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SNOLAB 2014-03-21
SNOLAB is a Canadian underground science laboratory specializing in neutrino and dark matter physics. Located 2 km below the surface in Vale's Creighton nickel mine near Sudbury, Ontario, SNOLAB is an expansion of the existing facilities constructed for the original Sudbury Neutrino Observatory (SNO) solar neutrino experiment. SNOLAB is the world's deepest operational clean room facility. Although accessed through an active mine, the laboratory proper is maintained as a class-2000 cleanroom, with very low levels of dust and background radiation. SNOLAB's 2070 m (6800 feet) of overburden rock provides 6010 metre water equivalent (MWE) shielding from cosmic rays, providing a low-background environment for experiments requiring high sensitivities and extremely low counting The combination of great depth and cleanliness that SNOLAB affords allows extremely rare interactions and weak processes to be studied. In addition to neutrino and dark matter physics, SNOLAB is also host to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SNOLAB 2014-03-21
SNOLAB is a Canadian underground science laboratory specializing in neutrino and dark matter physics. Located 2 km below the surface in Vale's Creighton nickel mine near Sudbury, Ontario, SNOLAB is an expansion of the existing facilities constructed for the original Sudbury Neutrino Observatory (SNO) solar neutrino experiment. SNOLAB is the world's deepest operational clean room facility. Although accessed through an active mine, the laboratory proper is maintained as a class-2000 cleanroom, with very low levels of dust and background radiation. SNOLAB's 2070 m (6800 feet) of overburden rock provides 6010 metre water equivalent (MWE) shielding from cosmic rays, providing a low-background environment for experiments requiring high sensitivities and extremely low counting The combination of great depth and cleanliness that SNOLAB affords allows extremely rare interactions and weak processes to be studied. In addition to neutrino and dark matter physics, SNOLAB is also host to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laboratory
A laboratory (; ; colloquially lab) is a facility that provides controlled conditions in which scientific or technological research, experiments, and measurement may be performed. Laboratory services are provided in a variety of settings: physicians' offices, clinics, hospitals, and regional and national referral centers. Overview The organisation and contents of laboratories are determined by the differing requirements of the specialists working within. A physics laboratory might contain a particle accelerator or vacuum chamber, while a metallurgy laboratory could have apparatus for casting or refining metals or for testing their strength. A chemist or biologist might use a wet laboratory, while a psychologist's laboratory might be a room with one-way mirrors and hidden cameras in which to observe behavior. In some laboratories, such as those commonly used by computer scientists, computers (sometimes supercomputers) are used for either simulations or the analysis of data. Scient ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carleton University
Carleton University is an English-language public research university in Ottawa, Ontario, Canada. Founded in 1942 as Carleton College, the institution originally operated as a private, non-denominational evening college to serve returning World War II veterans. Carleton was chartered as a university by the provincial government in 1952 through ''The Carleton University Act,'' which was then amended in 1957, giving the institution its current name. The university is named for the now-dissolved Carleton County, which included the city of Ottawa at the time the university was founded. Carleton County, in turn, was named in honour of Guy Carleton, 1st Baron Dorchester, who was Governor General of The Canadas from 1786 to 1796. The university moved to its current campus in 1959, growing rapidly in size during the 1960s as the Ontario government increased support for post-secondary institutions and expanded access to higher education. Carleton offers a diverse range of academic program ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DEAP
DEAP (Dark matter Experiment using Argon Pulse-shape discrimination) is a direct dark matter search experiment which uses liquid argon as a target material. DEAP utilizes background discrimination based on the characteristic scintillation pulse-shape of argon. A first-generation detector (DEAP-1) with a 7 kg target mass was operated at Queen's University to test the performance of pulse-shape discrimination at low recoil energies in liquid argon. DEAP-1 was then moved to SNOLAB, 2 km below Earth's surface, in October 2007 and collected data into 2011. DEAP-3600 was designed with 3600 kg of active liquid argon mass to achieve sensitivity to WIMP-nucleon scattering cross-sections as low as 10−46 cm2 for a dark matter particle mass of 100 GeV/c2. The DEAP-3600 detector finished construction and began data collection in 2016. An incident with the detector forced a short pause in the data collection in 2016. As of 2019, the experiment is collecting data. To reac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dark Matter
Dark matter is a hypothetical form of matter thought to account for approximately 85% of the matter in the universe. Dark matter is called "dark" because it does not appear to interact with the electromagnetic field, which means it does not absorb, reflect, or emit electromagnetic radiation and is, therefore, difficult to detect. Various astrophysical observationsincluding gravitational effects which cannot be explained by currently accepted theories of gravity unless more matter is present than can be seenimply dark matter's presence. For this reason, most experts think that dark matter is abundant in the universe and has had a strong influence on its structure and evolution. The primary evidence for dark matter comes from calculations showing that many galaxies would behave quite differently if they did not contain a large amount of unseen matter. Some galaxies would not have formed at all and others would not move as they currently do. Other lines of evidence include observa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charge-coupled Device
A charge-coupled device (CCD) is an integrated circuit containing an array of linked, or coupled, capacitors. Under the control of an external circuit, each capacitor can transfer its electric charge to a neighboring capacitor. CCD sensors are a major technology used in digital imaging. In a CCD image sensor, pixels are represented by p-doped metal–oxide–semiconductor (MOS) capacitors. These MOS capacitors, the basic building blocks of a CCD, are biased above the threshold for inversion when image acquisition begins, allowing the conversion of incoming photons into electron charges at the semiconductor-oxide interface; the CCD is then used to read out these charges. Although CCDs are not the only technology to allow for light detection, CCD image sensors are widely used in professional, medical, and scientific applications where high-quality image data are required. In applications with less exacting quality demands, such as consumer and professional digital cameras, act ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernovae
A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when a white dwarf is triggered into runaway nuclear fusion. The original object, called the ''progenitor'', either collapses to a neutron star or black hole, or is completely destroyed. The peak optical luminosity of a supernova can be comparable to that of an entire galaxy before fading over several weeks or months. Supernovae are more energetic than novae. In Latin, ''nova'' means "new", referring astronomically to what appears to be a temporary new bright star. Adding the prefix "super-" distinguishes supernovae from ordinary novae, which are far less luminous. The word ''supernova'' was coined by Walter Baade and Fritz Zwicky in 1929. The last supernova to be directly observed in the Milky Way was Kepler's Supernova in 1604, appearing not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helium And Lead Observatory
The Helium And Lead Observatory (HALO) is a neutrino detector at SNOLab for the Supernova Early Warning System (SNEWS). It began engineering operation on May 8, 2012, and joined as an operational part of SNEWS in October 2015. It was designed to be a low-cost, low-maintenance detector with limited capabilities sufficient for the burst of neutrinos generated by a nearby supernova. Its major components are left over from other decommissioned experiments: 76 tons of lead from an earlier cosmic-ray experiment, and 128 three-metre-long helium-3 neutron detectors from the Sudbury Neutrino Observatory. The idea of using lead to detect supernova neutrinos was originally proposed in 1996 by Cliff Hargrove as the "lead astronomical neutrino detector" (LAND), and in 2004, Charles Duba, then a PhD student working on SNO, proposed re-using them for this purpose, prompting the renaming to HALO. Design of the current detector began in 2007. When an electron neutrino collides with a lead nucl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double Beta Decay
In nuclear physics, double beta decay is a type of radioactive decay in which two neutrons are simultaneously transformed into two protons, or vice versa, inside an atomic nucleus. As in single beta decay, this process allows the atom to move closer to the optimal ratio of protons and neutrons. As a result of this transformation, the nucleus emits two detectable beta particles, which are electrons or positrons. The literature distinguishes between two types of double beta decay: ''ordinary'' double beta decay and ''neutrinoless'' double beta decay. In ordinary double beta decay, which has been observed in several isotopes, two electrons and two electron antineutrinos are emitted from the decaying nucleus. In neutrinoless double beta decay, a hypothesized process that has never been observed, only electrons would be emitted. History The idea of double beta decay was first proposed by M. Goeppert-Mayer in 1935. In 1937, E. Majorana demonstrated that all results of beta decay ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Alkyl Benzene
Linear alkylbenzenes (sometimes also known as LABs) are a family of organic compounds with the formula C6H5CnH2n+1. Typically, ''n'' lies between 10 and 16, although generally supplied as a tighter cut, such as C12-C15, C12-C13 and C10-C13, for detergent use. The CnH2n+1 chain is unbranched. They are mainly produced as intermediate in the production of surfactants, for use in detergent. Since the 1960s, LABs have emerged as the dominant precursor of biodegradable detergents. Production Hydrotreated kerosene is a typical feedstock for high purity linear paraffins (n-paraffins), which are subsequently dehydrogenated to linear olefins: :CnH2n+2 → CnH2n + H2 Alternatively, ethylene can be oligomerized (partially polymerized) to produce linear alkenes. The resulting linear mono-olefins react with benzene in the presence of a catalyst to produce the LABs. Hydrogen fluoride (HF) and aluminium chloride (AlCl3) are the two major catalysts for the alkylation of benzene with linea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutrino
A neutrino ( ; denoted by the Greek letter ) is a fermion (an elementary particle with spin of ) that interacts only via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass is so small ('' -ino'') that it was long thought to be zero. The rest mass of the neutrino is much smaller than that of the other known elementary particles excluding massless particles. The weak force has a very short range, the gravitational interaction is extremely weak due to the very small mass of the neutrino, and neutrinos do not participate in the strong interaction. Thus, neutrinos typically pass through normal matter unimpeded and undetected. Weak interactions create neutrinos in one of three leptonic flavors: electron neutrinos muon neutrinos (), or tau neutrinos (), in association with the corresponding charged lepton. Although neutrinos were long believed to be massless, it is now known that there are three discrete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SNO+
SNO+ is a physics experiment designed to search for neutrinoless double beta decay, with secondary measurements of proton–electron–proton (''pep'') solar neutrinos, geoneutrinos from radioactive decays in the Earth, and reactor neutrinos. It is under construction (as of February 2017) using the underground equipment already installed for the former Sudbury Neutrino Observatory (SNO) experiment at SNOLAB. It could also observe supernovae neutrinos if a supernova occurs in our galaxy. Physics goals The primary goal of the SNO+ detector is the search for neutrinoless double beta decay, specifically with regard to decay of , to understand if a neutrino is its own anti-particle (i.e. a majorana fermion). Secondary physics goals include measurement of neutrinos or antineutrinos from: * Proton-electron-proton (pep) and carbon-nitrogen-oxygen (CNO) cycles within the Sun to better understand neutrino-matter interaction and solar composition. * Beta decay of uranium and thorium wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
