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Theory of complex nuclei
Book reviews which the microscopic theory of superfluidity is discussed. By no stretch of the imagination can this be of value to reactor physicists, but it is certainly a fascinating field of study. Chapter XII deals with the theory of quantum transitions under the influence of an external perturbation. In this connection we find a calculation of the excitation of an atom by a heavy charged particle passing by. This is directly related to the stopping cross section for calculating ranges. Chapter X I I I provides some interesting topics relating to statistical quantum theory. The density matrix is defined and the Liouville equation solved for some simple problems, one of which concerns the transfer of energy from a donor to an acceptor in the presence of a dissipative medium. The fluctuation-dissipation theorem is introduced and discussed. Scattering theory is the subject of Chapter XIV. This is a topic which is directly relevant to reactor theory since at the heart of m o d e r n transport calculations lies the scattering kernel. The Born approximation is set out, as also are its correction terms. The cross section for screened coulomb, Gaussian and rectangular spherical well potentials are calculated. Partial wave theory is discussed and the concept of scattering leng.th described. The general theory of inelastic scattering processes is introduced and applied to the scattering of an electron by an atom. R e a r r a n g e m e n t collisions are dealt with and this leads on to the scattering matrix. Using this theory, D a v y d o v describes the scattering of slow neutrons by nuclei and derives the B r e i t - W i g n e r resonance formula and related interference terms. R e g g e poles are introduced and the ideas of complex angular m o m e n t u m explained. Finally, we are given an elementary but lucid discussion of the coherent and incoherent scattering of slow neutrons in crystalline materials which will serve as a useful introduction for students to the more general Van H o v e formalism. The book terminates with a chapter on the chemical bond. There are the usual mathematical appendices, all of which are of direct relevance to reactor physics. In summary, then, this is a good book which is up-to-date, relevant to reactor physicists and inexpensive. M. M. R. WILLIAMS
Pro[essor o[ Nuclear Engineering, Queen Mary College, University of London Theory of Complex Nuclei, V. G. Soloviev, Trans. P. Vogel Pergamon Press, 1976, Price $35 or £17'50 The "complex nuclei" of the title are those of atomic mass of the order of 60 or higher. Since even the lightest
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nuclei are too complex for a complete solution, approximation methods must be used. This book is a discussion in some depth of certain theoretical methods which have been developed for the calculation of the collective properties of heavier nuclei. It is not a text of nuclear theory of the usual kind, and penetrates deeply into nuclear theory on a fairly narrow -'ront. As we know, phenomenological collective models, according to which the nucleus vibrates or rotates as a whole, give a very good account of many energies and transition rates of the lower lying states of almost all heavier nuclei. However, the calculation of the "inertia" and "stiffness" parameters for spherical and deformed nuclei and the moments of inertia and "shapes" of deformed nuclei are difficult problems to which Soloviev and his school have made important contributions. After a brief summary of collective model phenomenology, the book contains an exposition of methods applied by Soloviev and others to these problems. The emphasis is upon the use of simplified forces (pairing plus quadrupole) which make detailed solutions computationally straightforward, although it is not clear what can still be achieved with these very schematic interactions. This leads to an important warning that must be made. Most of the work described in this book was completed by about 1966, and the work of the 1966-1970 period is not treated in depth. A translator's addendum of five pages points to more recent work but the references still only cover 1969-1973. This is unfortunate in a book published in 1976. As a case in point, although Hartree-Fock is basic for the formal development, the treatment of actual HF calculations reads as if nothing had been published since 1966. The place of the Random Phase Approximation in nuclear physics has shifted from the low frequency vibrations treated in the book to the giant dipole vibrations which are not discussed. I feel that this book is not consistent in the level of the reader being aimed at, and would not be useful as a sole text for nuclear theory. However, experimentalists and theorists studying heavy deformed nuclei will find much of value, not least its excellent bibliography of the microscopic collective model. Nuclear physics libraries should have copies of this book since it makes accessible the best presentation of the work of a major contributor to the field. Moreover, it is good that students be exposed to a style of physics which is a little different from that of most textbooks they will see. The translation is adequate, and the production is good except for an index which is too short. There is no name index. I like the way in which the publishers have put a large amount of material into as compact a form as possible, keeping down the cost without loss of readability. However, this translation should have been published five years earlier.
NuclearPhysics Laboratory, Ox[ord,England
R. S. MACKINTOSH
Pro[essor o[ Nuclear Engineering, Queen Mary College, University of London Theory of Complex Nuclei, V. G. Soloviev, Trans. P. Vogel Pergamon Press, 1976, Price $35 or £17'50 The "complex nuclei" of the title are those of atomic mass of the order of 60 or higher. Since even the lightest
43
nuclei are too complex for a complete solution, approximation methods must be used. This book is a discussion in some depth of certain theoretical methods which have been developed for the calculation of the collective properties of heavier nuclei. It is not a text of nuclear theory of the usual kind, and penetrates deeply into nuclear theory on a fairly narrow -'ront. As we know, phenomenological collective models, according to which the nucleus vibrates or rotates as a whole, give a very good account of many energies and transition rates of the lower lying states of almost all heavier nuclei. However, the calculation of the "inertia" and "stiffness" parameters for spherical and deformed nuclei and the moments of inertia and "shapes" of deformed nuclei are difficult problems to which Soloviev and his school have made important contributions. After a brief summary of collective model phenomenology, the book contains an exposition of methods applied by Soloviev and others to these problems. The emphasis is upon the use of simplified forces (pairing plus quadrupole) which make detailed solutions computationally straightforward, although it is not clear what can still be achieved with these very schematic interactions. This leads to an important warning that must be made. Most of the work described in this book was completed by about 1966, and the work of the 1966-1970 period is not treated in depth. A translator's addendum of five pages points to more recent work but the references still only cover 1969-1973. This is unfortunate in a book published in 1976. As a case in point, although Hartree-Fock is basic for the formal development, the treatment of actual HF calculations reads as if nothing had been published since 1966. The place of the Random Phase Approximation in nuclear physics has shifted from the low frequency vibrations treated in the book to the giant dipole vibrations which are not discussed. I feel that this book is not consistent in the level of the reader being aimed at, and would not be useful as a sole text for nuclear theory. However, experimentalists and theorists studying heavy deformed nuclei will find much of value, not least its excellent bibliography of the microscopic collective model. Nuclear physics libraries should have copies of this book since it makes accessible the best presentation of the work of a major contributor to the field. Moreover, it is good that students be exposed to a style of physics which is a little different from that of most textbooks they will see. The translation is adequate, and the production is good except for an index which is too short. There is no name index. I like the way in which the publishers have put a large amount of material into as compact a form as possible, keeping down the cost without loss of readability. However, this translation should have been published five years earlier.
NuclearPhysics Laboratory, Ox[ord,England
R. S. MACKINTOSH