Neutrinos Nobel Prizes for Neutrino Research
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Neutrinos Nobel prizes for neutrino research 1988: Leon M. Lederman, Melvin Schwartz and Jack Steinberger “for the neutrino beam method and the demonstration of the doublet structure of the leptons through the discovery of the muon neutrino” 1995: “for pioneering experimental contributions to lepton physics” Martin L. Perl “for the discovery of the tau lepton” Frederick Reines “for the detection of the neutrino” (work done in the early 1950s) 2002: Raymond Davis Jr. and Masatoshi Koshiba “for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos” 2015: Takaaki Kajita and Arthur B. McDonald “for the discovery of neutrino oscillations, which shows that neutrinos have mass” Neutrino production and detection The principle neutrino production in stars comes from proton (H+) fusion into alpha particles (He++): The neutrinos are produced when, for example, a diproton decays into a deuteron n ne W+ p e Neutron decay Proton-electron fusion Neutron à Proton + W- Proton à Neutron + W+ W- à Electron + Electron anti-neutrino W- + Electron à Electron neutrino Additional fusion reactions produce isotopes of Beryllium, Boron, and Lithium Read the short Wikipedia article, “Solar neutrino”: https://en.wikipedia.org/wiki/Solar_neutrino Neutrino astronomy Astronomical neutrino detectors • ANITA (airborne) • ANTARES (France, undersea northern complement to IceCube) • Auger (cosmic rays) • BDUNT: Baikal Deep Underwater Neutrino Telescope; mostly solar) • Borexino (solar neutrinos) • BUST (Baksan Underground Scintillation Telescope; early Soviet detector) • HALO (Helium and Lead Observatory, Sudbury, Ont., Part of SNEWS) • IceCube (Antarctica, 1 cubic km 1 mile under the ice) • LVD (Grand Sasso, SNEWS) • Super-Kamiokande (Japan, • SNEWS Astronomical • ANITA ANTARES Auger BDUNT Borexino BUST HALO IceCube LVD MARIACHI NEVOD SAGE Super-Kamiokande SNEWS Underwater neutrino telescopes: • DUMAND Project (1976–1995; cancelled) • Baikal Deep Underwater Neutrino Telescope (1993 on) • ANTARES (2006 on) • KM3NeT (future telescope; under construction since 2013) • NESTOR Project (under development since 1998) Under-ice neutrino telescopes: • AMANDA (1996–2009, superseded by IceCube) • IceCube (2004 on)[3] • DeepCore and PINGU, an existing extension and a proposed extension of IceCube Underground neutrino observatories: • Gran Sasso National Laboratories (LNGS), Italy, site of Borexino, CUORE, and other experiments. • Soudan Mine, home of Soudan 2, MINOS, and CDMS[14] • Kamioka Observatory, Japan • Underground Neutrino Observatory, Mont Blanc, France/Italy Miscellaneous: • GALLEX (1991–1997; ended) • Tauwer experiment (construction date to be determined) ANTARES is the name of a neutrino detector residing 2.5 km under the Mediterranean Sea off the coast of Toulon, France. It is designed to be used as a directional neutrino telescope to locate and observe neutrino flux from cosmic origins in the direction of the Southern Hemisphere of the Earth, a complement to the South Pole neutrino detector IceCube that detects neutrinos from both hemispheres. The name comes from Astronomy with a Neutrino Telescope and Abyss environmental RESearch project The IceCube Neutrino Observatory (or simply IceCube) is a neutrino observatory constructed at the Amundsen–Scott South Pole Station in Antarctica.[1] Its thousands of sensors are located under the Antarctic ice, distributed over a cubic kilometre. Super-Kamiokande • Cylindrical stainless steel tank about 40 m (131 ft) in height and diameter • 50,000 tons of ultrapure water ultrapure water • 13,000 photomultiplier tubes that detect light from Cherenkov radiation. Super Kamiokande observes no Day-Night variation in the 8B solar neutrino flux in 504 days of data and sees no significant zenith angle variations. (2) (PDF) Constraints on Neutrino Oscillation Parameters from the Measurement of Day-Night Solar Neutrino Fluxes at Super-Kamiokande. Available from: https://www.researchgate.net/publication/1985598_Constraints_on_Neutrino_Oscillation_Parameters_from_the_Measureme nt_of_Day-Night_Solar_Neutrino_Fluxes_at_Super-Kamiokande [accessed Jan 22 2019]. 8B Boron-8 neutrino flux: Boron-8, can beta+ decay into beryllium-8: This alternative boron-yielding reaction produces about 0.02% of the solar neutrinos; although so few that they would conventionally be neglected, these rare solar neutrinos stand out because of their higher average energies. The asterisk (*) on the beryllium-8 nucleus indicates that it is in an excited, unstable state. The excited beryllium-8 nucleus then splits into two helium-4 nuclei. Borexino is a particle physics experiment to study low energy (sub- MeV) solar neutrinos. The detector is the world's most radio-pure liquid scintillator calorimeter. It is placed within a stainless steel sphere which holds the signal detectors (photomultiplier tubes or PMTs) and is shielded by a water tank to protect it against external radiation and tag incoming cosmic muons that manage to penetrate the overburden of the mountain above. The primary aim of the experiment is to make a precise measurement of the individual neutrino fluxes from the Sun and compare them to the Standard solar model predictions. Laboratori Nazionali del Gran Sasso near the town of L'Aquila, Italy, and is supported by an international collaboration with researchers from Italy, the United States, Germany, France, Poland and Russia The Large Volume Detector (LVD) is a particle physics experiment situated in the Gran Sasso laboratory in Italy and is operated by the Italian Institute of Nuclear Physics (INFN). It has been in operation since June 1992, and is a member of the Supernova Early Warning System. Among other work, the detector should be able to detect neutrinos from our galaxy and possibly nearby galaxies.[1] The LVD uses 840 scintillator counters around a large tank of hydrocarbons.[2] The detector can detect both charged current and neutral current interactions.[2] The Helium And Lead Observatory (HALO) is a neutrino detector at SNOLab for the Supernova Early Warning System (SNEWS).[1] It began engineering operation on May 8, 2012,[2] and joined as an operational part of SNEWS in October 2015.[3][4] It was designed to be a low-cost, low-maintenance detector[5] with limited capabilities[6]:38 sufficient for the burst of neutrinos generated by a nearby supernova. When an electron neutrino collides with a lead nucleus, it causes a nuclear transmutation that ends with a neutron emission. Lead does not absorb neutrons readily since 208Pb it has a "magic number" of both protons and neutrons, so the neutrons pass through to the 3He detectors. If enough neutrons are detected in a short time, an alert is generated. ANITA Mysterious radio signals could be from new type of neutrino 17 Jul 2018 SNEWS: SuperNova Early Warning System The earliest signal to arrive at Earth from a supernova while be graviatational waves, followed within seconds by neutrinos. Light from the supernova should arrive within the next few hours. For this reason, neutrino detectors can provide an early warning system of a supernova, in time to watch for the light. There are currently seven neutrino detector members of SNEWS: • Borexino • Daya Bay • KamLAND • HALO • IceCube • LVD • Super-Kamiokande. SNEWS began operation prior to 2004, with three members (Super-Kamiokande, LVD, and SNO). The Sudbury Neutrino Observatory is no longer active as it is being upgraded to its successor program SNO+. The detectors send reports of a possible supernova to a computer at Brookhaven National Laboratory to identify a supernova. If the SNEWS computer identifies signals from two detectors within 10 seconds, the computer will send a supernova alert to observatories around the world to study the supernova.[3] The SNEWS mailing list is open-subscription, and the general public is allowed to sign up; however, the SNEWS collaboration encourages amateur astronomers to instead use Sky and Telescope magazine's AstroAlert service, which is linked to SNEWS. DUNE Deep Underground Neutrino Experiment Producing a neutrino beam: 1. Accelerate protons 2. Collide the protons with a graphite target 3. This produces neutrons, positive pions, and negative pions. 4. Use a magnetic horn to select the positive (negative) pions 5. Positive (negative) pions decay into (negative) positive muons and (anti-)neutrinos 6. A concrete and steel block absorbs the muons, leaving a neutrino beam or an anti-neutrino beam. The π± mesons have a mass of 139.6 MeV/c2 and a mean lifetime of 2.6033×10−8 s. They decay due to the weak interaction. The primary decay mode of a pion, with a branching fraction of 0.999877, is a leptonic decay into a muon and a muon neutrino The second most common decay mode of a pion, with a branching fraction of 0.000123, is also a leptonic decay into an electron and the corresponding electron antineutrino. This "electronic mode" was discovered at CERN in 1958. For a massless outgoing particle, parity would forbid the decay; the lighter the mass of the product particle, the rarer the decay becomes so the decay to a muon is much more likely than decay to an electron. http://www.dunescience.org http://vmsstreamer1.fnal.gov/OC/LBNFDUNE/index.htm https://www.youtube.com/watch?v=AYtKcZMJ_4c&feature=youtu.be .