Brian R. Martin - Particle Physics

This edition first published 2017
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ISBN: 9781118911907 (hardback), 9781118912164 (paperback)

But why are such terrific efforts made just to find new particles? asked Mr Tompkins.

Well, this is science, replied the professor, the attempt of the human mind to understand everything around us, be it giant stellar galaxies, microscopic bacteria, or these elementary particles. It is interesting and exciting, and that is why we are doing it.

From Mr Tompkins Tastes a Japanese Meal, by George Gamow (Mr Tompkins in Paperback, Cambridge University Press (1965), p.186).

A brief overview is given in Chapters 1, 2 and 3. For a short course, follow these chapters plus Chapters 4 and 5, Sections 6.1, 6.2, 6.4, 7.1, 7.2, 8.1, 8.2, Chapters 9 and 10, plus Sections 11.1 and 11.2.1, omitting all starred material throughout.

The starred items contain more specialised or advanced material that is not required elsewhere in the book. They may be omitted at a first reading and used for reference when you want to know about a particular topic.

The pictures on the front cover show two Higgs boson production events obtained at the LHC accelerator at CERN. The larger circle shows the decay of the Higgs to four electrons (indicated by the blue and red lines) obtained by the ATLAS collaboration and the smaller circle shows the decay of the Higgs to two gamma rays (indicated by the green lines) obtained by the CMS collaboration.

The Manchester Physics Series is a set of textbooks at first degree level. It grew out of the experience at the University of Manchester, widely shared elsewhere, that many textbooks contain much more material than can be accommodated in a typical undergraduate course; and that this material is only rarely so arranged as to allow the definition of a short self-contained course. The plan for this series was to produce short books so that lecturers would find them attractive for undergraduate courses, and so that students would not be frightened off by their encyclopaedic size or price. To achieve this, we have been very selective in the choice of topics, with the emphasis on the basic physics together with some instructive, stimulating and useful applications.

Although these books were conceived as a series, each of them is self-contained and can be used independently of the others. Several of them are suitable for wider use in other sciences. Each Author's Preface gives details about the level, prerequisites, etc., of that volume.

The Manchester Physics Series has been very successful since its inception over 40 years ago, with total sales of more than a quarter of a million copies. We are extremely grateful to the many students and colleagues, at Manchester and elsewhere, for helpful criticisms and stimulating comments. Our particular thanks go to the authors for all the work they have done, for the many new ideas they have contributed, and for discussing patiently, and often accepting, the suggestions of the editors.

Finally we would like to thank our publishers, John Wiley & Sons, Ltd., for their enthusiastic and continued commitment to the Manchester Physics Series.

J. R. Forshaw
H. F. Gleeson
F. K. Loebinger
August 2014

Particle Physics is the study of the fundamental constituents of matter and the forces between them. For almost 40 years these have been described by the so-called standard model of particle physics, which provides, at least in principle, a basis for understanding most particle interactions, except gravity. The purpose of this book is to provide a short introduction to particle physics, which emphasises the foundations of the standard model in experimental data, rather than its more formal and theoretical aspects. The book is intended as an introduction to the subject for undergraduate students who have previously taken introductory courses in non-relativistic quantum mechanics and special relativity. No prior knowledge of particle physics is assumed.

The introductory nature of the book and the need to keep it reasonably short have influenced both the level of the treatment and the choice of material. We have tried to take a direct approach throughout, focusing on the interpretation of experimental data in terms of the basic properties of quarks and leptons, and extensive use has been made of symmetry principles and Feynman diagrams, which are introduced early in the book. We have not given any detailed calculations using the Feynman rules, since these are beyond the scope of a typical introductory undergraduate course.