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Underwater telescope to study neutrinos

Posted by Hemos on from the to-study-space-go-underwater dept.

Darksky wrote to us with information about the proposed 'Antares' telescope. The proposal would be to put a telescope 2.4 kilometers underwater, in an attempt to study neutroino/cosmic rays. The telescope would use the the Earth as shield from cosmic rays, and hopefully study the muons liberated by the neutrinos.

5 of 117 comments (clear)

  1. Re:Hmmmm..... by Faramir · · Score: 3

    We can produce massive amounts of neutrinos. But it also takes massive amounts of work. I work on a project called MINOS--Main Injector Neutrino Oscillation Search. We will be shooting a beam of neutrinos (mainly muon type) from Fermilab outside of Chicago to northern Minnesota. At each end, we will look at the flux of each type of neutrino and compare the ratio of types. If the ratio is significantly different than 1, but the overall number of neutrino ratio between detectors is around 1, then this will indicate that neutrinos do indeed have mass. Cool project, but a little beside the point.

    Anyway, I've been touring the facilities the last few days, and I can tell you that the accelerator beamline is over 1 mile long, just to reach northern Minnesota. The two detectors, one on each side, will require abou 2,700 tons of steel each (no exaggeration!). So while a neutrino antenna may be able to use different (lower) energies than we are using, I can't imagine that the required equipment would be much different than this. More information can be found at U of Minnesota.

  2. Some further info on ANTARES by Aleatoric · · Score: 3

    Here are a couple of links to the antares site, with some more in depth information about the project.

    http://antares.in2p3.fr/antares/antares.html
    http://antares.in2p3.fr/antares/booklet/english/ intro_texte.html

    Here's a site with links to most of the other research involving neutrinos.

    http://www.phys.washington.edu/~superk/links.htm l

    --

    Nunc Tutus Exitus Computarus.

  3. SNO by Tekmage · · Score: 3

    The Sudbury Neutrino Observatory is a similar project - a sphere of heavy-water buried 2km underground.

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    --The more you know, the less you know.
  4. Re:who woulda thunk... by mph · · Score: 5
    The first solar neutrino detector was at the Homestake gold mine in Lead, South Dakota. It used perchloroethylene, a cleaning fluid, to provide chlorine which would be converted to argon in a reaction with neutrinos. You have to count the argon atoms periodically, so you don't get immediate notification of an event, nor good time resolution.

    Mont Blanc uses a liquid scintillator, which emits a flash when a neutrino event occurs. This approach has the advantage of providing immediate notification and good time resolution.

    The detector with the coolest name is Super Kamiokande, in Japan. It was originally designed to detect proton decay by observing the Cerenkov radiation from the fast electrons that would be a decay product, but it also can detect neutrinos. It also provides immediate notification and good time resolution.

    The most famous result from neutrino detectors is that the observations of the solar neutrino emission do not agree well with theoretical predictions.

    In addition to the detection of solar neutrinos, neutrino detectors also scored big-time by detecting the neutrino burst of supernova 1987a. Because neutrinos pass through just about anything, these observations were useful probes of what was happening at the center of the SN.

    Notes for a talk I gave in an undergrad class are available at http://wopr.caltech.edu/~mph/papers /neutrino.ps. References to other works are included.

  5. Hmm... by Enoch+Root · · Score: 3
    That's quite clever, for a number of reasons:

    The reason why water is used in radiation shielding is that it contains two Hydrogen atoms per water molecule. Since an atom of Hydrogen has more or less the same mass than a neutron, it acts like a billiard ball: the neutron tends to stop, and the proton is transferred all the kinetic energy. And since the proton is a charged particle, it stops quickly.

    Anyway; that means it's good shielding against neutrons. You still have neutrons coming from the environment ("thermal neutrons"), and if the telescope is exposed directly to water, this solves the problem. But you don't need to put it so far down underwater.

    Finally, gamma radiation: that's photons. how do you stop these? With difficulty, most of the times. Lead does it, but then lead also emits thermal neutrons! So you have to choose a way to stop both, which you can't.

    Except that at this depth, most of the gamma radiation coming from the Sun is absorbed already.

    It's a bit of an anti-Hubble: Hubble needs to be in space to be exposed to as much "noise" as possible, whereas this telescope needs to be shielded from almost everything.

    "There is no surer way to ruin a good discussion than to contaminate it with the facts."