Heavy Quark Physics Aneesh V. Manohar and Mark B. Wise Cambridge U. Press, New York, 2000. $64.95 (191 pp.). ISBN 0-521-64241-8
Intense experimental and theoretical studies of heavy quark systems have allowed for precise measurements of fundamental parameters of the Standard Model of electroweak interactions. The inherent difficulty in extracting these parameters is that the strongly interacting particles created in the laboratory, such as the B meson or the Λc baryon, are nonperturbative composites of the quark and gluon fields whose dynamics are defined by the Standard Model. The theoretical framework with which heavy quark systems are understood and described has evolved from the phenomenological models of the strong interaction of the early 1980s to that of the rigorous heavy quark effective field theory used today.
The monograph Heavy Quark Physics , by Aneesh V. Manohar and Mark B. Wise, is the first text devoted to the theoretical treatment of heavy quark systems. This is a detailed and well-thought-out presentation by two world-renowned experts on the theoretical techniques used to understand high-precision data on systems containing heavy quarks. The symmetries uncovered by Nathan Isgur and Wise (both recipients, along with Mikhail Voloshin, of the 2001 J. J. Sakurai Prize from the American Physical Society) that become manifest in the heavy quark limit form the backbone of this text and enable Manohar and Wise to move seamlessly among different aspects of heavy quark physics. With the introductory chapter providing a concise review of the Standard Model, loops, and effective field theory techniques, it can be considered self-contained. However, a firm background in field theory and particle phenomenology allows for a much more rewarding experience with this text. It is oriented toward those who wish to learn to calculate various quantities of importance in heavy quark systems and provides all the details necessary to do so. At the end of each chapter, problems are given that either develop a point discussed in the chapter or enable the reader to tackle issues beyond those discussed. References to important published papers relevant to the content of each chapter are also included.
After a thorough discussion of relations between observables that are a direct result of the spin and flavor symmetries existing in the heavy quark limit, such as those between matrix elements for decay, the text moves on to discuss the implementation of corrections to the heavy quark limit. These corrections allow a connection with the charm and bottom quark sectors. Considerations of the perturbative quantum-chromodynamic (QCD) corrections in αs (MQ ), including matching for heavy–heavy and heavy–light currents, and of nonperturbative corrections in Λ QCD /MQ , including discussions of Luke’s theorem, culminate in the determination of the weak mixing angle Vbc from exclusive B meson decays.
The synthesis of heavy quark and chiral symmetry necessary to describe the low-momentum processes of baryons and mesons containing heavy quarks, such as strong decay widths and the radiative decays of the D* mesons is detailed. A nice comparison is made here among the implications of the D* widths for constants in the heavy quark chiral Lagrangian, results from lattice QCD, and predictions of the nonrelativistic quark model. However, the reader is left wanting more on this subject, as the discussion could have been somewhat more detailed and could have included heavy baryons.
The area of inclusive weak semileptonic decays, which developed somewhat after the initial work on the impact of heavy quark symmetries on exclusive decays and on meson spectroscopy, is discussed in great detail. After addressing important issues concerning the endpoint of the electron spectrum in B → Xcev and B → Xuev, a determination of Vbc made possible by these tools is presented.
In recent years, much effort has been spent on understanding systems with more than one heavy quark. However, this text is clearly focused on detailing the accomplishments in systems with only one heavy quark, and discussion of nonrelativistic QCD is confined to only a brief outline.
To summarize, this is a wonderful text for graduate students in particle and nuclear physics who are interested in learning the tools of heavy quark physics from two of the experts in the field. This book is a must for both particle theorists and experimentalists who are currently researching heavy quark systems. In many ways, this text should be considered a sequel to Howard Georgi’s Weak Interactions and Modern Particle Physics (Addison-Wesley, 1984).
