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True Muonium
In particle physics, true muonium is a theoretically predicted exotic atom representing a bound state of an muon and an antimuon (μ+μ−). The existence of true muonium is well established theoretically within the Standard Model. Its properties within the Standard Model are determined by quantum electrodynamics, and may be modified by physics beyond the Standard Model. True muonium is yet to be observed experimentally, though it may have been produced in experiments involving collisions of electron and positron beams. The ortho-state of true muonium (i.e. the state with parallel alignment of the muon and antimuon spins) is expected to be relatively long-lived (with a lifetime of ), and decay predominantly to an e+e− pair, which makes it possible for LHCb experiment at CERN to observe it with the dataset collected by 2025. Experimental research There are several experimental projects searching for the true muonium. One of them is the μμ-tron experiment (Mumutron) planned ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Particle Physics
Particle physics or high-energy physics is the study of Elementary particle, fundamental particles and fundamental interaction, forces that constitute matter and radiation. The field also studies combinations of elementary particles up to the scale of protons and neutrons, while the study of combinations of protons and neutrons is called nuclear physics. The fundamental particles in the universe are classified in the Standard Model as fermions (matter particles) and bosons (force-carrying particles). There are three Generation (particle physics), generations of fermions, although ordinary matter is made only from the first fermion generation. The first generation consists of Up quark, 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. Quark, Quarks cannot exist on their own but form hadrons. Hadrons that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CERN
The European Organization for Nuclear Research, known as CERN (; ; ), is an intergovernmental organization that operates the largest particle physics laboratory in the world. Established in 1954, it is based in Meyrin, western suburb of Geneva, on the France–Switzerland border. It comprises #Member states and budget, 24 member states. Israel, admitted in 2013, is the only full member geographically out of Europe. CERN is an official United Nations General Assembly observers#Intergovernmental organizations, United Nations General Assembly observer. The acronym CERN is also used to refer to the laboratory; in 2023, it had 2,666 scientific, technical, and administrative staff members, and hosted about 12,370 users from institutions in more than 80 countries. In 2016, CERN generated 49 Byte#Multiple-byte units, petabytes of data. CERN's main function is to provide the particle accelerators and other infrastructure needed for high-energy physics research – consequently, numer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Onium
An onium (plural: onia) is a bound state of a particle and its antiparticle. These states are usually named by adding the suffix ''-onium'' to the name of one of the constituent particles (replacing an ''-on'' suffix when present), with one exception for " muonium"; a muon–antimuon bound pair is called " true muonium" to avoid confusion with old nomenclature. Examples Positronium is an onium which consists of an electron and a positron bound together as a long-lived metastable state. Positronium has been studied since the 1950s to understand bound states in quantum field theory. A recent development called non-relativistic quantum electrodynamics (NRQED) used this system as a proving ground. Pionium, a bound state of two oppositely charged pions, is interesting for exploring the strong interaction. This should also be true of protonium. The true analogs of positronium in the theory of strong interactions are the quarkonium states: they are mesons made of a heavy quark and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Positronium
Positronium (Ps) is a system consisting of an electron and its antimatter, anti-particle, a positron, bound together into an exotic atom, specifically an onium. Unlike hydrogen, the system has no protons. The system is unstable: the two particles annihilate each other to predominantly produce two or three gamma-rays, depending on the relative spin states. The energy levels of the two particles are similar to that of the hydrogen atom (which is a bound state of a proton and an electron). However, because of the reduced mass, the frequency, frequencies of the spectral lines are less than half of those for the corresponding hydrogen lines. States The mass of positronium is 1.022 MeV, which is twice the electron mass minus the binding energy of a few eV. The lowest energy orbital state of positronium is 1S, and like with hydrogen, it has a hyperfine structure arising from the relative orientations of the spins of the electron and the positron. The Singlet state, ''singlet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muonium
Muonium () is an exotic atom made up of an antimuon and an electron, which was discovered in 1960 by Vernon W. Hughes and is given the chemical symbol Mu. During the muon's lifetime, muonium can undergo chemical reactions. Description Because, like a proton, the antimuon's mass is vastly larger than that of the electron, muonium () is more similar to atomic hydrogen () than positronium (). Its Bohr radius and ionization energy are within 0.5% of hydrogen, deuterium, and tritium, and thus it can usefully be considered as an exotic light isotope of hydrogen. Properties Although muonium is short-lived, physical chemists study it using muon spin spectroscopy (μSR), a magnetic resonance technique analogous to nuclear magnetic resonance (NMR) or electron spin resonance (ESR) spectroscopy. Like ESR, μSR is useful for the analysis of chemical transformations and the structure of compounds with novel or potentially valuable electronic properties. Muonium is usually studied by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Super Charm-Tau Factory
Super Charm-Tau factory (SCT) is an electron–positron collider being designed and built by Budker Institute of Nuclear Physics in Novosibirsk. Its main goal is to study the CP-violation in the processes involving charmed hadrons, to investigate decays of the τ-lepton as well as to search for new forms of matter: glueballs, dark matter, etc. In the SCT the center of mass energy of colliding electrons and positrons will be 2–6 GeV while the luminosity will reach as high as . The electrons will be partially polarized. The synchrotron will be operating for 10 years. The particle registration and measurements will done using a universal high performance magnetic detector with the field strength of 1–1.5 Tesla. The SCT project is one Megascience class projects being built in Russia. See also *Beijing Electron–Positron Collider II The Beijing Electron–Positron Collider II (BEPC II) is a Chinese electron–positron collider, a type of particle accelerator, located i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Invariant Mass
The invariant mass, rest mass, intrinsic mass, proper mass, or in the case of bound systems simply mass, is the portion of the total mass of an object or system of objects that is independent of the overall motion of the system. More precisely, it is a characteristic of the system's total energy and momentum that is the same in all frames of reference related by Lorentz transformations.Lawrence S. LernerPhysics for Scientists and Engineers, Volume 2, page 1073 1997. If a center-of-momentum frame exists for the system, then the invariant mass of a system is equal to its total mass in that "rest frame". In other reference frames, where the system's momentum is non-zero, the total mass (a.k.a. relativistic mass) of the system is greater than the invariant mass, but the invariant mass remains unchanged. Because of mass–energy equivalence, the rest energy of the system is simply the invariant mass times the speed of light squared. Similarly, the total energy of the system is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collider
A collider is a type of particle accelerator that brings two opposing particle beams together such that the particles collide. Compared to other particle accelerators in which the moving particles collide with a stationary matter target, colliders can achieve higher collision energies. 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 extremely short 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 guiding them to colide with other par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siberian Branch Of The Russian Academy Of Sciences
The Siberian Branch of the Russian Academy of Sciences (SBRAS) was established by the Decree of the Government of the USSR which was based on the proposal of Mikhail Lavrentyev, Sergei Sobolev and Sergey Khristianovich in 1957 as a regional division of the Academy of Sciences of the USSR, replacing a previous small branch of the Academy of Sciences of the USSR. Novosibirsk State University was founded to serve as a staff base for the Siberian Branch. Lavrentyev was also the founding chairman of the branch. History During the war, hundreds of scientists were evacuated to Siberia, and in 1943 the West Siberian Branch (WSF) of the Soviet Union Academy of Sciences was created. Initially, the WSF allowed scientists to work in various cities. But since 1948, most scientists have been working in Novosibirsk. Formed in May 1957 on the initiative of academicians Mikhail Lavrentyev, Sergei Sobolev, and Sergey Khristianovich. When the department was organized, it included scien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Budker Institute Of Nuclear Physics
The Budker Institute of Nuclear Physics (BINP) is one of the major centres of advanced study of nuclear physics in Russia. It is located in the Siberian town Akademgorodok, on Academician Lavrentyev Avenue, Novosibirsk, Academician Lavrentiev Avenue. The institute was founded by Gersh Budker in 1959. Following his death in 1977, the institute was renamed in honour of Budker. Despite its name, the centre was not involved either with military atomic science or nuclear reactors instead, its concentration was on high-energy physics (particularly Plasma (physics), plasma physics) and particle physics. In 1961 the institute began building :ru:ВЭП-1, VEP-1,A. N. Skrinsly"Accelerator field development at Novosibirsk (history, status, prospects)", Particle Accelerator Conference, Proceedings of the 1995.V. N. Baier, "Forty years of acting electron-positron colliders"arXiv:hep-ph/0611201 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LHCb
The LHCb (Large Hadron Collider beauty) experiment is a particle physics detector collecting data at the Large Hadron Collider at CERN. LHCb specializes in the measurements of the parameters of CP violation in the interactions of b- and c-hadrons (heavy particles containing a bottom and charm quarks). Such studies can help to explain the matter-antimatter asymmetry of the Universe. The detector is also able to perform measurements of production cross sections, exotic hadron spectroscopy, and electroweak physics in the forward region. The LHCb collaborators, who built, operate and analyse data from the experiment, are composed of approximately 1650 people from 98 scientific institutes, representing 22 countries. Vincenzo Vagnoni succeeded on July 1, 2023 as spokesperson for the collaboration from Chris Parkes (spokesperson 2020–2023). The experiment is located at point 8 on the LHC tunnel close to Ferney-Voltaire, France just over the border from Geneva. The (small) MoEDA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exotic Atom
An exotic atom is an otherwise normal atom in which one or more sub-atomic particles have been replaced by other particles. For example, electrons may be replaced by other negatively charged particles such as muons (muonic atoms) or pions (pionic atoms). Because these substitute particles are usually unstable, exotic atoms typically have very short lifetimes and no exotic atom observed so far can persist under normal conditions. Muonic atoms In a ''muonic atom'' (previously called a ''mu-mesic'' atom, now known to be a misnomer as muons are not mesons), an electron is replaced by a muon, which, like the electron, is a lepton. Since leptons are only sensitive to weak, electromagnetic and gravitational forces, muonic atoms are governed to very high precision by the electromagnetic interaction. Since a muon is more massive than an electron, the Bohr orbits are closer to the nucleus in a muonic atom than in an ordinary atom, and corrections due to quantum electrodynamics are more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
