Project DUMAND
Encyclopedia
The DUMAND Project was a proposed underwater neutrino telescope to be built in the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...

, off the shore of the island of Hawaii
Hawaii (island)
The Island of Hawaii, also called the Big Island or Hawaii Island , is a volcanic island in the North Pacific Ocean...

, five kilometers beneath the surface. It would have included thousands of strings of instruments occupying a cubic kilometer of the ocean
Ocean
An ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.More than half of this area is over 3,000...

.
The proposal called for two types of detectors: optical detectors to find the Cherenkov radiation
Cherenkov radiation
Cherenkov radiation is electromagnetic radiation emitted when a charged particle passes through a dielectric medium at a speed greater than the phase velocity of light in that medium...

 emitted by proton
Proton
The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number....

s traveling at more than 75% of the speed of light
Speed of light
The speed of light in vacuum, usually denoted by c, is a physical constant important in many areas of physics. Its value is 299,792,458 metres per second, a figure that is exact since the length of the metre is defined from this constant and the international standard for time...

 as a result of collision by neutrino
Neutrino
A neutrino is an electrically neutral, weakly interacting elementary subatomic particle with a half-integer spin, chirality and a disputed but small non-zero mass. It is able to pass through ordinary matter almost unaffected...

s, and hydrophone
Hydrophone
A hydrophone is a microphone designed to be used underwater for recording or listening to underwater sound. Most hydrophones are based on a piezoelectric transducer that generates electricity when subjected to a pressure change...

s to listen for the acoustic signals generated by the fast-moving protons. Sophisticated signal processing
Signal processing
Signal processing is an area of systems engineering, electrical engineering and applied mathematics that deals with operations on or analysis of signals, in either discrete or continuous time...

 would have combined the signals from many optical and acoustic sensors, allowing scientists to determine the direction from which the neutrino arrived, and to rule out false signals arising from other particles
Subatomic particle
In physics or chemistry, subatomic particles are the smaller particles composing nucleons and atoms. There are two types of subatomic particles: elementary particles, which are not made of other particles, and composite particles...

 or acoustic sources. Because of the nature of the interaction
Weak interaction
Weak interaction , is one of the four fundamental forces of nature, alongside the strong nuclear force, electromagnetism, and gravity. It is responsible for the radioactive decay of subatomic particles and initiates the process known as hydrogen fusion in stars...

 between neutrinos and protons, DUMAND would have been most sensitive to ultra-high energy neutrinos, and completely insensitive to solar neutrino
Solar neutrino
Electron neutrinos are produced in the Sun as a product of nuclear fusion. By far the largest fraction of neutrinos passing through the Earth are Solar neutrinos....

s.

Work began in about 1976, at Keahole Point
Keahole Point
Keāhole Point is the westernmost point of the island of Hawaii. The Kona International Airport was moved here from directly north of the town of Kailua-Kona in 1970, when the previous smaller airstrip was converted into the Old Kona Airport State Recreation Area...

, but the project cancelled in 1995 due to technical difficulties. Although it was never completed, DUMAND was in a sense a precursor of the Antarctic Muon And Neutrino Detector Array
Antarctic Muon And Neutrino Detector Array
The Antarctic Muon And Neutrino Detector Array is a neutrino telescope located beneath the Amundsen-Scott South Pole Station. In 2005, after nine years of operation, AMANDA officially became part of its successor project, the IceCube Neutrino Observatory.AMANDA consists of optical modules, each...

 (AMANDA), and the water Cherenkov neutrino telescopes in the Mediterranean (ANTARES
ANTARES (telescope)
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...

, NEMO and the NESTOR Project
Nestor Project
The NESTOR Project is an international scientific collaboration whose target is the deployment of a neutrino telescope on the sea floor off Pylos, Greece.-Neutrino:...

). The DUMAND hardware was also donated to NESTOR, to reduce costs and cut on development and construction time.
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