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Sakata Model
In particle physics, the Sakata model of hadrons was a precursor to the quark model. It proposed that the proton, neutron, and Lambda baryon were elementary particles (sometimes referred to as sakatons ), and that all other known hadrons were made of them. The model was proposed by Shoichi Sakata in 1956. The model was successful in explaining many features of hadrons, but was supplanted by the quark model as the understanding of hadrons progressed. Overview The success of the Sakata model is due to the fact that there is a correspondence between the proton, neutron, and Lambda baryon The lambda baryons (Λ) are a family of subatomic hadron particles containing one up quark, one down quark, and a third quark from a higher flavour generation, in a combination where the quantum wave function changes sign upon the flavour of any ..., and the up, down, and strange quarks. The proton contains two up quarks and a down quark, the neutron contains one up quark and two down quarks, wh ... [...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] |
Quark Model
In particle physics, the quark model is a classification scheme for hadrons in terms of their valence quarks—the quarks and antiquarks which give rise to the quantum numbers of the hadrons. The quark model underlies "flavor SU(3)", or the Eightfold Way, the successful classification scheme organizing the large number of lighter hadrons that were being discovered starting in the 1950s and continuing through the 1960s. It received experimental verification beginning in the late 1960s and is a valid effective classification of them to date. The model was independently proposed by physicists Murray Gell-Mann, who dubbed them "quarks" in a concise paper, and George Zweig, who suggested "aces" in a longer manuscript. André Petermann also touched upon the central ideas from 1963 to 1965, without as much quantitative substantiation. Today, the model has essentially been absorbed as a component of the established quantum field theory of strong and electroweak particle interactions, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proton
A proton is a stable subatomic particle, symbol , H+, or 1H+ with a positive electric charge of +1 ''e'' elementary charge. Its mass is slightly less than that of a neutron and 1,836 times the mass of an electron (the proton–electron mass ratio). Protons and neutrons, each with masses of approximately one atomic mass unit, are jointly referred to as "nucleons" (particles present in atomic nuclei). One or more protons are present in the nucleus of every atom. They provide the attractive electrostatic central force which binds the atomic electrons. The number of protons in the nucleus is the defining property of an element, and is referred to as the atomic number (represented by the symbol ''Z''). Since each element has a unique number of protons, each element has its own unique atomic number, which determines the number of atomic electrons and consequently the chemical characteristics of the element. The word ''proton'' is Greek for "first", and this name was given to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutron
The neutron is a subatomic particle, symbol or , which has a neutral (not positive or negative) charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons behave similarly within the nucleus, and each has a mass of approximately one atomic mass unit, they are both referred to as nucleons. Their properties and interactions are described by nuclear physics. Protons and neutrons are not elementary particles; each is composed of three quarks. The chemical properties of an atom are mostly determined by the configuration of electrons that orbit the atom's heavy nucleus. The electron configuration is determined by the charge of the nucleus, which is determined by the number of protons, or atomic number. The number of neutrons is the neutron number. Neutrons do not affect the electron configuration, but the sum of atomic and neutron numbers is the mass of the nucleus. Atoms of a chemical element t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lambda Baryon
The lambda baryons (Λ) are a family of subatomic hadron particles containing one up quark, one down quark, and a third quark from a higher flavour generation, in a combination where the quantum wave function changes sign upon the flavour of any two quarks being swapped (thus slightly different from a neutral sigma baryon, ). They are thus baryons, with total isospin of 0, and have either neutral electric charge or the elementary charge +1. Overview The lambda baryon was first discovered in October 1950, by V. D. Hopper and S. Biswas of the University of Melbourne, as a neutral V particle with a proton as a decay product, thus correctly distinguishing it as a baryon, rather than a meson, i.e. different in kind from the K meson discovered in 1947 by Rochester and Butler; they were produced by cosmic rays and detected in photographic emulsions flown in a balloon at . Though the particle was expected to live for , it actually survived for . The property that caused it to live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progress Of Theoretical Physics Supplement
''Progress of Theoretical and Experimental Physics'' (PTEP) is a monthly peer-reviewed scientific journal published by Oxford University Press on behalf of the Physical Society of Japan. It was established as ''Progress of Theoretical Physics'' in July 1946 by Hideki Yukawa was a Japanese theoretical physicist and the first Japanese Nobel laureate for his prediction of the pi meson, or pion. Biography He was born as Hideki Ogawa in Tokyo and grew up in Kyoto with two older brothers, two older sisters, and two yo ... and obtained its current name in January 2013. ''Progress of Theoretical and Experimental Physics'' is part of the SCOAP3 initiative. References External links * Physics journals English-language journals Publications established in 1946 Theoretical physics Monthly journals Oxford University Press academic journals Open access journals Particle physics journals {{physics-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shoichi Sakata
was a Japanese physicist and Marxist who was internationally known for theoretical work on the subatomic particles.Nussbaum, Louis-Frédéric. (2005). "''Sakata Shōichi''" in ; n.b., Louis-Frédéric is pseudonym of Louis-Frédéric Nussbaum, ''see'Deutsche Nationalbibliothek Authority File. He proposed the two meson theory, the Sakata model (an early precursor to the quark model), and the Pontecorvo–Maki–Nakagawa–Sakata neutrino mixing matrix. After the end of World War II, he joined other physicists in campaigning for the peaceful uses of nuclear power. Life and career Early life and education Sakata was born in Tokyo, Japan on January 18, 1911, to a family that held a tradition of public service. He was the eldest of six children of Tatsue Sakata and . At the time of Sakata's birth, Mikita was secretary to Prime Minister Katsura Tarō, who became Sakata's godfather. While attending Kōnan Middle School in Hyōgo Prefecture in 1924, Sakata was taught by the physicist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progress Of Theoretical Physics
''Progress of Theoretical and Experimental Physics'' (PTEP) is a monthly peer-reviewed scientific journal published by Oxford University Press on behalf of the Physical Society of Japan. It was established as ''Progress of Theoretical Physics'' in July 1946 by Hideki Yukawa was a Japanese theoretical physicist and the first Japanese Nobel laureate for his prediction of the pi meson, or pion. Biography He was born as Hideki Ogawa in Tokyo and grew up in Kyoto with two older brothers, two older sisters, and two yo ... and obtained its current name in January 2013. ''Progress of Theoretical and Experimental Physics'' is part of the SCOAP3 initiative. References External links * Physics journals English-language journals Publications established in 1946 Theoretical physics Monthly journals Oxford University Press academic journals Open access journals Particle physics journals {{physics-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Up Quark
The up quark or u quark (symbol: u) is the lightest of all quarks, a type of elementary particle, and a significant constituent of matter. It, along with the down quark, forms the neutrons (one up quark, two down quarks) and protons (two up quarks, one down quark) of atomic nuclei. It is part of the first generation of matter, has an electric charge of + ''e'' and a bare mass of . Like all quarks, the up quark is an elementary fermion with spin , and experiences all four fundamental interactions: gravitation, electromagnetism, weak interactions, and strong interactions. The antiparticle of the up quark is the up antiquark (sometimes called ''antiup quark'' or simply ''antiup''), which differs from it only in that some of its properties, such as charge have equal magnitude but opposite sign. Its existence (along with that of the down and strange quarks) was postulated in 1964 by Murray Gell-Mann and George Zweig to explain the Eightfold Way classification scheme of had ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Down Quark
The down quark or d quark (symbol: d) is the second-lightest of all quarks, a type of elementary particle, and a major constituent of matter. Together with the up quark, it forms the neutrons (one up quark, two down quarks) and protons (two up quarks, one down quark) of atomic nuclei. It is part of the first generation of matter, has an electric charge of − ''e'' and a bare mass of . Like all quarks, the down quark is an elementary fermion with spin , and experiences all four fundamental interactions: gravitation, electromagnetism, weak interactions, and strong interactions. The antiparticle of the down quark is the down antiquark (sometimes called ''antidown quark'' or simply ''antidown''), which differs from it only in that some of its properties have equal magnitude but opposite sign. Its existence (along with that of the up and strange quarks) was postulated in 1964 by Murray Gell-Mann and George Zweig to explain the Eightfold Way classification scheme of hadro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strange Quark
The strange quark or s quark (from its symbol, s) is the third lightest of all quarks, a type of elementary particle. Strange quarks are found in subatomic particles called hadrons. Examples of hadrons containing strange quarks include kaons (), strange D mesons (), Sigma baryons (), and other strange particles. According to the IUPAP, the symbol s is the official name, while "strange" is to be considered only as a mnemonic. The name sideways has also been used because the s quark has an I value of 0 while the u ("up") and d ("down") quarks have values of + and − respectively. Along with the charm quark, it is part of the second generation of matter. It has an electric charge of − ''e'' and a bare mass of . Like all quarks, the strange quark is an elementary fermion with spin , and experiences all four fundamental interactions: gravitation, electromagnetism, weak interactions, and strong interactions. The antiparticle of the strange quark is the strange ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SU(3)
In mathematics, the special unitary group of degree , denoted , is the Lie group of unitary matrices with determinant 1. The more general unitary matrices may have complex determinants with absolute value 1, rather than real 1 in the special case. The group operation is matrix multiplication. The special unitary group is a normal subgroup of the unitary group , consisting of all unitary matrices. As a compact classical group, is the group that preserves the standard inner product on \mathbb^n. It is itself a subgroup of the general linear group, \operatorname(n) \subset \operatorname(n) \subset \operatorname(n, \mathbb ). The groups find wide application in the Standard Model of particle physics, especially in the electroweak interaction and in quantum chromodynamics. The groups are important in quantum computing, as they represent the possible quantum logic gate operations in a quantum circuit with n qubits and thus 2^n basis states. (Alternatively, the more general ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
