CP Violation (2nd edition) by I I Bigi and A I Sanda, Cambridge University Press. Hardback ISBN 9780521847940, £80 ($160). E-book ISBN 9780511577284, $128.
At the time of the first edition of this book, 10 years ago, the authors had, in their words, “ample reasons to expect imminent dramatic changes" in the land of discrete symmetries. With this second edition, they return to cover what has indeed happened since then. There was certainly drama in the sense of “action" on the experimental side and many of the players became better defined. Experiments at CERN and Fermilab have measured direct ΔS=1 CP violation in KL decays, with consistent results and a precision of a few per cent, and the B factories have revealed the large CP asymmetries expected in the B sector. Also, precision measurements with the SNO, K2K and KamLAND experiments have opened the way to CP violation studies with neutrinos.
In this second edition, the authors include the new results and update the theoretical models. They indicate new directions in model building, in particular in the context of supersymmetry and extra dimensions, and are always attentive to questions that remain unanswered. Are there additional sources of CP violation? What happens in the lepton sector? What is the origin of the baryon asymmetry?
The structure of the book remains unchanged, consisting of three parts, slightly rearranged with respect to the first edition. Each chapter includes an introduction, a short summary and a number of problems (but no hints for solutions).
Part 1, on “Basics of CP violation", follows a pedagogical style, leading from symmetry concepts in classical mechanics and electrodynamics to their translation to the domain of non-relativistic quantum mechanics, and subsequently to relativistic quantum theories. It is completed by two sections on the historical role of strange particles, in particular neutral kaons, in the discovery of CP violation and on the simple “master equations" of time evolution.
In Part 2, “Theory and experiments", the authors deal with decays, i.e. the directly observable phenomena. This starts with details of the phenomenology related to kaons and the latest experimental results. It leads, via a history of the Standard Model, to the Kobayashi-Maskawa ansatz and the need for at least three families. It is here, in chapter 10, that the forecasts of the first edition are shown to materialize, with the experimental opportunities offered by B physics. The late 1990s saw the construction of the asymmetric B factories and finally in 2001 the demonstration of CP violation, with a multi-standard-deviation effect, for the first time outside the kaon domain, in four decay channels.
A glimpse beyond the Standard Model forms the content of Part 3, starting with a quest for CP violation in the neutrino sector and possible corrections to the current paradigms. It then leads on to top quarks and charged leptons, supersymmetry, minimal flavour-violation and extra dimensions, and baryogenesis in the universe.
Part 4 consists of only one chapter. Here, in their dashing style at its best, the authors recall that CP violation represents “a profound intellectual insight" that also has “many and far-reaching concrete consequences". Although the three-family Standard Model can implement CP violation through the KM mechanism, we have not yet reached an understanding of it, for we are left with the mysteries related to the quark mass matrices. After looking back to the successes of the past, the authors advance an “Agenda for the future". Happily (from the point of view of an experimentalist) this agenda covers many different experimental fields, so there will be no shortage of work.
The cut of the book is theoretical but is suitable and stimulating for an experimentalist, showing rigour and insight. The authors concede that it does not make easy reading and more than one reading may be necessary. Sometimes other sources (quoted as references) may also be needed. Some lack of precision in the historical details could have been avoided, and the bibliography would gain from a less casual presentation. The tone is friendly, however, even if the jocular comments are occasionally puzzling. The reader is shown how to see the CP “wood" among the “trees" of phenomenological details, without missing anything of importance.
Maria Fidecaro, CERN.
Books received
Principles of Radiation Interaction in Matter and Detection (2nd edition) by Claude Leroy and Pier-Giorgio Rancoita, World Scientific. Hardback ISBN 9789812818270, £112 ($191). Paperback ISBN 9789812818287, £61 ($104).
This book addresses the fundamental principles of interactions between radiation and matter and the principle of particle detectors in a range of fields, from low to high energy, including space physics and the medical environment. It provides abundant information about the processes of electromagnetic and hadronic energy deposition in matter, detecting systems, and the performance and optimization of detectors. In this second edition, new sections dedicated to the following topics are included: space and the high-energy physics radiation environment, non-ionizing energy loss, displacement damage in silicon devices and detectors, single-event effects, detection of slow and fast neutrons with silicon detectors, solar cells and pixel detectors. This book will be of use to students as a reference for courses in particle, astroparticle and space physics and instrumentation, as well as researchers dealing with instrumentation in particle physics. Part of it is directed toward courses in medical physics.
Of Matter and Spirit: Selected Essays by Charles P Enz, World Scientific. Hardback ISBN 9789812819000, £48 ($83).
The essays selected for this book comprise ideas presented in oral or written form between the years 1972 and 2000, some of which were originally given in French or German. They are preceded by a biographical and topical introduction. As the title suggests, one major theme of the essays collected here is the material world, which is viewed in its extreme spatial extensions of the universe and of the elementary particles. In particular, the fascinating notion of the void and its fluctuating energy is the subject of various discussions, as is the subdivision of material bodies and its limits. The latter, as well as the limit of gravitational stability, are depicted in a diagram leading to the ultimate point of the Planck mass and length. The other topic of the title is the spiritual realm and here the book’s content is based on reflections and quotations from various religious texts.