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Chooz (experiment)
Chooz () was a short baseline neutrino oscillation experiment in Chooz, France. Its major result was setting limits on the neutrino oscillation parameters responsible for changing electron neutrinos into other neutrinos. Specifically, it found that for large δm2 and for maximal mixing. Results were published in 1999. The Double Chooz experiment continues to take data using the same lab space. Neutrino source Chooz used neutrinos from two pressurized water reactors, which provide a >99.999% source. The average neutrino energy was approximately 3 MeV, and the detector was roughly 1000 m from the reactor. The intensity was measured using both the heat balance and neutron output of the reactor, and was known to better than 2%. Detailed modeling of the reactor cores was used to predict both the intensity and energy spectrum of the neutrinos as a function of time. Neutrinos were observed via the inverse beta decay reaction ( + → + ). Detector The Chooz detector wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peeters (publishing Company)
Peeters Publishers is an international academic publisher founded in Leuven in 1857, joining a tradition of book printing in Leuven dating back to the 15th century. Peeters publishes 200 new titles and 75 journals a year. Humanities and social sciences are the main fields of the publishing house, with series focusing on Biblical studies, Religious studies, Patristics, Classical and Oriental studies, Egyptology, Philosophy, Ethics, Medieval studies, and the Arts. History Leuven’s association with printing is as old as the art of printing itself. In 1474 Johann Veldener, from Würzburg, Germany, prints the first book in Leuven. In the 15th century, eight printers were active in Leuven. The best known were Johann von Westphalen and Dirk Martens. In the 16th century it was mainly the Antwerp printers who published the important works of the humanists. The best-known Antwerp printer is undoubtedly Christoffel Plantin, who, due to the number of publications and its high qual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressurized Water Reactor
A pressurized water reactor (PWR) is a type of light-water reactor, light-water nuclear reactor. PWRs constitute the large majority of the world's nuclear power plants (with notable exceptions being the UK, Japan and Canada). In a PWR, the primary nuclear reactor coolant, coolant (water) is pumped under high pressure to the reactor core where it is heated by the energy released by the Nuclear fission, fission of atoms. The heated, high pressure water then flows to a Water-tube boiler, steam generator, where it transfers its thermal energy to lower pressure water of a secondary system where steam is generated. The steam then drives turbines, which spin an electric generator. In contrast to a boiling water reactor (BWR), pressure in the primary coolant loop prevents the water from boiling within the reactor. All light-water reactors use ordinary water as both coolant and neutron moderator. Most use anywhere from two to four vertically mounted steam generators; VVER reactors use horizo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Neutrino Problem
The solar neutrino problem concerned a large discrepancy between the flux of solar neutrinos as predicted from the Sun's luminosity and as measured directly. The discrepancy was first observed in the mid-1960s and was resolved around 2002. The flux of neutrinos at Earth is several tens of billions per square centimetre per second, mostly from the Sun's core. They are nevertheless hard to detect, because they interact very weakly with matter, traversing the whole Earth. Of the three types ( flavors) of neutrinos known in the Standard Model of particle physics, the Sun produces only electron neutrinos. When neutrino detectors became sensitive enough to measure the flow of electron neutrinos from the Sun, the number detected was much lower than predicted. In various experiments, the number deficit was between one half and two thirds. Particle physicists knew that a mechanism, discussed back in 1957 by Bruno Pontecorvo, could explain the deficit in electron neutrinos. However, they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pontecorvo–Maki–Nakagawa–Sakata Matrix
In particle physics, the Pontecorvo–Maki–Nakagawa–Sakata matrix (PMNS matrix), Maki–Nakagawa–Sakata matrix (MNS matrix), lepton mixing matrix, or neutrino mixing matrix is a unitary mixing matrix which contains information on the mismatch of quantum states of neutrinos when they propagate freely and when they take part in weak interactions. It is a model of neutrino oscillation. This matrix was introduced in 1962 by Ziro Maki, Masami Nakagawa, and Shoichi Sakata, to explain the neutrino oscillations predicted by Bruno Pontecorvo. The PMNS matrix The Standard Model of particle physics contains three generations or " flavors" of neutrinos, \nu_\mathrm, \nu_\mu, and \nu_\tau, each labeled with a subscript showing the charged lepton that it partners with in the charged-current weak interaction. These three eigenstates of the weak interaction form a complete, orthonormal basis for the Standard Model neutrino. Similarly, one can construct an eigenbasis out of three neu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photomultiplier
A photomultiplier is a device that converts incident photons into an electrical signal. Kinds of photomultiplier include: * Photomultiplier tube, a vacuum tube converting incident photons into an electric signal. Photomultiplier tubes (PMTs for short) are members of the class of vacuum tubes, and more specifically vacuum phototubes, which are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum. ** Magnetic photomultiplier, developed by the Soviets in the 1930s. ** Electrostatic photomultiplier, a kind of photomultiplier tube demonstrated by Jan Rajchman of RCA Laboratories in Princeton, NJ in the late 1930s which became the standard for all future commercial photomultipliers. The first mass-produced photomultiplier, the Type 931, was of this design and is still commercially produced today. * Silicon photomultiplier, a solid-state device converting incident photons into an electric signal. Silicon photomultiplie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gadolinium
Gadolinium is a chemical element with the symbol Gd and atomic number 64. Gadolinium is a silvery-white metal when oxidation is removed. It is only slightly malleable and is a ductile rare-earth element. Gadolinium reacts with atmospheric oxygen or moisture slowly to form a black coating. Gadolinium below its Curie point of is ferromagnetic, with an attraction to a magnetic field higher than that of nickel. Above this temperature it is the most paramagnetic element. It is found in nature only in an oxidized form. When separated, it usually has impurities of the other rare-earths because of their similar chemical properties. Gadolinium was discovered in 1880 by Jean Charles de Marignac, who detected its oxide by using spectroscopy. It is named after the mineral gadolinite, one of the minerals in which gadolinium is found, itself named for the Finnish chemist Johan Gadolin. Pure gadolinium was first isolated by the chemist Paul-Émile Lecoq de Boisbaudran around 1886. Gadoliniu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meter Water Equivalent
In physics, the meter water equivalent (often ''m.w.e.'' or ''mwe'') is a standard measure of cosmic ray attenuation in underground laboratories. A laboratory at a depth of 1000 m.w.e is shielded from cosmic rays equivalently to a lab below the surface of a body of water. Because laboratories at the same depth (in meters) can have greatly varied levels of cosmic ray penetration, the m.w.e. provides a convenient and consistent way of comparing cosmic ray levels in different underground locations. Cosmic ray attenuation is dependent on the density of the material of the overburden, so the m.w.e. is defined as the product of depth and density (also known as an interaction depth). Because the density of water is , of water gives an interaction depth of . Some publications use hg/cm² instead of m.w.e., although the two units are equivalent. For example, the Waste Isolation Pilot Plant, located deep in a salt formation, achieves 1585 m.w.e. shielding. Soudan Mine, at depth is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inverse Beta Decay
Inverse beta decay, commonly abbreviated to IBD, is a nuclear reaction involving an electron antineutrino scattering off a proton, creating a positron and a neutron. This process is commonly used in the detection of electron antineutrinos in neutrino detectors, such as the first detection of antineutrinos in the Cowan–Reines neutrino experiment, or in neutrino experiments such as KamLAND and Borexino. It is an essential process to experiments involving low-energy neutrinos (< 60 ) such as those studying neutrino oscillation, reactor neutrinos, |
Double Chooz
Double Chooz was a short-baseline neutrino oscillation experiment in Chooz, France. Its goal was to measure or set a limit on the ''θ''13 mixing angle, a neutrino oscillation parameter responsible for changing electron neutrinos into other neutrinos. The experiment uses reactors of the Chooz Nuclear Power Plant as a neutrino source and measures the flux of neutrinos they receive. To accomplish this, Double Chooz has a set of two detectors situated 400 meters and 1050 meters from the reactors. Double Chooz was a successor to the Chooz experiment; one of its detectors occupies the same site as its predecessor. Until January 2015 all data has been collected using only the far detector. The near detector was completed in September 2014, after construction delays, and started taking data at the beginning of 2015. Both detectors stopped taking data in late December 2017. Detector design Double Chooz used two identical gadolinium-doped liquid scintillator detectors placed in vicinity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Physical Journal C
The ''European Physical Journal C'' (''EPJ C'') is a biweekly peer-reviewed, open access scientific journal covering theoretical and experimental physics. It is part of the SCOAP3 initiative. See also * ''European Physical Journal The ''European Physical Journal'' (or ''EPJ'') is a joint publication of EDP Sciences, Springer Science+Business Media, and the Società Italiana di Fisica. It arose in 1998 as a merger and continuation of ''Acta Physica Hungarica'', '' Anales d ...'' References Physics journals Springer Science+Business Media academic journals Publications established in 1998 English-language journals Semi-monthly journals EDP Sciences academic journals Particle physics journals {{physics-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronvolt
In physics, an electronvolt (symbol eV, also written electron-volt and electron volt) is the measure of an amount of kinetic energy In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acc ... gained by a single electron accelerating from rest through an Voltage, electric potential difference of one volt in vacuum. When used as a Units of energy, unit of energy, the numerical value of 1 eV in joules (symbol J) is equivalent to the numerical value of the Electric charge, charge of an electron in coulombs (symbol C). Under the 2019 redefinition of the SI base units, this sets 1 eV equal to the exact value Historically, the electronvolt was devised as a standard unit of measure through its usefulness in Particle accelerator#Electrostatic particle accelerators, electrostatic particle accel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
