Chemist Travels World to Study Mysterious Properties of Neutrinos

August 19, 2008

In the quest to better understand one of nature's most "ghostly" elementary particles — the neutrino — scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory are spreading their expertise from the mines of Canada to the mountains of China. Richard L. Hahn, a senior chemist at Brookhaven Lab, will discuss some of the neutrino's mysterious properties and two new neutrino research projects at the 236th National Meeting of the American Chemical Society on Tuesday, August 19, 2008.

Neutrinos are uncharged elementary particles created by nuclear reactions in the sun, by cosmic rays in our atmosphere, and in nuclear reactors and accelerators on Earth. The properties of neutrinos continue to fascinate scientists as they analyze the role of neutrinos in the universe.

Brookhaven's history of solar neutrino research dates to the early 1970s, when scientist Ray Davis' pioneering work in a South Dakota gold mine sent the neutrino world into an uproar by documenting that fewer electron neutrinos (the type produced by the sun) were detected than should have been based on theory. Davis (along with Masatoshi Koshiba of Japan and Riccardo Giacconi of the U.S.) was awarded a Nobel Prize in Physics for this work in 2002.

That same year, scientists at the Sudbury Neutrino Observatory (SNO) in Ontario, including Hahn and members of his Brookhaven group, solved Davis' "solar neutrino problem" by determining that neutrinos "oscillate," or switch, between three different types as they travel from the sun to Earth. Thus, Davis' observed electron neutrinos were only a fraction of the total number reaching earth. The rest had changed into muon or tau neutrinos that were not detected in Davis' original experiments.

Now, researchers at Brookhaven and across the world are turning their attention to two new efforts in the neutrino field: the experiment at the Daya Bay Nuclear Power Plant in China, and the SNO upgrade, called SNO+. In his talk, Hahn will provide the details of these large-scale experiments.

"In these experiments, we are asking a very fundamental question: How can we better understand the detailed properties of neutrinos?" Hahn said.

Researchers have clearly characterized two of the neutrino oscillations between different flavors, but they still do not know the details of the third oscillation. The goal of the Daya Bay experiment, a collaboration among researchers in the United States, China, Hong Kong, Taiwan, Russia, and the Czech Republic, is to measure an essential parameter of this third oscillation known as the mixing angle θ13 (pronounced "theta-one-three").

"In order to understand neutrino mixing and oscillations, we must know the value of the unknown mixing angle," Hahn said. "All we know so far is that it is small."

To determine this angle, researchers will use eight 80-ton detectors to look at antineutrinos, the antiparticles of neutrinos, which are produced in nuclear reactors. Each detector contains a metal organic liquid mixture in the center that is surrounded by organic liquid without any metal, both of which Hahn and his group at Brookhaven have helped to develop. When neutrinos pass through the metal organic liquid mixture, flashes of light are produced. By placing detectors at different distances from the reactors, Hahn and colleagues will be able to map antineutrino oscillations from one flavor to another.

Hahn and his group are developing another metal organic liquid mixture to detect neutrinos in the SNO+ experiment. This experiment will use the same general set-up from the completed SNO experiment — a large, round, acrylic vessel the size of a 10-story building (described as the world's largest round-bottomed flask) placed 6,800 feet underground in the International Nickel Company's Creighton Mine. SNO+ researchers will replace the heavy water used for SNO with metal organic liquid mixture.

The researchers working on SNO+ will be studying double-beta decay, a rarely seen radioactive decay mode — in which two neutrons are changed into protons, emitting two electrons and (most often) two neutrinos. A main goal of the experiment will be to search for double beta decay in which no neutrinos are emitted — a mode that has never been seen before

"This would show that the neutrino is its own antiparticle," Hahn said. "Currently, some evidence suggests that neutrinos are different from antineutrinos, while certain theories predict that they are actually the same particle. It is important to understand whether those theories are true or not."

"There should have been equal amounts of matter and anti-matter present at the Big Bang, the beginning of the universe," Hahn said. "Today, however, matter dominates our Earth — explaining why we don't annihilate each other when we shake hands. If the neutrino turns out to be its own antiparticle, this might help us to understand more about this imbalance.

"This experiment asks key questions about how our corner of the universe exists today as it does — with matter but no anti-matter."

Source: Brookhaven National Laboratory


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  • Question - Aug 19, 2008
    • Rank: 3 / 5 (2)
    Could neutrinos be neutral radiation in the high frequency range of gamma ray?
    A book called An Alternative to the Standard Model of Physics makes that claim.
    If neutrinos were actually neutral radiation most all the mysterious aspects of the neutrino would disappear. That would explain the seemingly infinite energies of a neutrino. This is a problem one never hears discussed, how can a neutrino that travels at the velocity of light, contain a multitude of different energy levels?
  • Alizee - Aug 19, 2008
    • Rank: 4 / 5 (1)
    The question is, what the "neutral radiation" should be. The neutrinos have charge, they can move by arbitrary speed, they're forming three generations and they're way lighter, then the photons of gamma radiation (E=hn). If we realize the vacuum as a nested foam by AWT

    http://superstrun...Foam.gif

    then the neutrinos are formed by undulations of lightweight portion of that foam. The photons are involving more then single level of that foam.

    http://superstrun...gens.gif
  • Alizee - Aug 19, 2008
    • Rank: 5 / 5 (2)
    ..how can a neutrino that travels at the velocity of light, contain a multitude of different energy levels?..
    By my understanding, neutrinos can propagate by arbitrary subluminal speed like other particles. Maybe you should change your textbook - it generates problems artificially.
  • yyz - Aug 20, 2008
    • Rank: 5 / 5 (1)
    If neutrinos possess extremely small masses (compared to the electron) how can they travel at the speed of light? I thought all massive particles increase greatly in mass & require energies approaching infinity as they approach lightspeed, but cannot ever travel at the speed of light, at least in the context of General Relativity. How could massless gamma-ray photons be related in any way to extremely lightweight neutrinos?
  • Question - Aug 20, 2008
    • Rank: 3 / 5 (2)
    Good question yyz, how can neutrinos travel at the speed of light if they do have mass? A supernova in 1987 confirms that they do indeed travel at the speed of light. That problem is eliminated if neutrinos are neutral radiation in the high frequency range of gamma rays. It is all explained in the book mentioned above in the first posting.

    It is really simple, as simple as the binary system used in our computers.
  • Alizee - Aug 21, 2008
    • Rank: not rated yet
    ..A supernova in 1987 confirms that they do indeed travel at the speed of light...
    By astronomical observations the 99.99% percent of light speed is undistinguishable from 100% light speed. While the former is still allowed for neutrinos as a classical particles, it can explain both your supernovae observation, both the continuous spectrum of energy levels WITHOUT introduction of some new concepts, thus passing Occam's razor criterion.
  • Question - Aug 21, 2008
    • Rank: not rated yet
    Thanks for making that point about Occam's razor criterion. The present explanation considering neutrinos as particles needs a few more assumptions than just simply considering neutrinos as neutral radiation. For example; assuming neutrinos have a variety of speeds below the speed of light to accommodate the spectrum of energy levels and assuming neutrinos oscillates from one species to another. Both of these are unnecessary if one considers neutrinos as radiation. Also no antiparticle to look for because neutral radiation would be it own antiparticle. It would greatly simplify our understanding of the neutrino (neutral radiation).
  • Alizee - Aug 21, 2008
    • Rank: not rated yet
    assuming neutrinos have a variety of speeds below the speed of light to accommodate the spectrum of energy levels and assuming neutrinos oscillates from one species to another. Both of these are unnecessary if one considers neutrinos as radiation
    Nope, these properties are the features of neutrino particle models, not the assumption. How do you want to explain, only one third of solar neutrino flux remains detectable on Earth? Just the neutrino oscillations can explain this. Just the particle model can explain the continuous energy levels of neutrino flux, etc.
    ..no antiparticle to look for because neutral radiation would be it own antiparticle..
    How do you explain the fact, antineutrino has the opposite lepton charge to neutrino, after then?

    After all, did you ever think, what the "neutral radiation" should be? Does it fullfill Maxwell equations? Can you draw it? Does some analogy of such concept ever exist?
  • Question - Aug 21, 2008
    • Rank: not rated yet
    Nope, these properties are the features of neutrino particle models, not the assumption. How do you want to explain, only one third of solar neutrino flux remains detectable on Earth? Just the neutrino oscillations can explain this. Just the particle model can explain the continuous energy levels of neutrino flux, etc.
    Nope, these properties are the features of neutrino particle models, not the assumption. How do you want to explain, only one third of solar neutrino flux remains detectable on Earth? Just the neutrino oscillations can explain this. Just the particle model can explain the continuous energy levels of neutrino flux, etc.
    ---Question
    I have never read any test proving that neutrinos have this unusual ability to transmit different amounts of energy because they have the special features you claim they have. Exactly what are these features? It is actually very simple if neutrinos are really neutral radiation. If one shines a light through a glass sphere some is absorbed by the glass sphere. It is exactly the same with neutral neutrino radiation, about a third of it is absorbed by the sun itself and never makes it to the earth.

    How do you explain the fact, antineutrino has the opposite lepton charge to neutrino, after then?
    -----Question
    If neutrinos are really neutral radiation lepton charge become irrelevant just like the charge of the radiation from an electron or proton.

    After all, did you ever think, what the "neutral radiation" should be? Does it fullfill Maxwell equations? Can you draw it? Does some analogy of such concept ever exist?
    -- - - Question
    It would not directly fulfill Maxwell equations because it is neutral. It cannot be controlled. And well yes, I can draw it. If light is actually a wave of particles and not photons or waves in the classical sense, it would look like this: > < > < > etc.. Each 1/2 wave of light is a separate particle with an opposite spin. That is where the alternating electromagnetic characteristic of light come from. Neutral neutrino radiation would look like this: >< >< >< >< etc.. The two alternating spin particles join as one neutral particle. The neutral field surrounding the neutron is actually what is radiated away as a nucleus drops to a lower energy level or when a neutron decays.

    I am new at this and may not have this quote thing done right, sorry.
  • Question - Aug 21, 2008
    • Rank: not rated yet
    The light waves did not copy correctly and should look like this: > < > < > etc..
    The neutral radiation should look like this:
    >< >< >< >< etc..

    I hope this post correctly.

    I notice it is still not posting as typed, there should be spaces between each particle for light waves and there should be space between every other particle for neutral neutrino radiation.

  • Question - Aug 22, 2008
    • Rank: not rated yet
    Okay let me give this a third try.

    Electromagnetic radiation (emr) is a wave that alternates an electromagnetic field. It could be represented like this: (hyphen for spacing only)
    ----- etc..
    Each is a single wave of radiation equal to one Planck's constant.
    Neutral neutrino radiation (nnr) can be represented like this:
    ----------------------- etc..
    Each is a single wave of neutral neutrino radiation equal to one Planck's constant.
    The only difference between the two is that neutral radiation does not have an alternating electromagnetic field. The two opposite parts of the wave are combined into a single neutral unit.
    Now the important part is that BOTH emr and nnr transmit and identical amount of energy and momentum.

    Now we can go back and deal with your missing neutrinos from the sun, they are only missing because they are absorbed before they ever exit the sun. Neutrinos are not nearly as penetrating as current theory maintains.
    The proof is in the missing neutrinos passing through the earth. They do not oscillate into different species of neutrinos they are absorbed by the earth.

    All of this information is available in the book titled; "An Alternative to the Standard Model of Physics".
  • Question - Aug 22, 2008
    • Rank: not rated yet
    I am sorry but for some reason it is still not posting correctly. Let me try one more time here:
    emr: ---------- etc.
    nnr: ------------------------- etc.

    NO LUCK SORRY
  • earls - Aug 22, 2008
    • Rank: not rated yet
    Draw a picture in MS Paint (Windows Key R, type "mspaint", enter), save as a jpg, and upload it on www.imageshack.us (uncheck yahoo jobs) then post the link on here.
  • earls - Aug 22, 2008
    • Rank: not rated yet
    You suck physorg.

    1st, stop removing special characters. I assume this is from HTML parsing/removal.

    2nd, tone down or get rid of that nonsensical three minutes between posts.

    3rd, "Got a Question? Ask." is redundant and useless considering you need another account.

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