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Heavy ion reactions, Lectures Notes: vol. 1-Elastic and inelastic reactions
614
Nuclear Instruments and Methods 198 (1982) 614 North-Holland Publishing Company
BOOK REVIEW
R I C A R D O A. B R O G L I A and A A G E W I N T E R , Heavy ion reactions, Lecture Notes: vol. 1-Elastic and inelastic reactions (Benjamin, R e a d i n g - L o n d o n - A m s t e r d a m - D o n Mills-Sydney-Tokyo) (1981) pp. 291, $29,50. The series Frontiers in physics is intended to bridge the gap between current research publications and formal monographs. The latest contribution to this series, Heavy ion reactions I by Ricardo A. Broglia and Aage Winter is based on a series of lectures these authors have given in Copenhagen and Stony Brook. In this volume Coulomb excitation with heavy ions and the elastic and inelastic scattering of heavy ions are considered. The treatment where the incoming ion and the target nucleus have a more violent encounter will appear in volume II which will be published shortly. The first chapter of volume I, serves as an introduction to both volumes. Here, a qualitative account of all the p h e n o m e n a one encounters in heavy ion reactions is presented. In particular the authors discuss the new phenomenon of "deep inelastic scattering" and the possibilities of studying the nuclear structure at high spins by means of heavy ion reactions. The second chapter is devoted to Coulomb excitation. This process is always important because with heavy ions the Coulomb field is often so strong that both projectile and target are multiply excited before they actually make contact. The Coulomb excitation mechanism is treated in the approximation where the projectile follows a classical trajectory that is unaffected by the excitation. The general equations of the time dependant Hamiltonian are then solved for the special cases of an ideal vibrator and an ideal rotor. The excitation probability of surface modes in deformed nuclei as well as the coherently produced deformation and rotation in spherical and deformed nuclei, respectively are also calculated. At energies above the Coulomb barrier the elastic scattering of the incoming ions is affected by the nuclear i o n - i o n potential. This process is the subject of the third chapter in which the i o n - i o n potential is first estimated both by means of folding techniques and by the use of proximity forces. The scattering in this potential is then treated with both classical, semiclassical and q u a n t u m mechanical methods. In the fourth and last chapter the nuclear inelastic scatter-
0167-5087/82/0000-0000/$02.75
© 1982 N o r t h - H o l l a n d
ing and the interference between the nuclear and the Coulomb inelastic scattering are considered. The inelastic excitation probability depends primarily on the form factor i.e. on the overlap between the nuclear wave functions and the interaction. These form factors are obtained for both single particle excitations and for several types of collective excitations. Using the developed formalism the authors then discussed energy weighted sum rules and the origin of the imaginary part of the optical potential. Heavy ion reactions I, contains 69 figures and about 750 numbered formulae and since the average reader will have to make frequent use of pen and paper to verify these formulae, it takes a substantial effort to fully comprehend the text. A definite asset of the present book is that it gives a complete classical description of heavy ion scattering a subject that is poorly documented in the literature. Furthermore, most phen o m e n a are discussed from several point of views. This has the negative consequence that the book at first glance appears confusing, but the m a n y alternative descriptions do, however, give more insight into the reaction mechanisms. According to the authors a complete awareness of all the possible methods and approximations will also be necessary for an understanding of the more complicated situations that will be dealt with in volume II. Nevertheless, the m a n y different ways 9 f approaching the same problems should be of great value for the experimentalist who wishes to discuss and understand his own experiments and who looks for ideas for new experiments. The book should also be well suited for those graduate students in theoretical physics who wish to specialize in nuclear reaction theory. As a final word of critisism I should like to mention that the authors like most other authors in the field of theoretical physics, tacitly assume the old cgs units. For someone who like myself is used to rationalized units it is not always obvious how to translate the formulae into the numbers that should be compared to experiment. A better definition of and a more frequent mention of appropriate units would have made the book more useful for the nuclear reaction practitioner. Sven H J O R T H
Nuclear Instruments and Methods 198 (1982) 614 North-Holland Publishing Company
BOOK REVIEW
R I C A R D O A. B R O G L I A and A A G E W I N T E R , Heavy ion reactions, Lecture Notes: vol. 1-Elastic and inelastic reactions (Benjamin, R e a d i n g - L o n d o n - A m s t e r d a m - D o n Mills-Sydney-Tokyo) (1981) pp. 291, $29,50. The series Frontiers in physics is intended to bridge the gap between current research publications and formal monographs. The latest contribution to this series, Heavy ion reactions I by Ricardo A. Broglia and Aage Winter is based on a series of lectures these authors have given in Copenhagen and Stony Brook. In this volume Coulomb excitation with heavy ions and the elastic and inelastic scattering of heavy ions are considered. The treatment where the incoming ion and the target nucleus have a more violent encounter will appear in volume II which will be published shortly. The first chapter of volume I, serves as an introduction to both volumes. Here, a qualitative account of all the p h e n o m e n a one encounters in heavy ion reactions is presented. In particular the authors discuss the new phenomenon of "deep inelastic scattering" and the possibilities of studying the nuclear structure at high spins by means of heavy ion reactions. The second chapter is devoted to Coulomb excitation. This process is always important because with heavy ions the Coulomb field is often so strong that both projectile and target are multiply excited before they actually make contact. The Coulomb excitation mechanism is treated in the approximation where the projectile follows a classical trajectory that is unaffected by the excitation. The general equations of the time dependant Hamiltonian are then solved for the special cases of an ideal vibrator and an ideal rotor. The excitation probability of surface modes in deformed nuclei as well as the coherently produced deformation and rotation in spherical and deformed nuclei, respectively are also calculated. At energies above the Coulomb barrier the elastic scattering of the incoming ions is affected by the nuclear i o n - i o n potential. This process is the subject of the third chapter in which the i o n - i o n potential is first estimated both by means of folding techniques and by the use of proximity forces. The scattering in this potential is then treated with both classical, semiclassical and q u a n t u m mechanical methods. In the fourth and last chapter the nuclear inelastic scatter-
0167-5087/82/0000-0000/$02.75
© 1982 N o r t h - H o l l a n d
ing and the interference between the nuclear and the Coulomb inelastic scattering are considered. The inelastic excitation probability depends primarily on the form factor i.e. on the overlap between the nuclear wave functions and the interaction. These form factors are obtained for both single particle excitations and for several types of collective excitations. Using the developed formalism the authors then discussed energy weighted sum rules and the origin of the imaginary part of the optical potential. Heavy ion reactions I, contains 69 figures and about 750 numbered formulae and since the average reader will have to make frequent use of pen and paper to verify these formulae, it takes a substantial effort to fully comprehend the text. A definite asset of the present book is that it gives a complete classical description of heavy ion scattering a subject that is poorly documented in the literature. Furthermore, most phen o m e n a are discussed from several point of views. This has the negative consequence that the book at first glance appears confusing, but the m a n y alternative descriptions do, however, give more insight into the reaction mechanisms. According to the authors a complete awareness of all the possible methods and approximations will also be necessary for an understanding of the more complicated situations that will be dealt with in volume II. Nevertheless, the m a n y different ways 9 f approaching the same problems should be of great value for the experimentalist who wishes to discuss and understand his own experiments and who looks for ideas for new experiments. The book should also be well suited for those graduate students in theoretical physics who wish to specialize in nuclear reaction theory. As a final word of critisism I should like to mention that the authors like most other authors in the field of theoretical physics, tacitly assume the old cgs units. For someone who like myself is used to rationalized units it is not always obvious how to translate the formulae into the numbers that should be compared to experiment. A better definition of and a more frequent mention of appropriate units would have made the book more useful for the nuclear reaction practitioner. Sven H J O R T H