The Standard Model

Hadron - a particle made of quarks. The name was proposed by the Russian theoretical physicist Lev Okun, who wrote: "… I shall call strongly interacting particles 'hadrons'… the Greek hadros signifies "large", "massive", in contrast to leptos which means "small", "light". I hope that this terminology will prove to be convenient." It is in CERN's Large Hadron Collider, a machine in which hadrons are accelerated to high speeds and smashed together, that footprints of the Higgs boson have been spotted. Lepton - a type of elementary particle (examples include electrons and neutrinos), from the Greek "leptos" meaning "small" or "thin." The best known of all leptons is the electron, which governs all of chemistry as it is found in atoms and is directly tied to all chemical properties. Electron - an indivisible quantity of electric charge, proposed in 1894 by the Irish physicist, George Johnston Stoney (1826-1911). Derived from the word "electric" (or the Latin "electrum") plus the Greek suffix "-on". The electron (symbol: e−) is a subatomic particle with a negative elementary electric charge. An electron has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton. The intrinsic angular momentum (spin) of the electron is a half-integer value in units of ħ, which means that it is a fermion. The antiparticle of the electron is called the positron; it is identical to the electron except that it carries electrical and other charges of the opposite sign. When an electron collides with a positron, both particles may be totally annihilated, producing gamma ray photons. Electrons, which belong to the first generation of the lepton particle family, participate in gravitational, electromagnetic and weak interactions. Like all matter, they have quantum mechanical properties of both particles and waves, so they can collide with other particles and can be diffracted like light. However, this duality is best demonstrated in experiments with electrons, due to their tiny mass. Since an electron is a fermion, no two electrons can occupy the same quantum state, in accordance with the Pauli exclusion principle. The concept of an indivisible quantity of electric charge was theorized to explain the chemical properties of atoms, beginning in 1838 by British natural philosopher Richard Laming. Photon - a light quantum, the name derived from the Greek "phos" meaning "light" and is the name given to hydrogen nucleus by Ernest Rutherford in 1920, from the Greek "protos" meaning "first". One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number. Quark – a fundamental particle that combines to form a range of other particles, including protons and neutrons, the particles that make up the atomic nucleus. The term was drawn from James Joyce's Finnegans Wake by American physicist Murray Gell-Mann in 1962.

Higgs boson - sometimes called the 'god particle' - proposed by Peter Higgs in 1964, is if it exists what gives matter mass. It has also been named the name God particle by American physicist Leon Lederman. Higgs told a newspaper that Leon "wanted to refer to it as that 'goddamn particle' and his editor wouldn't let him…" Scientists working at the world's biggest atom smasher near Geneva(CERN) have announced the discovery of a new subatomic particle that looks remarkably like the long-sought Higgs boson. Everything is made up of atoms, and inside atoms are electrons, protons and neutrons. They, in turn, are made of quarks and other subatomic particles. Scientists have long puzzled over how these minute building blocks of the universe acquire mass. Without mass, particles wouldn't hold together and there would be no matter. One theory proposed by British physicist Peter Higgs and teams in Belgium and the United States in the 1960s is that a new particle must be creating a "sticky" field that acts as a drag on other particles. The atom-smashing experiments at CERN have now captured a glimpse of what appears to be just such a Higgs-like particle. Boson - a class of particles often associated with forces (as the carriers of the force). They obey Bose-Einstein statistics, named after the Indian physicist, Satyendra Nath Bose. The suffix "-on" is Greek, and became standard for newly discovered particles a century ago. Since bosons with the same energy can occupy the same place in space, bosons are often force carrier particles. In contrast, fermions are usually associated with matter - although in quantum physics the distinction between the two concepts is not clear cut. Bosons may be either elementary, like photons, or composite, like mesons. Gluon - a type of boson responsible for the strong force between quarks. The term derives from the English word "glue". It was first proposed in 1962 by Murray Gell-Mann, who suggested the existence of particles composed of a number of gluons, which he called ‘glueballs’. Neutrino - uncharged particles created as a result of certain types of radioactive decay, with a tiny mass even by the standards of subatomic particles. Neutrino means "small neutral one" in Italian. The particle was first proposed by Wolfgang Pauli (1900-1958) in 1930, who gave it the name "neutron". Enrico Fermi renamed it three years later, because "neutron" (from the Latin for "neutral") had by then begun to be used to refer to the uncharged particle present in the atomic nucleus. Fermion - a class of particles, which, unlike bosons, obey Fermi-Dirac statistics. They are usually associated with matter rather than force. They are named after the Italian-born physicist Enrico Fermi, regarded as one of the fathers of the atomic bomb, along with Robert Oppenheimer. While most bosons are composite particles, in the Standard Model, there are six bosons, which are elementary: • The four gauge bosons (γ · g · Z · W±) • Higgs boson (H0) • Graviton (G). Meson - particle made of a quark and an anti-quark. The name comes from the Greek "meso" meaning "mid", because mesons, when first observed, appeared to have a mass somewhere between that of an electron, and nucleons (the particles - protons and neutrons - making up the atomic nucleus). Muon – Is one of a large number of particles named after letters of the Greek alphabet, in this case "mu". It was originally thought to be a type of meson (the mu meson, as distinct, say, from the pi meson), but was later renamed. Mesons came to be understood as particles made up of quarks, while muons are elementary particles. WIMP – are hypothetical particles serving as one possible solution to the dark matter problem. These particles interact through the weak force and gravity, and possibly through other interactions no stronger than the weak force. MACHO - Massive Astrophysical Compact Halo Object, or is a general name for any kind of astronomical body that might explain the apparent presence of dark matter in galaxy halos. Since MACHOs would not emit any light of their own, they would be very hard to detect. MACHOs may sometimes be black holes or neutron stars. Whimsically named as WIMPS came first!