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Science

Low-Energy Neutrinos Detected In Real Time 73

Posted by kdawson from the tell-me-why-the-stars-do-shine dept.
Roland Piquepaille sends us word of first results from the Borexino detector in Italy, where an international team of more than 100 researchers has detected low-energy solar neutrinos for the first time. These results confirm recent "theories about the nature of neutrinos and the inner workings of the sun and other stars." In particular, it's now almost certain that neutrinos oscillate among three types, namely electron, muon, and tau neutrinos. The Borexino detector lies almost a mile underground near L'Aquila, Italy, and it sets new standards in the purity of the materials used in its construction.
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Low-Energy Neutrinos Detected In Real Time More

Low-Energy Neutrinos Detected In Real Time

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  • Neutrinos (Score:5, Informative)

    by the_kanzure ( 1100087 ) on Monday August 27, 2007 @07:19AM (#20370225) Homepage
    * Neutrino [wikipedia.org]
    * History of the neutrinos [in2p3.fr] [from our perspective, mind you]
    * The Ultimate Neutrino Page [cupp.oulu.fi]
    etc. I should go call up my particle physicist body to post up some comments. :)

  • The paper (Score:5, Informative)

    by Angstroman ( 747480 ) on Monday August 27, 2007 @07:24AM (#20370251)
    For those interested, the paper itself can be found at http://arxiv.org/abs/0708.2251v1 [arxiv.org]. The team is detecting neutrinos from Be 7 at the rate of 47 per day.

    • Some basic papers (Score:5, Informative)

      by the_kanzure ( 1100087 ) on Monday August 27, 2007 @07:35AM (#20370321) Homepage
      TASI 2002 lectures on neutrinos [arxiv.org] [Yuval Grossman] [PDF]:

      We present a pedagogical review of neutrino physics. In the first lecture we describe the theoretical motivation for neutrino masses, and explain how neutrino flavor oscillation experiments can probe neutrino masses. In the second lecture we review the experimental data, and show that it is best explained if neutrinos are massive. In the third lecture we explain what are the theoretical implications of the data, in particular, what are the challenges they impose on models of physics beyond the SM. We give examples of theoretical models that cop e with some of these challenges.
      Neutrino physics [arxiv.org] [Evgeny Khakimovich Akhmedov] [PDF]:

      In the present lectures the following topics are considered: general properties of neutrinos, neutrino mass phenomenology (Dirac and Majorana masses), neutrino masses in the simplest extensions of the standard model (including the seesaw mechanism), neutrino oscillations in vacuum, neutrino oscillations in matter (the MSW effect) in 2- and 3-flavour schemes, implications of CP, T and CPT symmetries for neutrino oscillations, double beta decay, solar neutrino oscillations and the solar neutrino problem, and atmospheric neutrinos. We also give a short overview of the results of the accelerator and reactor neutrino experiments and of future projects. Finally, we discuss how the available experimental data on neutrino masses and lepton mixing can be summarized in the phenomenologically allowed forms of the neutrino mass matrix.
      BTW, particle physics has an awesome WWW presence.

      • Re:Some basic papers (Score:5, Funny)

        by sholden ( 12227 ) on Monday August 27, 2007 @07:43AM (#20370353) Homepage

        BTW, particle physics has an awesome WWW presence.

        It's almost as if the world's largest particle physics laboratory had something to do with creating it.

        Spooky!

        • Re: (Score:2, Funny)

          by sayfawa ( 1099071 )
          Al Gore is a particle physicist?

          • Re:Some basic papers (Score:4, Funny)

            by MyLongNickName ( 822545 ) on Monday August 27, 2007 @08:03AM (#20370457) Journal
            Al Gore INVENTED particles.
            • OK, not on topic but it did make me chuckle.
            • And Dubya says that the jury is still out on the existence of particles. But don't worry; Halliburton just got a rocket contract, so Cheney is drawing up plans to invade the Sun.

              Mock away, liberal pussies, but neutrinos are Weakly-Interacting particles of low-Mass Destruction.

          • No, parent poster was correct (Score:5, Interesting)

            by Flying pig ( 925874 ) on Monday August 27, 2007 @08:52AM (#20370857)
            And in my view insightful rather than funny. Al Gore was a political proponent of the Internet. But the concept of the www (which is just one of the many services running on dat ole Internet)did indeed originate in CERN.

            People often suggest on /. that progress on the Internet is driven by the needs of pornographers. But it would be interesting to know how much progress in networking and databases is actually driven by the (huge) data recording and analysis needs of particle physicists. My own interest in operating systems,networks and databases was started by the need to log large amounts of data very fast from lightning strike simulation experiments.

        • It's almost as if the world's largest particle physics laboratory had something to do with creating it.
          Yeah, they needed somewhere to send those particles, so they made all those tubes!

        • Action at a distance!

    • Re: (Score:3, Interesting)

      by FuzzyDaddy ( 584528 )
      I used to work on the KAMIOKA neutrino detector project (as a lowly undergrad). We looked at Chernkov radiation from scattered electrons, and saw about 1 a day, with huge background (the detector triggered about once a second or more, IIRC.) And certainly not realtime, there was a huge amount of post processing required.

      The Chernkov detectors do give you direction information which this detector does no - but the sensitivity is really impressive.

      One interesting aspect of this result is that it probes

  • Gran Sasso (Score:5, Informative)

    by xPsi ( 851544 ) on Monday August 27, 2007 @07:54AM (#20370411)
    Borexino is really an amazing detector, but has a complex history. The experiment is located at an impressive place called the Gran Sasso National Laboratory [wikipedia.org] (LNGS) in Italy. Technically, it is one of the deepest labs in the world as measured by overburdon -- i.e. it has about a kilometer of rock in every direction to shield cosmic rays-- but is actually located high up in the mountains [wikipedia.org]. Interestingly, it is almost directly under where Mussolini was held prisoner and subsequently rescued [wikipedia.org] by German commandos at Campo Imperatore in 1943. It is also near where the movie Ladyhawke [imdb.com] was filmed. Anyway, back in 2002 there was a chemical accident when some of the liquid scintillator material (highly toxic) got into the local ground water. The leak was an honest mistake and was actually rather minor as chemical spills go, but it caused a public relations debacle which tangled up the lab and, in particular, Borexino, in a long bureaucratic nightmare. I'm happy to see they are now back in the game producing cutting-edge results.

    • Re: (Score:2, Funny)

      by Sunburnt ( 890890 ) *

      Anyway, back in 2002 there was a chemical accident when some of the liquid scintillator material (highly toxic) got into the local ground water.

      Who knew particle physicists were such a kinky bunch?

  • Oops! My bad! (Score:3, Interesting)

    by siglercm ( 6059 ) on Monday August 27, 2007 @08:28AM (#20370633) Journal
    Well, I guess if you're dogmatic about a subject, you should expect to blow your whole leg off someday....

    This is the first story of Roland's that, in my opinion: 1.) Isn't blog whoring (no link back to ZDnet blog, although his home page _is_ pri - midi); and 2.) Is a story of real scientific interest; and 3.) Isn't terribly mis-represented in his summary. So even _I_ won't tag this story.... Isn't that ironic? Don't 'cha think?

    It surprises me how a scientific blogger could get the minor, or sometimes major, technical details of the story he posts about wrong, but at times Roland will. But not this time :^) Good story, Roland!

    • Re:Oops! My bad! (Score:5, Informative)

      by aicrules ( 819392 ) on Monday August 27, 2007 @09:19AM (#20371229)
      Not so fast! Try taking a drink from the firehose on this one. You'll see that while the main link is still there, he DID include a link back to ZDnet that got edited out!

      • Re: (Score:2, Interesting)

        by Anonymous Coward
        You'll see that while the main link is still there, he DID include a link back to ZDnet that got edited out!

        Well then, my compliments to kdawson for showing the way and doing some actual editing.

        • Re:Oops! My bad! (Score:5, Funny)

          by Mr. Underbridge ( 666784 ) on Monday August 27, 2007 @11:47AM (#20373295)

          Well then, my compliments to kdawson for showing the way and doing some actual editing.

          Today's weather forcast calls for airborne swine throughout the country, and a blizzard localized to Hell.

        • Now if this keeps up I wonder if Roland will:
          -Keep submitting stories. (Reputation is good for business)
          -Go away. (No need to waste his time)
          -Send a C&D to slashdot and subsequently sue. (Editing his submission is clearly the creation of a derivative work and needs an additional permission from him to be distributed).

          Time for Taco to add an EULA where you state that your submission might be mercilessly edited.

      • Re: (Score:1)

        by siglercm ( 6059 )
        "Try taking a drink from the firehose on this one."

        Thanks, but my firehose drinking days are over. Last time I tried it, I got plastered against a brick wall. The back of my head hit first. Not fun. ;)

        "You'll see that while the main link is still there, he DID include a link back to ZDnet that got edited out!"

        Then I agree with the AC who replied to you, saying, "my compliments to kdawson for showing the way and doing some actual editing." Roland isn't very reformed, but the /. editor(s) are. I, for one
    • This is the first story of Roland's that, in my opinion: 1.) Isn't blog whoring (no link back to ZDnet blog, although his home page _is_ pri - midi); and 2.) Is a story of real scientific interest; and 3.) Isn't terribly mis-represented in his summary. So even _I_ won't tag this story.... Isn't that ironic? Don't 'cha think?
      --
      Perhaps because the story is not from Roland?

  • Neutrinos massless = timeless, but change state? (Score:3, Insightful)

    by elmartinos ( 228710 ) on Monday August 27, 2007 @09:15AM (#20371173) Homepage
    Last time I have heard something about the Neutrinos, there was an unresolved problem: Neutrinos do not have mass, therefore travel at the speed of light. But since they travel at the speed of light they have no sense of time, and therefore it should not be possible for them to change their state as they are practically frozen in time. This and earlier experiments confirm that despite that they change state. Are there already theories why this is possible?

    • Re:Neutrinos massless = timeless, but change state (Score:3, Informative)

      by Anonymous Coward
      You have correctly stated the problem, and the solution is that they must have some mass. There are several experiments underway to measure what their masses are. They are very tiny, probably sub-eV (for reference, the electron has mass of 511,000 eV. and the proton has mass 938,000,000 eV).

    • Re:Neutrinos massless = timeless, but change state (Score:5, Informative)

      by Angstroman ( 747480 ) on Monday August 27, 2007 @09:44AM (#20371563)
      Indeed, the presumed oscillations imply that the mass of the neutrino is small, but not zero. See, for example http://focus.aps.org/story/v2/st10 [aps.org] for a good discussion. Getting a good experimental measure of the mass of a particle that interacts so weakly with detectors has been a very long running challenge in experimental physics.
    • Neutrinos do not have mass.... therefore it should not be possible for them to change their state

      Actually, that's the whole thing... these experiments which show that neutrino flavor oscillates are evidence that neutrinos DO have mass (and also, don't travel at the speed of light).

      But the fact that a particle travels at the speed of light doesn't necessarily mean it can't change state. It's true, a photon would not be able to measure the passage of time, but stationary observers like us can measure the pas

  • Finally, low calorie neutrinos. (Score:1, Funny)

    by Anonymous Coward
    I love neutrinos, but my doctor said I shouldn't eat them. With new low-energy neutrinos, I can have some without the guilt - - and without my doctor hounding me.

    • Re: (Score:2)

      by zCyl ( 14362 )

      I love neutrinos, but my doctor said I shouldn't eat them.

      It's quite alright. They go right through you.
  • I'm going to wax somewhat sci-fi here and imagine that detection in real-time of neutrinos might have potential application in regards to communication tech.

    In my view I see the ability to detect neutrinos as the first step towards a truly peerless communication system. Imagine that instead of radio waves one were to use neutrino emissions for communication. There would be no (or very little) interference (pass straight through any material) and subsequently the latency of communication from any point on the globe would be decided by the diameter not the circumference of the com point's positions on the earth - meaning that communication delays would be greatly reduced.

    Imagine if any communications device could simply connect directly to any other device on the planet at low-latency with high-signal strength - wouldn't that be neat!

    • Re: (Score:3, Funny)

      by ErikZ ( 55491 ) *

      I know! I was looking at this the other day: http://apod.nasa.gov/apod/ap990623.html [nasa.gov]

      And that just screams "Portable antenna"

      There's no way to grab neutrinos man. The reason there's no interference in neutrino transmission, is because nothing can block it/pick it up.
      • That's the beauty and the bane about neutrinos, isn't it? No interference in transmission, and yet no way to detect them as a result. But here in this article they explicitly say "real-time" detection.

        To me, that is the first step. There must be a way to grab these damn useful phantom particles :)

        • Re: (Score:1, Informative)

          by Anonymous Coward
          Well, problem is... look at what's needed to detect 'em: a HUGE detector mass! (huge amount of target matter).

          I'm afraid that will definitely rule out portable devices... 8-)

        • Re: (Score:1)

          by tqft ( 619476 )
          have thought about this.

          You owe me a copy of next book for this idea

          coupled quantum oscillators - you want the pair to have similar but slightly diff frequencies (sub-eV diff equivalent in energy) and the both need to be very stable - the neutrinos then interact with the frequency difference and show up as a perturbation in one or both of the oscillator systems.

          Hope you prefer replies to mod points.

          • Re: (Score:2)

            by ErikZ ( 55491 ) *
            I have no idea if what you describe works, or is even possible.

            But it would be sweet if it is.

            • Re: (Score:1)

              by tqft ( 619476 )
              The problem is amplifying the perturbation to detectable in the coupled oscillators without destroying the signal or the oscillators - at sub-eV levels it will tough.

              Phase locked quantum oscillators are actually reasonably well studied even though the classical case (and the quantum case) both are tough problems it has been studied - particularly in the area of "Chaos" theory - basically you dump the noise into the environment away from your signal/detector setup

  • The Borexino lie detector almost a mile underground near L'Aquila, Italy
    I'd hate to wake up finding myself there.

  • It's about time. (Score:2, Funny)

    by GigG ( 887839 )
    Thank God, we will finally be able to track the Romulans when they are cloaked.
  • I'm not a physicist but I find such oscillatory behavior fascinating. The first person (as far as I'm aware) to really push geometric relationships of a space as a means to explain its dynamics was Clifford [wikipedia.org]. Einstein went a step further and provided a brillant and comprehensive explanation of the gravity/time/mass/energy relationships as the geometric nature of the space time continuum (correct spelling). Since there are still some really strange anomolies in physics (wave/particle duality for one), its in
  • I already heard this on hate radio last Friday!

    Though it was pronounced "new-try-noes" so maybe that was about a different particle.
  • When I was growing up, there was a theory that at the center of the Earth is a natural fission pile heating the place up. Makes the continents move.

    The experiments of the time, however, did not detect the expected number of neutrinos from that direction. (It was known from human reactors that fission spits neutrinos.)

    Now that we know neutrinos have a tiny mass, and are therefore not moving at the speed of light, and therefore they experience time, and therefore they can and do oscillate ---

    Do these findin

    • Re: (Score:2)

      by habig ( 12787 )
      Do these findings at all bring new life to the Nuke at the Center of the Earth theory?

      The Borexino results do not, but a similar experiment in Japan called Kamland has seen these geo-neutrinos:

      http://www.physorg.com/news5491.html [physorg.com]

      Borexino should also be sensitive to them, but I don't think they've put out a paper on them yet, as the real-time 7Be neutrino detection was the New News.
    • Although this experiment alone may not shed much light on the geo-reactor theory, there are other proposals for neutrino experiments that may. For example, http://arxiv.org/abs/hep-ex/0609041 [arxiv.org] describes a proposal for a deep sea neutrino observatory which could be used to measure thorium and uranium concentrations in the core and mantle. It could also be used to test the geo-reactor theory:

      The second goal is a definitive search for a hypothetical nuclear reactor at Earth's core. This theory (Herndon 1996; Hollenbach and Herndon 2001) has not met wide acceptance by the geological community, who have generally preferred the idea that much of the U/Th rose from the molten, early inner Earth as slag, rather than sank to the core as elemental metal. Yet, many geologists say that there really is no evidence against the hypothesis since the conditions at Earth's formation are little known. Moreover, there are peculiarities in the isotopic content of Earth, and most particularly the observed high ratio of 3He/4He coming out of oceanic volcanic hot spots (such as Hawaii and Iceland), which a natural reactor could explain (3He would come from tritium decay, made abundantly in reactors).

      Slightly off the topic from geo-neutrinos, the same type of experiment could in principle be used to detect "rogue nu

  • Spoon (Score:4, Funny)

    by QuantumPion ( 805098 ) on Monday August 27, 2007 @01:49PM (#20374711)
    In other news, CERN scientists stated that they would have detected 90% more neutrinos, except some jackass was playing an MP3 on the data collecting computer, which happened to be running Vista.

    • Re: (Score:1, Interesting)

      by Anonymous Coward
      Actually Borexino uses Debian Linux for both its data acquisition and data analysis systems.

      No Windows in Vista here @ LNGS! ;-)

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