The work presented in this thesis spans a wide range of experimental particle physics subjects, starting from level-1 trigger electronics to the final results of the search for Higgs boson decay and to tau lepton pairs. The thesis describes an innovative reconstruction algorithm for tau decays and details how it was instrumental in providing a measurement of Z decay to tau lepton pairs. The reliability of the analysis is fully established by this measurement before the Higgs boson decay to tau lepton pairs is considered. The work described here continues to serve as a model for analysing CMS Higgs to tau leptons measurements.
The work presented in this thesis spans a wide range of experimental particle physics subjects, starting from level-1 trigger electronics to the final results of the search for Higgs boson decay and to tau lepton pairs. The thesis describes an innovative reconstruction algorithm for tau decays and details how it was instrumental in providing a measurement of Z decay to tau lepton pairs. The reliability of the analysis is fully established by this measurement before the Higgs boson decay to tau lepton pairs is considered. The work described here continues to serve as a model for analysing CMS Higgs to tau leptons measurements.
The Higgs boson is an undiscovered elementary particle, thought to be a vital piece of the closely fitting jigsaw of particle physics. Like all particles, it has wave properties akin to those ripples on the surface of a pond which has been disturbed; indeed, only when the ripples travel as a well defined group is it sensible to speak of a particle at all. In quantum language the analogue of the water surface which carries the waves is called a field. Each type of particle has its own corresponding field. The Higgs field is a particularly simple one -- it has the same properties viewed from every direction, and in important respects in indistinguishable from empty space. Thus physicists conceive of the Higgs field being "switched on", pervading all of space and endowing it with "grain" like that of a plank of wood. The direction of the grain in undetectable, and only becomes important once the Higgs' interactions with other particles are taken into account. for instance, particles call vector bosons can travel with the grain, in which case they move easily for large distances and may be observed as photons - that is, particles of light that we can see or record using a camera; or against, in which case their effective range is much shorter, and we call them W or Z particles. These play a central role in the physics of nuclear reactions, such as those occurring in the core of the sun. The Higgs field enables us to view these apparently unrelated phenomenon as two sides of the same coin; both may be described in terms of the properties of the same vector bosons. When particles of matter such as electrons or quarks (elementary constituents of protons and neutrons, which in turn constitute the atomic nucleus) travel through the grain, they are constantly flipped "head-over-heels". this forces them to move more slowly than their natural speed, that of light, by making them heavy.
The study of neutrinos and their interaction with matter has made many important contributions to our present knowledge of physics. This advanced text introduces neutrino physics and presents a theoretical framework for describing relativistic particles. It gives a pedagogical description of the neutrino, its properties, the standard model of electroweak interactions, and neutrino scattering from leptons and nucleons. Focusing on the role of nuclear effects, the discussion extends to various processes of quasielastic, inelastic, and deep inelastic scattering from nucleons and nuclei. Neutrino sources, detection and oscillation, along with the role of neutrinos in astrophysics and motivation for the need of physics beyond the standard model are discussed in detail. This topical book will stimulate new ideas and avenues for research, and will form a valuable resource for advanced students and researchers working in the field of neutrino physics.
Ken Ford’s mission is to help us understand the “great ideas” of quantum physics—ideas such as wave-particle duality, the uncertainty principle, superposition, and conservation. These fundamental concepts provide the structure for 101 Quantum Questions, an authoritative yet engaging book for the general reader in which every question and answer brings out one or more basic features of the mysterious world of the quantum—the physics of the very small. Nuclear researcher and master teacher, Ford covers everything from quarks, quantum jumps, and what causes stars to shine, to practical applications ranging from lasers and superconductors to light-emitting diodes. Ford’s lively answers are enriched by Paul Hewitt's drawings, numerous photos of physicists, and anecdotes, many from Ford’s own experience. Organized for cover-to-cover reading, 101 Quantum Questions also is great for browsing. Some books focus on a single subject such as the standard model of particles, or string theory, or fusion energy. This book touches all those topics and more, showing us that disparate natural phenomena, as well as a host of manmade inventions, can be understood in terms of a few key ideas. Yet Ford does not give us simplistic explanations. He assumes a serious reader wanting to gain real understanding of the essentials of quantum physics. Ken Ford's other books include The Quantum World: Quantum Physics for Everyone (Harvard 2004), which Esquire magazine recommended as the best way to gain an understanding of quantum physics. Ford's new book, a sequel to the earlier one, makes the quantum world even more accessible.
Who made modern Britain? This book, drawn from the award-winning Oxford Dictionary of National Biography, tells the story of our recent past through the lives of those who shaped national life. Following on from the Oxford DNB's first supplement volume-noteworthy people who died between 2001 and 2004-this new volume offers biographies of more than 850 men and women who left their mark on twentieth and twenty-first century Britain, and who died in the years 2005 to 2008. Here are the people responsible for major developments in national life: from politics, the arts, business, technology, and law to military service, sport, education, science, and medicine. Many are closely connected to specific periods in Britain's recent history. From the 1950s, the young Harold Pinter or the Yorkshire cricketer, Fred Trueman, for example. From the Sixties, the footballer George Best, photographer Patrick Lichfield, and the Pink Floyd musician, Syd Barrett. It's hard to look back to the 1970s without thinking of Edward Heath and James Callaghan, who led the country for seven years in that turbulent decade; or similarly Freddie Laker, pioneer of budget air travel, and the comedians Ronnie Barker and Dave Allen who entertained with their sketch shows and sit coms. A decade later you probably browsed in Anita Roddick's Body Shop, or danced to the music of Factory Records, established by the Manchester entrepreneur, Tony Wilson. In the 1990s you may have hoped that 'Things can only get better' with a New Labour government which included Robin Cook and Mo Mowlam. Many in this volume are remembered for lives dedicated to a profession or cause: Bill Deedes or Conor Cruise O'Brien in journalism; Ned Sherrin in broadcasting or, indeed, Ted Heath whose political career spanned more than 50 years. Others were responsible for discoveries or innovations of lasting legacy and benefit-among them the epidemiologist Richard Doll, who made the link between smoking and lung cancer, Cicely Saunders, creator of the hospice movement, and Chad Varah, founder of the Samaritans. With John Profumo-who gave his name to a scandal-policeman Malcolm Fewtrell-who investigated the Great Train Robbery-or the Russian dissident Aleksandr Litvinenko-who was killed in London in 2006-we have individuals best known for specific moments in our recent past. Others are synonymous with popular objects and experiences evocative of recent decades: Mastermind with Magnus Magnusson, the PG-Tips chimpanzees trained by Molly Badham, John DeLorean's 'gull-wing' car, or the new British Library designed by Colin St John Wilson-though, as rounded and balanced accounts, Oxford DNB biographies also set these events in the wider context of a person's life story. Authoritative and accessible, the biographies in this volume are written by specialist authors, many of them leading figures in their field. Here you will find Michael Billington on Harold Pinter, Michael Crick on George Best, Richard Davenport-Hines on Anita Roddick, Brenda Hale on Rose Heilbron, Roy Hattersley on James Callaghan, Simon Heffer on John Profumo, Douglas Hurd on Edward Heath, Alex Jennings on Paul Scofield, Hermione Lee on Pat Kavanagh, Geoffrey Wheatcroft on Conor Cruise O'Brien, and Peregrine Worsthorne on Bill Deedes. Many in this volume are, naturally, household names. But a good number are also remembered for lives away from the headlines. What in the 1980s became 'Thatcherism' owed much to behind the scenes advice from Ralph Harris and Alfred Sherman; children who learned to read with Ladybird Books must thank their creator, Douglas Keen; while, without its first producer, Verity Lambert, there would have been no Doctor Who. Others are 'ordinary' people capable of remarkable acts. Take, for instance, Arthur Bywater who over two days in 1944 cleared thousands of bombs from a Liverpool munitions factory following an explosion-only to do the same, months later, in an another factory. Awarded the George Cross and the George Medal, Bywater remains the only non-combatant to have received Britain's two highest awards for civilian bravery.
