and simple differential equations is also assumed. In reflection of my own interests
(and understanding), the treatment here is restricted to World War II-era fission
bombs. As I am neither a professional nuclear physicist nor a weapons designer,
readers seeking information on postwar advances in bomb and reactor design and
issues such as isotope separation techniques will have to look elsewhere; a good
source is Garwin and Charpak (2001). Similarly, this book does not treat the effects
of nuclear weapons, for which authoritative analyses are available (Glasstone and
Dolan 1977). For readers seeking more extensive references, an annotated bibliography appears in Appendix J.
This book comprises 34 sections within five main chapters; Chap. 6 comprises
several appendices. Chapter 1 examines some of the history of the discovery of the
remarkable amounts of energy released in nuclear reactions, the discovery of the
neutron, and characteristics of the fission process. Chapter 2 details how one can
estimate the critical mass of fissile material necessary for both untamped and
tamped fission weapons, and the explosive yield one might expect of a weapon.
Aspects of producing fissile material by separating uranium isotopes and synthesizing plutonium are taken up in Chap. 3. Chapter 4 examines some complicating
factors that weapons engineers need to be aware of. Some miscellaneous calculations comprise Chap. 5. Useful data are summarized in Appendices A and B, and a
number of background derivations are gathered in Appendices C–G. For readers
wishing to try their own hand at calculations, Appendix H offers a number of
exercises, with answers provided. A number of symbols are used in this text to
designate different quantities in different places, and a Glossary of the most
important ones appears in Appendix I. A bibliography for further reading is offered
in Appendix J, and some useful constants and conversion factors appear in
Appendix K. The order of the main chapters, and particularly of individual sections
within them, proceeds in such a way that understanding of later ones often depends
on knowledge of earlier ones: Physics is a vertically-integrated discipline.
I have developed spreadsheets for carrying out a number of the calculations
described in this book, and which are intended to be used in working some of the
exercises in Appendix H. I used to maintain a website from which these were
obtainable, but that was becoming expensive. Even institutional links can be
volatile, so I ask readers who are interested in obtaining the spreadsheets to contact
me directly at reed@alma.edu: I intend to be around for a while. When spreadsheets
are discussed in the text, they are referred to in bold type.
It should be emphasized that there is no material in the present work that cannot
be gleaned from publicly-available texts, journals, and websites: I have no access to
classified material.
For many years now, I have benefitted from spoken and electronic conversations, correspondence, suggestions, willingness to read and comment on draft
material, and general encouragement from John Abelson, Joseph-James Ahern,
John Altholz, Dana Aspinall, Albert Bartlett, Jeremy Bernstein, Alan Carr, David
Cassidy, John Coster-Mullen, Steve Croft, Peter Dawson, Gene Deci, Eric
Erpelding, Patricia Ezzell, Charles Ferguson, Henry Frisch, Ed Gerjuoy, Chris
Gould, Dick Groves, Robert Hayward, Dave Hafemeister, Art Hobson, William
x
Preface to the Fourth Edition
(and understanding), the treatment here is restricted to World War II-era fission
bombs. As I am neither a professional nuclear physicist nor a weapons designer,
readers seeking information on postwar advances in bomb and reactor design and
issues such as isotope separation techniques will have to look elsewhere; a good
source is Garwin and Charpak (2001). Similarly, this book does not treat the effects
of nuclear weapons, for which authoritative analyses are available (Glasstone and
Dolan 1977). For readers seeking more extensive references, an annotated bibliography appears in Appendix J.
This book comprises 34 sections within five main chapters; Chap. 6 comprises
several appendices. Chapter 1 examines some of the history of the discovery of the
remarkable amounts of energy released in nuclear reactions, the discovery of the
neutron, and characteristics of the fission process. Chapter 2 details how one can
estimate the critical mass of fissile material necessary for both untamped and
tamped fission weapons, and the explosive yield one might expect of a weapon.
Aspects of producing fissile material by separating uranium isotopes and synthesizing plutonium are taken up in Chap. 3. Chapter 4 examines some complicating
factors that weapons engineers need to be aware of. Some miscellaneous calculations comprise Chap. 5. Useful data are summarized in Appendices A and B, and a
number of background derivations are gathered in Appendices C–G. For readers
wishing to try their own hand at calculations, Appendix H offers a number of
exercises, with answers provided. A number of symbols are used in this text to
designate different quantities in different places, and a Glossary of the most
important ones appears in Appendix I. A bibliography for further reading is offered
in Appendix J, and some useful constants and conversion factors appear in
Appendix K. The order of the main chapters, and particularly of individual sections
within them, proceeds in such a way that understanding of later ones often depends
on knowledge of earlier ones: Physics is a vertically-integrated discipline.
I have developed spreadsheets for carrying out a number of the calculations
described in this book, and which are intended to be used in working some of the
exercises in Appendix H. I used to maintain a website from which these were
obtainable, but that was becoming expensive. Even institutional links can be
volatile, so I ask readers who are interested in obtaining the spreadsheets to contact
me directly at reed@alma.edu: I intend to be around for a while. When spreadsheets
are discussed in the text, they are referred to in bold type.
It should be emphasized that there is no material in the present work that cannot
be gleaned from publicly-available texts, journals, and websites: I have no access to
classified material.
For many years now, I have benefitted from spoken and electronic conversations, correspondence, suggestions, willingness to read and comment on draft
material, and general encouragement from John Abelson, Joseph-James Ahern,
John Altholz, Dana Aspinall, Albert Bartlett, Jeremy Bernstein, Alan Carr, David
Cassidy, John Coster-Mullen, Steve Croft, Peter Dawson, Gene Deci, Eric
Erpelding, Patricia Ezzell, Charles Ferguson, Henry Frisch, Ed Gerjuoy, Chris
Gould, Dick Groves, Robert Hayward, Dave Hafemeister, Art Hobson, William
x
Preface to the Fourth Edition