the energy transfer processes in the scintillation materials are addressed. The new era in development of instrumentation for detection of ionizing radiation in high- energy physics experiments, medical imaging and industrial applications is introduced. This book reviews modern trends in the description of the scintillation build up processes in inorganic materials, transient phenomena, and engineering of the scintillation properties. It also provides reliable background of scientific and educational information to stimulate new ideas for readers to implement in their research and engineering. The book is aimed at providing a coherent updated background of scientific and instructive information to stimulate new ideas for readers in their research and engineering

Inorganic Scintillators for Detector Systems: Physical Principles and Crystal Engineering

The development of new scintillators as components of modern detector systems is increasingly defined by the end user's needs. This book provides an introduction to this emerging topic at the interface of physics and materials sciences, with emphasis on bulk inorganic scintillators. After surveying the end user's needs in a vast range of applications, ranging from astrophysics to industrial R & D, the authors move on to review scintillating mechanisms and the properties of the most important materials used. A chapter on crystal engineering and examples of recent developments in the field of high-energy physics and medical imaging introduce the reader to the practical aspects. This book will benefit researchers and scientists working in academic and industrial R & D related to the development of scintillators

PbWO4 Crystals Radiation Hardness Test Setup at the CERN General Irradiation Facility

The CMS PWO crystals irradiation facility installed at the CERN GIF ( General Irradiation Facility) is described. The measurement method and corresponding stability issues are discussed. The setup was successfully used in the PWO crystals technology optimisation R&D, results of which are illustrated

On the Origin of the Transmission Damage in Lead Tungstate Crystals Under Irradiation

The origin of the transmission damage in PWO crystals is discussed. It is shown that both electron and hole centers created on the basis of structural defects in PbWO4 crystals contributed to the induced absorption of the crystals. The different aspects of the suppression of the recharge processes in PWO scintillation crystals are also discussed

Nanoscale Engineering of Inorganic Composite Scintillation Materials

This review article considers the latest developments in the field of inorganic scintillation materials. Modern trends in the improvement of inorganic scintillation materials are based on engineering their features at the nanoscale level. The essential challenges to the fundamental steps of the technology of inorganic glass, glass ceramics, and ceramic scintillation materials are discussed. The advantage of co-precipitation over the solid-state synthesis of the raw material compositions, particularly those which include high vapor components is described. Methods to improve the scintillation parameters of the glass to the level of single crystals are considered. The move to crystalline systems with the compositional disorder to improve their scintillation properties is justified both theoretically and practically. A benefit of the implementation of the discussed matters into the technology of well-known glass and crystalline scintillation materials is demonstrated