Missing Solar Neutrinos - First Results

[yevaud]

<b>First Results From The Sudbury Neutrino Observatory Explain The Missing Solar Neutrinos And Reveal New Neutrino Properties</b><br /><br /><i>June 18, 2001 -- Physicists from Canada, the U.K. and the U.S. are today announcing that their first results provide a solution to a 30-year old mystery * the puzzle of the missing solar neutrinos. The Sudbury Neutrino Observatory (SNO) finds that the solution lies not with the Sun, but with the neutrinos, which change as they travel from the core of the Sun to the Earth. Neutrinos are elementary particles of matter with no electric charge and very little mass. <br /><br />There are three types: the electron-neutrino, the muon-neutrino and the tau-neutrino. Electron-neutrinos, which are associated with the familiar electron, are emitted in vast numbers by the nuclear reactions that fuel the Sun. Since the early 1970s, several experiments have detected neutrinos arriving on Earth, but they have found only a fraction of the number expected from detailed theories of energy production in the Sun. This meant there was something wrong with either the theories of the Sun, or the understanding of neutrinos.<br /><br />"We now have high confidence that the discrepancy is not caused by problems with the models of the Sun but by changes in the neutrinos themselves as they travel from the core of the Sun to the earth," says Dr. Art McDonald, SNO Project Director and Professor of Physics at Queen's University in Kingston, Ontario. "Earlier measurements had been unable to provide definitive results showing that this transformation from solar electron neutrinos to other types occurs. The new results from SNO, combined with previous work, now reveal this transformation clearly, and show that the total number of electron neutrinos produced in the Sun are just as predicted by detailed solar models."</i><br /><br />Full Story <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[drwayne]

Interesting.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[vogon13]

Just curious, would Heisenbergs Uncertainity Principle allow neutrinos a non-zero mass and yet still permit propagation at speeds just short of C (and in fact, uncertainly just short of C)?<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[mikeemmert]

There's some kind of New Physics going on here, that's for sure.<br /><br />If Heisenburg's Uncertainty Principle applied to neutrinos, then should it not also apply to photons? This is not observed.<br /><br />Unfortuneately, there is a lot about neutrinos which is not observed...

 

[vogon13]

Can't recall specifically, but something about CPT violations is specific to neutrinos and not photons.<br /><br />Might all be related . . . .<br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[yevaud]

Well, of course, as Neutrinos have been found to possess mass, they have certain restrictions on their behavior; but one "restriction," in the opposite sense, is that to change their type as with this, they <i>must</i> possess mass.<br /><br />Intriguing to say the least. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[michaelmozina]

<blockquote><font class="small">In reply to:</font><hr /><p>The SNO detector, which is located 2,000 meters below ground in Inco's Creighton nickel mine near Sudbury, Ontario, uses 1,000 tonnes of heavy water to intercept about <b>ten</b> neutrinos per day. The results being reported today are the first in a series of sensitive measurements that SNO is performing. From this initial phase, the SNO scientists report on an accurate and specific measurement of the number of solar electron neutrinos reaching their detector, by studying a reaction unique to heavy water where a neutron is changed into a proton. They combined these first SNO results with measurements by the SuperKamiokande detector in Japan of the scattering of solar neutrinos from electrons in ordinary water (offering a <b>small sensitivity to other neutrino types</b>), to provide the direct evidence that neutrinos oscillate.<p><hr /></p></p></blockquote><br /><br />Emphasis mine.<br /><br />It seems to me if someone wished to play devils advocate on this issue, it wouldn't be very difficult. After all, they only recieve a total of 10 out of countless neutrinos that pass right through their equipment undetected every single day. It seems like a very small sampling frankly. I also fail to understand how you can have only a very "small" sensitivity to the other types of neutrinos and really know that anything is changing flavors. If they documented the fact that they transmitted 10 neutrinos of one particular flavor from one location to another, and noticed that two of them changed in mid flight, I might be more convinced. As it is, it seems like a lot of these ideas are based on a miniscule sampling, and the insensitivity to other flavors of neutrinos makes the argument a lot less convincing from my perspective. It is "interesting", but when they use terms like "definitive results" based on ten hits a day, I can't help but think the work is being "hyped" quite a bit. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[drwayne]

I'm sure there is a design of experiments case study here.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[drwayne]

I have a cousin who spent a number of years in a mine in Russia (ended up with a Russian wife) doing neutrino measurements - I haven't talked to him in many years, maybe I need to give him a call.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[nexium]

I hope they are correct, as an alternate explanation is the core of the sun went to half power about 60 million years ago. The nuetrinos arrive in 8 minutes, but other energy takes about 60 million years to reach the photosphere from the core. New ice age if the photosphere cools a thousand degrees k. Neil

 

[zenpunk]

Why is assumed that the neutrinos are changing flavor when there isn't even a proposed mechanism for them to do so? Isn't it equally likely that the sun is producing all three types directly?

 

[CalliArcale]

My brother explained it to me once. (He did his doctoral thesis on muons, and spent several years working at the MINOS neutrino detector in Soudan, Minnesota.) It made sense at the time, but it's way far away from the stuff I've studied, so I couldn't hope to repeat the explanation correctly. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[drwayne]

Tangentially related:<br /><br />The muon was discovered when searching for the Yukawa exchange particle. When it was described, and it properties were not what was expected of the Yukawa particle, I.I. Rabi came up with one of the best lines in physics - "Who ordered that?"<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[mlorrey]

"Why is assumed that the neutrinos are changing flavor when there isn't even a proposed mechanism for them to do so? Isn't it equally likely that the sun is producing all three types directly?"<br /><br />No, because hydrogen fusion only produces one type, electron-neutrinos, there isn't enough mass lost between hydrogen and helium fusion reactions to equal muon or taus... Muon and tau neutrinos are produced by other reactions (other than flipping from electron-neutrinos).<br /><br />Now, what this does mean is that, while there is no ice age directly imminent (Nexium, could you find a reference for that 60 million year time to heat transmission please? My recollection is its something like 5,000-6,000 years), we also have a useful instrument now for predicting future solar emissions, AND, if we can develop some means of determining historic neutrino levels based on isotope levels in various deposits, develop a much more accurate long term proxy for solar activity.

 

[michaelmozina]

<blockquote><font class="small">In reply to:</font><hr /><p>No, because hydrogen fusion only produces one type, electron-neutrinos, there isn't enough mass lost between hydrogen and helium fusion reactions to equal muon or taus... Muon and tau neutrinos are produced by other reactions (other than flipping from electron-neutrinos).<p><hr /></p></p></blockquote><br /><br />Then again, we do not know for sure that hydrogen fusion is the only source of neutrino emissions from the sun. Hydrogen fusion may in fact play a *role* in neutrino emissions, but it need not be the *only* mechanism to explain the presense of neutrinos. There is also evidence of neutron capture signatures in the coronal loops, and positron annihilation signatures at the footprints of the coronal loops. I personally think it's *way* early to be "assuming" that the sun emits only a single "flavor" of neutrino. <br /><br />http://svs.gsfc.nasa.gov/vis/a000000/a002700/a002750/<br />http://arxiv.org/abs/astro-ph/0512633<br /><br />IMO, this is a clear case of trying to make the evidence "fit" the predictions rather than studying the phenomenon in any depth. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[michaelmozina]

<blockquote><font class="small">In reply to:</font><hr /><p>Why is assumed that the neutrinos are changing flavor when there isn't even a proposed mechanism for them to do so? Isn't it equally likely that the sun is producing all three types directly?<p><hr /></p></p></blockquote><br /><br />Yes! It is equally likely that the sun kicks out a variety of different flavors of neutrinos. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>I personally think it's *way* early to be "assuming" that the sun emits only a single "flavor" of neutrino. <p><hr /></p></p></blockquote><br /><br />As I understand it (and particle physics is not my strong suit), they don't assume that the Sun emits only one flavor. Not anymore, anyway. That's part of the point -- if neutrinos regularly flip between three flavors, it doesn't matter which flavor is being emitted more; given enough distance, you'll detect all three flavors in roughly equal proportions no matter what is emitted. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[doubletruncation]

Wasn't this also detected by super kamiokande as well (the oscillations)? If I remember right, in that case they were looking for muon neutrinos produced by cosmic rays hitting the earth's atmosphere. ... Ok here is, for example, a source for this (http://www.phys.hawaii.edu/~jgl/nuosc_story.html).<br /><br />So they say that they were expecting twice as many atmospheric muon neutrinos as electron neutrinos but the observed ratio was more like 1:1. And if I remember right, they were then able to detect that the ratio was lower for neutrinos coming from below the earth than for neutrinos coming from directly overhead, and that is what you'd expect if the muon neutrinos oscillated into other flavors in the longer path length through the earth. I don't think their experiment relied on knowing how neutrinos are produced in the sun (I imagine they would just ignore any event coming from the direction of the Sun).<br /><br />Anyway, there is a massive body of research (theory and experiment) on this subject:<br />http://xxx.lanl.gov/find/astro-ph/1/abs:+AND+neutrino+oscillation/0/1/0/all/0/1 <div class="Discussion_UserSignature"> </div>

 

[doubletruncation]

<i>Hydrogen fusion may in fact play a *role* in neutrino emissions, but it need not be the *only* mechanism to explain the presense of neutrinos. There is also evidence of neutron capture signatures in the coronal loops, and positron annihilation signatures at the footprints of the coronal loops</i><br /><br />But do these other processes make significant contributions to the total neutrino flux from the sun? I mean, presumably you can put an upper limit on the extent of these processes, does it compare at all with the electron neutrino flux from the core?<br /> <div class="Discussion_UserSignature"> </div>

 

[serak_the_preparer]

Something weird is going on - but as yet no one's quite sure what:<br /><br />MiniBooNE Findings Clarify the Behavior of Neutrinos by Janet Rettig Emanuel (Yale University)<br /><br /><b>New Haven, Conn.</b><i> — The initial data from the 10-year long “MiniBooNE” experiment at the Department of Energy's Fermilab significantly clarifies the overall picture of how the fundamental particles, neutrinos, behave. <br /><br />The project was designed to confirm or refute surprising observations from the Department of Energy's Los Alamos National Laboratory’s Liquid Scintillator Neutrino Detector (LSND) experiments in the 1990’s that were explained simply by the ability of neutrinos to transform from one type into another and back again, a process called neutrino oscillation. This research showed conclusively that there is more to the story....<br /><br />The MiniBooNE experiment mimicked the earlier Liquid Scintillator Neutrino Detector (LSND) experiment by looking for signs of muon neutrinos oscillating into electron neutrinos in the region indicated by the LSND observations. The team expected that the experiment would produce a distinct background and oscillation “signature.”<br /><br />The results found no appearance of electron neutrinos as predicted by a simple two-neutrino oscillation scenario ruling out the simple LSND oscillation interpretation....<br /><br />Currently, three types or “flavors” of neutrinos are known to exist: electron neutrinos, muon neutrinos and tau neutrinos. In the last 10 years, several experiments have shown that neutrinos can oscillate from one flavor to another and back. The observations made by the LSND collaboration also suggested the presence of neutrino oscillations, but in a neutrino mass region vastly different from other experiments. <br /><br />“You can’t see them, hear them, or touch them, but neutrinos are everywhere. They pass right by us and right through us. They</i>

 

[michaelmozina]

That is a very interesting article. The fact they did not see any type of oscillation from a muon neutrino into electron neutrino is rather telling IMO. Maybe neutrinos oscillate, maybe they don't. The lepton conservation laws may not be being violated after all. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[yevaud]

IIRC, it has been damned near a year since you've been here, Michael. Welcome back. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[michaelmozina]

Thanks. It's good to be back. <img src="/images/icons/smile.gif" /><br /><br /> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[yevaud]

Well, call it a Kudo, but as a proponent of the Electric Universe, you appear to be one of the few who can debate it with good science. That would make you an exception to the rule, as stated to Nevyn. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[michaelmozina]

I plan to start a thread devoted to explaining the excess energy of the corona, and the sun's coronal loops from the perspective of plasma cosmology. <br /><br />In that thread I will post some links to our last paper about fusion in the solar atmosphere that was published late last year in the Journal Of Fusion energy. <br /><br />I think you'll be very pleased with the science. <img src="/images/icons/smile.gif" /><br /><br />As soon as things slow down at work, I'll start a new thread. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>