List of particles - Wikipedia, the free encyclopedia. This is a list of the different types of particles found or believed to exist in the whole of the universe. In particle physics, an elementary particle or fundamental particle is a particle whose substructure is unknown, thus it is unknown whether it is composed of other particles. Known elementary particles include the fundamental. For individual lists of the different particles, see the list below. Elementary particles. They are the fundamental objects of quantum field theory. Many families and sub- families of elementary particles exist. Elementary particles are classified according to their spin. Fermions have half- integer spin while bosons have integer spin. All the particles of the Standard Model have been experimentally observed, recently including the Higgs boson. Fermion particles are described by Fermi. They include the quarks and leptons, as well as any composite particles consisting of an odd number of these, such as all baryons and many atoms and nuclei. Fermions have half- integer spin; for all known elementary fermions this is 1. All known fermions, except neutrinos, are also Dirac fermions; that is, each known fermion has its own distinct antiparticle. It is not known whether the neutrino is a Dirac fermion or a Majorana fermion. They are classified according to whether they interact via the color force or not. In the Standard Model, there are 1. Quarks are the fundamental constituents of hadrons and interact via the strong interaction. Quarks are the only known carriers of fractional charge, but because they combine in groups of three (baryons) or in groups of two with antiquarks (mesons), only integer charge is observed in nature. Their respective antiparticles are the antiquarks, which are identical except that they carry the opposite electric charge (for example the up quark carries charge +2. There are six flavors of quarks; the three positively charged quarks are called . Their respective antiparticles are the antileptons which are identical, except for the fact that they carry the opposite electric charge and lepton number. The antiparticle of an electron is an antielectron, which is nearly always called a . There are six leptons in total; the three charged leptons are called . Neutrinos are known to oscillate, so that neutrinos of definite flavor do not have definite mass, rather they exist in a superposition of mass eigenstates. The hypothetical heavy right- handed neutrino, called a . Bosons are characterized by Bose. Bosons may be either elementary, like photons and gluons, or composite, like mesons. According to the Standard Model the elementary bosons are: Elementary bosons responsible for the four fundamental forces of nature are called force particles (gauge bosons). Strong interaction is mediated by the gluon, weak interaction is mediated by the W and Z bosons, and it is sometimes hypothetized that gravitation is mediated by the graviton, although it is not predicted by the Standard Model but by other theories in the framework of quantum field theory. The Higgs boson is postulated by the electroweak theory primarily to explain the origin of particle masses. In a process known as the . The Minimal Supersymmetric Standard Model (MSSM) predicts several Higgs bosons. A new particle expected to be the Higgs boson was observed at the CERN/LHC on March 1. Ge. V with an accuracy of close to five sigma (9. The Higgs mechanism giving mass to other particles has not been observed yet. Hypothetical particles. The graviton is hypothetical, too . They are predicted by some GUTs. The extra- dimensional momentum is manifested as extra mass in four- dimensional spacetime. The Elementary Particles. 19-09-2016 2/2 The Elementary Particles. Other Files Available to Download Forces of Nature Four forces responsible for all phenomena INTRODUCTION TO ELEMENTARY PARTICLES David Griffiths Reed College WILEY- VCH WILEY-VCH Verlag GmbH & Co. The online version of Elementary Particles by Luke Yuan on ScienceDirect.com, the world's leading platform for high quality peer-reviewed full-text books. 1 The periodic table of elementary particles Ding-Yu Chung P.O. Box 180661, Utica, Michigan 48318, USA All leptons, quarks, and gauge bosons can be placed in the periodic table of elementary particles. The periodic table is. Composite particles. Hadrons are either: Composite fermions (especially 3 quarks), in which case they are called baryons. Composite bosons (especially 2 quarks), in which case they are called mesons. A Different Approach on Elementary Particles James Keele 3313 Camino Cielo Vista Santa Fe, NM 87507 email [email protected] The Bohr Atom Model explains the basic light spectra of the hydrogen atom. The approach taken here is.Quark models, first proposed in 1. Murray Gell- Mann and George Zweig (who called quarks . The gluon tubes or flux tubes are now known to be Y shaped. Ordinary baryons (composite fermions) contain three valence quarks or three valence antiquarks each. Nucleons are the fermionic constituents of normal atomic nuclei. Protons, composed of two up and one down quark (uud)Neutrons, composed of two down and one up quark (ddu)Hyperons, such as the . Although not normally present in atomic nuclei, they can appear in short- lived hypernuclei. A number of charmed and bottom baryons have also been observed. BEAM LINE 19 the mass of its constituents. The composite nature of such a particle would be far from obvious. How could one tell which of these particles is elementary and which composite? As soon as this question was asked. Some hints at the existence of exotic baryons have been found recently; however, negative results have also been reported. Their existence is uncertain. Pentaquarks consist of four valence quarks and one valence antiquark. Because mesons have spin of 0 or 1 and are not themselves elementary particles, they are . Examples of mesons include the pion, kaon, and the J/. In quantum hydrodynamic models, mesons mediate the residual strong force between nucleons. At one time or another, positive signatures have been reported for all of the following exotic mesons but their existences have yet to be confirmed. A tetraquark consists of two valence quarks and two valence antiquarks; A glueball is a bound state of gluons with no valence quarks; Hybrid mesons consist of one or more valence quark- antiquark pairs and one or more real gluons. Atomic nuclei. In the nucleus, the protons are in red and neutrons are in purple. In reality, the nucleus is also spherically symmetrical. Atomic nuclei consist of protons and neutrons. Each type of nucleus contains a specific number of protons and a specific number of neutrons, and is called a . Nuclear reactions can change one nuclide into another. See table of nuclides for a complete list of isotopes. Atoms are the smallest neutral particles into which matter can be divided by chemical reactions. An atom consists of a small, heavy nucleus surrounded by a relatively large, light cloud of electrons. Each type of atom corresponds to a specific chemical element. To date, 1. 18 element have been discovered. The atomic nucleus consists of protons and neutrons. Protons and neutrons are, in turn, made of quarks. Molecules. Each type of molecule corresponds to a specific chemical compound. Molecules are a composite of two or more atoms. See list of compounds for a list of molecules. A molecule is generally combined in a fixed proportion. It is the most basic unit of matter and is homogenous. Condensed matter. As a result, much of the theory of particle physics applies to condensed matter physics as well; in particular, there are a selection of field excitations, called quasi- particles, that can be created and explored. These include: An anyon is a generalization of fermion and boson in two- dimensional systems like sheets of graphene that obeys braid statistics. A plekton is a theoretical kind of particle discussed as a generalization of the braid statistics of the anyon to dimension > 2. A WIMP (weakly interacting massive particle) is any one of a number of particles that might explain dark matter (such as the neutralino or the axion). The pomeron, used to explain the elastic scattering of hadrons and the location of Regge poles in Regge theory. The skyrmion, a topological solution of the pion field, used to model the low- energy properties of the nucleon, such as the axial vector current coupling and the mass. A genon is a particle existing in a closed timelikeworld line where spacetime is curled as in a Frank Tipler or Ronald Malletttime machine. A goldstone boson is a massless excitation of a field that has been spontaneously broken. The pions are quasi- goldstone bosons (quasi- because they are not exactly massless) of the broken chiralisospin symmetry of quantum chromodynamics. A goldstino is a goldstone fermion produced by the spontaneous breaking of supersymmetry. An instanton is a field configuration which is a local minimum of the Euclidean action. Instantons are used in nonperturbative calculations of tunneling rates. A dyon is a hypothetical particle with both electric and magnetic charges. A geon is an electromagnetic or gravitational wave which is held together in a confined region by the gravitational attraction of its own field energy. An inflaton is the generic name for an unidentified scalar particle responsible for the cosmic inflation. A spurion is the name given to a.
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