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Fermilab Confirms Evidence of 4th Flavor Neutrino
eldavojohn writes "We've only had evidence for three kinds of neutrinos so far, but a recent test at Fermilab involving an antineutrino beam has reinforced a Michigan researcher's earlier experiment suggesting a fourth flavor. What's really odd about this is that a prior neutrino test (carried out as part of project MiniBooNE) did not result in indications of such strange oscillations. According to the researcher, 'The simplest explanation involves adding new neutrino-like particles, or sterile neutrinos, which do not have the normal weak interactions.' But this could also be an unknown or misunderstood effect. A Los Alamos National Laboratory scientist added that an explanation of this strange anomaly could result in understanding 'matter asymmetry of the universe, or why the universe is primarily composed of matter, rather than antimatter.' The results are published in the Physical Review Letters."
Will they be ever available in chocolate?
This is sweet!
Sorry, I spilled my Fun Dip packet in there...
Living With a Nerd
4th flavor of neutrino; "I hope it's grape", that's just good comedy right there.
Now, IANAPP (particle physicist), but I thought one of the things discrediting Heim Theory was the prediction of more than 3 neutrinos. What does the presence of a fourth neutrino mean for other predictions made by the current model? Does this mean that Heim's predictions may have more credence?
No, no, no the neutrino flavors follow the same pattern as basic emotions: Happy, sad, approving, disapproving and umami. Umami is a relatively recently discovered emotion. It feels like broth.
Some of my favourite people are from th US; Vonnegut, Chomsky, Bill Hicks.
Neutrinos again? Get back to me when they find something the size of a tennis ball:
http://www.scribd.com/doc/36568510/A-Novel-and-Efficient-Synthesis-of-Cadaverine
If Slashdot were chemistry it would look like this:Cadaverine
I, for one, welcome our new little, neutral overlord.
4th flavor - Racist
Obama's legacy: (N)othing (S)ecure (A)nywhere and (T)error (S)imulation (A)dministration
It feels like broth.
I thought LSD went out of style in the '70s
Faster! Faster! Faster would be better!
Idiocist!
There are two kinds of people: 1) those who start arrays with one and 1) those who start them with zero.
If the universe was primarily made of antimatter instead of matter, would it still be called antimatter?
More Twoson than Cupertino
The Standard Model guys are going to be so irritated when they finally figure out that all these "flavors" are all manifestations of the same thing; what they're doing now is analogous to calling electrons in different shells different particles.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
What has been found is an excess of certain events (namely anti-muon-neutrino to anti-electron-neutrino oscillations), where "excess" is defined relative to the current best-established model. So what this experiment (if correct) shows, is that the current model is not good enough.
From the PRL paper:
The source of the excess remains unexplained, although several hypotheses have been put forward
One of those hypotheses is additional neutrino flavours, but this finding is not evidence for that.
fuck everything, we're doing five neutrinos...
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
sorry
The actual problem with Heim theory is that it predicted the existence of a neutral equivalent to the electron (per the theory, it should be commonly observed in particle interactions). The fact that such a particle has never been seen is considered a big strike against Heim.
The evidence for an asymmetry between matter and anti-matter has been growing for some time now (cosmological observations, recent muon experiments and now this). It used to be said that an antiparticle was a particle travelling backwards in time. So how does these findings affect our understanding of the asymmetry of time?
You will not drink with us, but you would taste our steel? - Walter Matthau, The Pirates
The scientific article does a reasonable job of making it clear that this result has a 0.5% probability of being produced entirely by background assuming that the systematics of the result are not playing evil games with you. While this result is interesting and it may, strictly speaking, "confirm evidence of 4th neutrino flavor" it only does so by being consistent with both a background fluctuation and some theories developed to describe a discrepancy similar to that seen in the data. It most certainly does not eliminate the standard model nor does it pick out any particular theory.
The MiniBooNE experiment at Fermilab reports results from a search for e oscillations, using a data sample corresponding to 5.66×1020 protons on target. An excess of 20.9±14.0 events is observed in the energy range 475EQE1250MeV, which, when constrained by the observed events, has a probability for consistency with the background-only hypothesis of 0.5%. On the other hand, fitting for e oscillations, the best-fit point has a 2 probability of 8.7%. The data are consistent with e oscillations in the 0.1 to 1.0eV2 m2 range and with the evidence for antineutrino oscillations from the Liquid Scintillator Neutrino Detector at Los Alamos National Laboratory. Yeah, well, no fine...
Excuse me, but please get off my Pennisetum Clandestinum, eh!
"Sterile neutrinos could also possibly help explain the matter asymmetry of the universe,
Isn't it a bit over confidence when assuming and hoping that a neutrino that only interacts via gravity can explain, or was responsible for Baryonic Asymmetry?. None of the *possible* explanations (CP-violation, more matter somewhere than antimatter, antimatter pushed somewhere else etc) I have read anywhere hinted that a hypothetical neutrino, and especially a sterile one, could explain asymmetry. So I am going to take that as a one scientist opinion and hope.
"Physicists at the lab now believe that antimatter particles behave pretty much in the same way as their regular matter counterparts do."
Glad they recognized the discrimination, neutrino rights are a big issue these days.
He who knows best knows how little he knows. - Thomas Jefferson
http://cheezburger.com/View/4126230016
Let us fantasize about how a matter-symmetric universe would evolve.
I bet it would be very morphogenetically boring: no structure, no stars, no life. If it was symmetric, it would not have created us to comment on it.
It is asymmetric because we are here, and conversely.
I think I think, therefore I think I am.
I don't understand why this should be considered strange. Scientists acknowledge that they have only gathered about 1% of the total amount of information available in the universe. Thus the study of the universe is in its infancy and thus new data that contradicts known data shouldn't be considered to be a "strange anomaly". Since when as knowledge gathered from the first 1% of the data in any large study been considered conclusive? Doesn't that missing 99% of the data say any conclusions drawn from the first 1% say that those conclusions should be considered as nothing more than preliminary suppositions?
"while democracy seeks equality in liberty, socialism seeks equality in restraint and servitude." de Tocqueville
This one is obvious! There are only four elements; Earth, wind, fire, and water, so there are only four neutrino. That is it. There are no anti anything. From one side your anti and from the other your not.
"The laws of science be a harsh mistress." --Bender
Cosmic Gall, by John Updike
NEUTRINOS, they are very small.
They have no charge and have no mass
And do not interact at all.
The earth is just a silly ball
To them, through which they simply pass,
Like dustmaids down a drafty hall
Or photons through a sheet of glass.
They snub the most exquisite gas,
Ignore the most substantial wall,
Cold shoulder steel and sounding brass,
Insult the stallion in his stall,
And scorning barriers of class,
Infiltrate you and me! Like tall
and painless guillotines, they fall
Down through our heads into the grass.
At night, they enter at Nepal
and pierce the lover and his lass
From underneath the bed-you call
It wonderful; I call it crass.
So what is the problem with this reasoning? And could the sterile neutrino from this story be actually such a right-handed neutrino?
First: it cannot be dark matter because neutrinos are too light and hence move too fast. The result is that the WMAP cosmic microwave background would be blurred out far more than it is so we know that, whatever the dark matter is, it is slow moving and so not a light neutrino.
Second: MiniBoone has interesting results but have not BY ANY STRETCH of the imagination confirmed the existence of a 4th gen of neutrinos. Their signal is only 0.6% incompatible with background. To claim evidence the standard in the field is 3 std. dev. (or 0.27%) and to claim a discovery it is 5 sigma (0.000057%). Effects like this go away all the time and can easily be caused by errors. This is not a guarantee that theirs will but, to make claims like this you need solid, statistical evidence and they do not yet have that.
Third: we already know that right handed neutrinos exist because the neutrino has a non-zero mass. Any mass term in the Lagrangian mixes left and right helicity states. Effectively what this means is that if you have a left handed neutrino but chase after it faster than it is moving (which you can do because it has a mass) it will be a right handed neutrino to you. So, if there is anything interesting happening here, it is not a "normal" right handed neutrino.
And it produces 31 different flavors of neutrinos. Physicists also receive one free particle of anti-matter on their birthdays.
According to Professor Hubert G. Farnsworth, the neutrino tastes like GrapeAid. The next question to answer is..... WILL IT BLEND??
Knowing Google's lust for data collection, the Soviet Union is still alive and well inside the psyche of Sergey Brin....
Neutrino walks into a bar. Bartender says "We don't serve neutrino's here!"
Neutrino says, "Just passing through."
http://stephan.sugarmotor.org
This is why I love particle physics. I am a scientists by training, but not a physicist, and while I have the sense that you two are not speaking gibberish, I can't be sure :) Or to put it another way, to paraphrase Arthur C. Clarke, "Any sufficiently advanced physics is indistinguishable from gibberish."
I think he means that it feels warm, wet, and gets sticky as it dries. (Of course, many other things beside broth do this too, but we were discussing broth here.)
That's like, your opinion, man.
I am a particle physicist working at CERN. In September I attended a seminar presenting recent results from the HARP-CDP group. They performed an independent analysis of data recorded by the HARP detector at CERN. There was some interesting discussion on MiniBooNE's results afterwards.
Summary: MiniBooNE's estimate of their signal significance is questionable. Firstly, the error bars on the data are huge; what MiniBooNE reports could be a statistical fluke. More data is needed. It's too early to announce anything. Secondly, questions have been raised about MiniBooNE's background estimation. They factored-in hadroproduction data from the HARP Collaboration. The HARP-CDP group found significant discrepancies in other data obtained by the HARP Collaboration. HARP-CDP's and HARP Collaboration's results do not agree. HARP-CDP don't have access to the same hadroproduction data supplied to MiniBooNE, but clearly there is sufficient reason to question MiniBooNE's knowledge of their backgrounds. Hence, MiniBooNE's knowledge of their signal background could be wrong.
Symmetry in this case refers to this: If you take a particle or a diagram describing a particle interaction and "flip something", you get something new that is still valid. Take a proton and flip the charge and you get an anti-proton for instance. Because of this symmetry, matter and anti-matter behave in exactly the same way, or so we belive. your particle and your the flipped version decay in the same way for instance.
What physicicst discovered over the last century was that it's not enough to flip the charge to make this valid in all cases. You have to flip charge, direction of time and flip something called "parity". Flipping the direction of time means simply to draw a feynman diagram of a particle collision or interaction on an overhead foil so that time runs from left to right and then turn it backwards. That's the mirror-image of the interaction.
But as I said you have to flip both time, parity and charge to get a valid diagram, and that's the origin of the term "an antiparticle is a particle travelling backwards in time"