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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 (Myumutron) pla ... [...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] |
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. Publications The Siberian branch publishes two journals — '' Archaeology, Ethnology & Anthropology of Eurasia'' and ''Geography and Natural Resource'' — in association with Elsevier Elsevier () is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell'', the ScienceDirect collection of electronic journals, '' Trends'', th .... References 1957 establishments in ... [...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 antiqua ... [...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. Due to the mass difference between the antimuon and 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. 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 muon spin rotation, in which the Mu atom's spin prec ... [...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 *Belle II *PANDA experiment The PANDA experiment is a planned particle physics experiment at the Facility for Antiproton and Ion Research in Da ... [...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 nonzero, 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 its tot ... [...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] |
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 Lavrentiev Avenue. The institute was founded by Gersh Budker in 1959. Following his death in 1977, the institute was renamed in honour of Academician 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) and particle physics. In 1961 the institute began building 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] |
Exotic Atom
An exotic atom is an otherwise normal atom in which one or more sub-atomic particles have been replaced by other particles of the same charge. For example, electrons may be replaced by other negatively charged particles such as muons (muonic atoms) or pions (pionic atoms).Exotic atoms , AccessScience, McGraw-Hill. accessdate=September 26, 2007. 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 muon ...
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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 a northwestern suburb of Geneva, on the France–Switzerland border. It comprises 23 member states, and Israel (admitted in 2013) is currently the only non-European country holding full membership. CERN is an official United Nations General Assembly observer. The acronym CERN is also used to refer to the laboratory; in 2019, it had 2,660 scientific, technical, and administrative staff members, and hosted about 12,400 users from institutions in more than 70 countries. In 2016, CERN generated 49 petabytes of data. CERN's main function is to provide the particle accelerators and other infrastructure needed for high-energy physics research — consequently, numerous experiments have been constructed at CERN through international collaborations. CERN is the site of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LHCb
The LHCb (Large Hadron Collider beauty) experiment is one of eight particle physics detector experiments collecting data at the Large Hadron Collider at CERN. LHCb is a specialized b-physics experiment, designed primarily to measure the parameters of CP violation in the interactions of b-hadrons (heavy particles containing a bottom quark). 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, charm physics and electroweak physics in the forward region. The LHCb collaboration, who built, operate and analyse data from the experiment, is composed of approximately 1260 people from 74 scientific institutes, representing 16 countries. Chris Parkes succeeded on July 1, 2020 as spokesperson for the collaboration to Giovanni Passaleva (spokesperson 2017-2020). The experiment is located at point 8 on the LHC tunnel close to Ferney-Voltaire, France just o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
