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Event Shape Observables
In high energy physics, event shapes observables are quantities used to characterize the geometry of the outcome of a collision between high energy particles in a collider. Specifically, event shapes observables quantify the general pattern traced by the trajectories of the particles resulting from the collision.V. D. Barger, R. J. N. Phillips (1997) “Collider Physics” Frontier in Physics, Addison-Wesley Publishing Company, Inc.M. Dasgupta and G. P. Salam (2004)Event shapes in e+ e- annihilation and deep inelastic scattering J. Phys. G 30, R143preprint The most common event shape observables include: *The sphericity; *The aplanarity; *The thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that syst .... *The C-parameter; *The jet broadening. References Experimental particle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Particle Physics
Particle physics or high energy physics is the study of fundamental particles and forces that constitute matter and radiation. The fundamental particles in the universe are classified in the Standard Model as fermions (matter particles) and bosons (force-carrying particles). There are three generations of fermions, but ordinary matter is made only from the first fermion generation. The first generation consists of up and down quarks which form protons and neutrons, and electrons and electron neutrinos. The three fundamental interactions known to be mediated by bosons are electromagnetism, the weak interaction, and the strong interaction. Quarks cannot exist on their own but form hadrons. Hadrons that contain an odd number of quarks are called baryons and those that contain an even number are called mesons. Two baryons, the proton and the neutron, make up most of the mass of ordinary matter. Mesons are unstable and the longest-lived last for only a few hundredths of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collider
A collider is a type of particle accelerator which brings two opposing particle beams together such that the particles collide. Colliders may either be ring accelerators or linear accelerators. Colliders are used as a research tool in particle physics by accelerating particles to very high kinetic energy and letting them impact other particles. Analysis of the byproducts of these collisions gives scientists good evidence of the structure of the subatomic world and the laws of nature governing it. These may become apparent only at high energies and for tiny periods of time, and therefore may be hard or impossible to study in other ways. Explanation In particle physics one gains knowledge about elementary particles by accelerating particles to very high kinetic energy and letting them impact on other particles. For sufficiently high energy, a reaction occurs that transforms the particles into other particles. Detecting these products gives insight into the physics involved. To do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust (particle Physics)
In high energy physics, thrust is a property, (one of the event shape observables) used to characterize the collision of high energy particles in a collider. When two high energy particles collide, they typically produce jets of secondary particles. This happens when one or several quark-antiquark pairs are produced during the collision. Each colored quark/antiquark pair travels its separate way and subsequently hadronizes. Many new particles are created by the hadronization process and travel in approximately the same direction as the original pair. This set of particles constitutes a jet. The thrust S. Brandt, C. Peyrou, R. Sosnowski, and A. Wroblewski (1964), “The Principal axis of jets. An Attempt to analyze high-energy collisions as two-body processes“, Phys. Lett. 12 57–61. E. Farhi (1977), “A QCD Test for Jets“, Phys. Rev. Lett. 39 1587–1588. quantifies the coherence, or ″jettiness″ of the group of particles resulting from one collision. It is defined as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
