Preface
Contrary to common perception, radiation has enormous potential of benefiting
mankind. For example, use of radiation in medical diagnostics in the form of CT and
nuclear scans has enabled the physicians to perform diagnoses that would not have
been possible otherwise. Another example is the use of radiation to destroy cancerous
growths, a process generally known asradiation therapy. Itistruethatradiation
can induce harm as well but a close examination reveals that its benefits certainly
outweigh its potential hazards. This realization has led to rapid advancements in
theory and applications of radiation interactions and its measurements. New types
of radiation detectors and sources are being constantly developed in laboratories
around the world. Also, a number of annually held international conferences are
devoted just to the developments of radiation measuring devices.
During my career as a physicist, working primarily on radiation detectors, I
always felt a need for a book that would not only discuss the technological aspects of
the field but would also give a thorough account of the underlying physical principles.
The scarcity of such books led me to think about writing one myself. However, those
who understand the field would appreciate that writing such a book is not an easy
task due mainly to the fast paced developments in the related technologies. The
strategy that I therefore adopted was to concentrate on theories, methodologies, and
technologies that are of fundamental value in terms of understanding the conceptual
basis of the radiation devices.
The sole purpose of the book is not to introduce the reader to the working prin-
ciples of different types of radiation detectors. It has been designed and written
such that it encompasses all aspects of design, development, and effective use of the
detection devices. Therefore chapters on statistics, data analysis, software for data
analysis, dosimetry, and spectroscopy have also been included. It can be used as
a text for related courses in physics, nuclear engineering, physical chemistry, and
medical physics. It can also be used as a reference by professionals and students
working in the related fields.
Most of the courses related to radiation measurements start with an introduction
to different types of radiation and their sources. I have adopted the same strat-
egy. The first chapter introduces the reader to various types of radiation and their
sources. It also includes sections on radioactivity and its measurements. Chapter
2 deals with the mechanisms by which radiation interacts with matter. Those who
want to understand the working principles of radiation detectors, must go through
this chapter as thoroughly as possible. The next chapter introduces the reader to the
principles of gas filled detectors, such as proportional counters. Gas filled detectors
are the earliest built radiation detectors and are still extensively used in different
fields. The important concepts, such as electron-ion pair generation, recombina-
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