IceCube search for the 'sterile neutrino' draws a blank

August 8, 2016, University of Wisconsin-Madison
The IceCube Laboratory at the Amundsen-Scott South Pole Station in Antarctica. Credit: Erik Beiser, IceCube/NSF

In an effort to fill in the blanks of the Standard Model of particle physics, science has been conducting a diligent search for a hypothesized particle known as the "sterile neutrino."

Now, with the latest results from an icy particle detector at the South Pole, scientists are almost certain that there is no such particle.

If discovered, the sterile neutrino would have added to the neutrino family portrait and helped explain a number of puzzles that suggest the existence of more than the three known flavors of . Ultimately, such a particle could also help resolve the mystery of the origin of and the matter/antimatter asymmetry in the universe.

Neutrinos are ghostly particles with almost no mass and only rarely interact with matter. Trillions of neutrinos will course through your body in the time it takes to read this sentence. There are three known types of neutrinos: muon, electron and tau. Hints of a possible fourth type of neutrino have come from several experiments. Known as the "sterile neutrino," the hypothesized particle would not interact at all with matter except, possibly, through gravity.

Discovering the sterile neutrino would also throw a wrench into the Standard Model, which allows for only the three known types of neutrino. "If you throw in a fourth neutrino, it changes everything," explains Francis Halzen, a University of Wisconsin-Madison professor of physics and principal investigator for the IceCube Neutrino Observatory, a massive detector embedded deep in the ice beneath the South Pole. "Sterile means it doesn't interact with matter itself, although it can dramatically interfere with the way conventional neutrinos do."

The only way to detect a sterile neutrino is to catch it in the act of transforming into one of the other types. The presence of the sterile neutrino has been hinted at by several experiments, including at the Los Alamos National Laboratory in the 1990s and, more recently, at the Daya Bay nuclear reactor facility near Hong Kong. But definitive evidence of the particle's existence has so far eluded scientists.

Now, in a study published today (Aug. 8, 2016) in the journal Physical Review Letters, IceCube researchers may have largely put to rest the notion of this fourth kind of neutrino. In two independent analyses of data from the massive Antarctic detector—each consisting of a year's worth of data or about 100,000 —the striking feature associated with the sterile neutrino was nowhere to be found, says Halzen.

The analyses were performed using so-called atmospheric neutrinos, neutrinos created when cosmic rays crash into particles in the upper atmosphere of the Earth. The groups conclude that there is 99 percent certainty the eV-mass sterile neutrino hinted at by previous experiments does not exist.

"Like Elvis, people see hints of the sterile neutrino everywhere," says Halzen. "There was this collection of hints, and theorists were convinced it exists."

The groups conducting the analyses scoured the hundreds of thousands of neutrino events that reached the IceCube detector after coursing through the Earth from the sky in the northern hemisphere. Because only neutrinos can travel through the planet unimpeded, the Earth serves as an effective screen, filtering out all other types of particles. IceCube consists of 5,160 light-detecting sensors frozen in crystal clear Antarctic ice more than a mile beneath the South Pole. Neutrinos are detected when they occasionally crash into nuclei, creating a muon and, subsequently, a telltale streak of blue Cherenkov light.

The search conducted by the IceCube teams looked at neutrino events occurring in the 320 GeV to 20 TeV energy range. In this range, Halzen notes, would produce a very distinctive signature.

The appeal of a fourth kind of neutrino is that it would help bridge a gap in theory that predicts that some neutrinos from a beam of one type of neutrino emanating from a given source—be it a nuclear reactor, the sun or the atmosphere—would change from one kind of neutrino to another as they travel to a distant detector. It would also help solve other cosmological puzzles like the mismatch between matter and antimatter in the universe and the origin of dark matter.

"This new result highlights the versatility of the IceCube Neutrino Observatory," according to Olga Botner, a professor of physics and astronomy at Uppsala University in Sweden and the spokesperson for the IceCube Collaboration. "It is not only an instrument for exploration of the violent universe but allows detailed studies of the properties of the neutrinos themselves."

Failing to detect the elusive particle, however, means physics remains in the dark about the origin of the tiny neutrino mass, or why they have mass in the first place, says Halzen.

Explore further: New results confirm standard neutrino theory

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Hyperfuzzy
1.5 / 5 (8) Aug 08, 2016
Blind men describing an elephant limited only by their imagination and one location upon the elephant. Funny or not?
tinitus
Aug 08, 2016
This comment has been removed by a moderator.
DanV
1.6 / 5 (7) Aug 09, 2016
The fact 'sterile neutrinos' are not found is due to the fact gravity is not fundamental. Gravity is emergent! Gravity emerges from a deeper level of physics. In finding evidence for the cause of gravity - and also the cause that matter is dominant over anti-matter -, demands the involvement of the length and time smaller than the Planckscale. Prof. Erik Verlinde from the UvA-NL launched his emergent gravity theory in the institutional area in 2009, while Dan Visser (ing.), Almere, the Netherlands, non-institutional and artpainter, also describes his new cosmology, based on a new formula-set for new dark energy and dark matter, which is also correlating to emergent gravity; in Dan's theory 'duo-bits' recalculate quantum-bits in a rotating holographic universe. No wonder 'sterile neutrinos' are not found. Their interaction with gravity is emergent. Hence another kind of experiments is needed to find them.
Ryan1981
4 / 5 (4) Aug 09, 2016
I was wondering, from the article:

Known as the "sterile neutrino," the hypothesized particle would not interact at all with matter except, possibly, through gravity.


Does this not imply that you won't find the neutrino using:

Neutrinos are detected when they occasionally crash into nuclei, creating a muon and, subsequently, a telltale streak of blue Cherenkov light.

The search conducted by the IceCube teams looked at neutrino events occurring in the 320 GeV to 20 TeV energy range. In this range, Halzen notes, sterile neutrinos would produce a very distinctive signature.


Or am I missing something here?
antialias_physorg
4.5 / 5 (8) Aug 09, 2016
Or am I missing something here?

Here's some detection attepts
https://en.wikipe...attempts

Particularly this part:
More-recent results and analysis have provided some support for the existence of the sterile neutrino. Two separate detectors near a nuclear reactor in France found 3% of anti-neutrinos missing. They suggested the existence of a 4th neutrino with a mass of 0.7 keV

Seems to indicate that the signal is an observed drop in the signal of other neutrino types from the expected value.
tinitus
Aug 09, 2016
This comment has been removed by a moderator.
Hyperfuzzy
1 / 5 (6) Aug 09, 2016
The fact 'sterile neutrinos' are not found is due to the fact gravity is not fundamental. Gravity is emergent! Gravity emerges from a deeper level of physics. In finding evidence for the cause of gravity - and also the cause that matter is dominant over anti-matter -, demands the involvement of the length and time smaller than the Planckscale. Prof. Erik Verlinde from the UvA-NL launched his emergent gravity theory in the institutional area in 2009, while Dan Visser (ing.), Almere, the Netherlands, non-institutional and artpainter, also describes his new cosmology, based on a new formula-set for new dark energy and dark matter, which is also correlating to emergent gravity; in Dan's theory 'duo-bits' recalculate quantum-bits in a rotating holographic universe. No wonder 'sterile neutrinos' are not found. Their interaction with gravity is emergent. Hence another kind of experiments is needed to find them.

Please, shut up. Take a course in mathematical logic and EM theory.
Hyperfuzzy
1 / 5 (6) Aug 09, 2016
A neutrino is an EM wave. No mystery. The mystery is why someone say's it's a mystery. Is this some question for a degree in EM waves that's gotten out of hand?
Ryan1981
1 / 5 (2) Aug 10, 2016
Seems to indicate that the signal is an observed drop in the signal of other neutrino types from the expected value.


Thanks, for clarifying that :D
RNP
3.3 / 5 (7) Aug 10, 2016
@Hyperfuzzy

Neutrinos are NOT EM waves. To claim that they are is a clear indication of a complete lack of knowledge about neutrinos OR EM theory.
Hyperfuzzy
1 / 5 (4) Aug 10, 2016
@Hyperfuzzy

Neutrinos are NOT EM waves. To claim that they are is a clear indication of a complete lack of knowledge about neutrinos OR EM theory.

Prove it. Recall the standard model begins with a gluon. So don't confuse the standard model with EM theory. There are no Neutrinos in EM theory. Only EM waves and charge. Note: charge is never defined as a particle; but, only the center of a spherical field.
Hyperfuzzy
1 / 5 (4) Aug 10, 2016
So first prove SM is acceptable, I say not.
shavera
5 / 5 (5) Aug 10, 2016
Recall the standard model begins with a gluon.

No it doesn't. Again, you and so many others don't even understand the fundamental physics models, so it really is no wonder you think they're full of holes. You absolutely have no capacity to comment on how physics is wrong if you don't even know what physics is saying on a thing.

What the heck is "EM theory" to you, anyway? Because it sure isn't QED, the fundamental description of electromagnetism that predicted experimental outcomes to an accuracy of 11 decimal places. It sure isn't Electroweak unification, the broader, more encompassing theory that describes many phenomena of fundamental particles. Heck, it isn't even capable of explaining black body radiation if it doesn't have a particle nature to it (see "Ultraviolet Catastrophe" for more). So whatever you're calling "EM theory" has little to nothing to do with actual science.
Hyperfuzzy
1 / 5 (4) Aug 10, 2016
Recall the standard model begins with a gluon.

No it doesn't. Again, you and so many others don't even understand the fundamental physics models, so it really is no wonder you think they're full of holes. You absolutely have no capacity to comment on how physics is wrong if you don't even know what physics is saying on a thing.

What the heck is "EM theory" to you, anyway? Because it sure isn't QED, the fundamental description of electromagnetism that predicted experimental outcomes to an accuracy of 11 decimal places. It sure isn't Electroweak unification, the broader, more encompassing theory that describes many phenomena of fundamental particles. Heck, it isn't even capable of explaining black body radiation if it doesn't have a particle nature to it (see "Ultraviolet Catastrophe" for more). So whatever you're calling "EM theory" has little to nothing to do with actual science.

https://drive.goo...5TTBQNjA
Captain Stumpy
5 / 5 (5) Aug 10, 2016
https://drive.goo...5TTBQNjA
@dufus
1- how does a single page non-peer reviewed document on a google drive in any way validate your claims?

2- there is the peer reviewed journal publication for said new modern physics - while you are getting that lined up, please provide the empirical evidence and testable means to validate or falsify your paper linked

3- anyone can link any paper, claim or single page PDF that says anything they want: source is important, especially if you want to make claims about the problems in science as it then becomes about the evidence you have rather than the claim you make (is the evidence valid? is it even real? is it able to be reproduced for verification of your argument? etc)

sorry but that link is PSEUDOSCIENCE (at best you can only claim it's untested)
http://www.auburn...ion.html

Hyperfuzzy
1 / 5 (4) Aug 10, 2016
https://drive.goo...5TTBQNjA


1. not relevent
2. electrical engineering, jeez do your homework, your question infers you know absolutely nothing about Maxwell's Equations
3. OK, so what?


Show me one fact, not some nonsense on how or who published, just know what you are disagreeing is already known physics. I only wish to refute the nonsense of unsupportable claims. Publishing methods offers nothing.
Captain Stumpy
5 / 5 (5) Aug 10, 2016
Show me one fact, not some nonsense on how or who published
@doofus
facts:
1- you linked a single PDF page that has no content (only a title and your name, Doofus), therefore it has absolutely no content that can be considered valid to physics or the topic of science in general

2- the title says "Modern Physics: a correction" but you've yet to provide any empirical math to have peer reviewed, let alone any content from said PDF to demonstrate a failure of physics

3- the last bastion of pseudoscience is to publish (usually self-publish like mundy) because you're not capable of peer review or validation

4- any person can quote any claim they want on a PDF in any format they wish and state it's true or factual, but that doesn't make it either true, factual or science
http://www.auburn...ion.html

need more?
RNP
2.6 / 5 (5) Aug 11, 2016
@Hyperfuzzy
https://drive.google.com/open?id=0B9lix5Gr-zsTQTFFcHJ5TTBQNjA


Your "paper" is nonsense. Just a bunch of unsupported claims padded out by some irrelevant mathematics. It proves nothing other than that the author is delusional.
Hyperfuzzy
1 / 5 (1) Aug 11, 2016
@Hyperfuzzy
https://drive.goo...5TTBQNjA


Your "paper" is nonsense. Just a bunch of unsupported claims padded out by some irrelevant mathematics. It proves nothing other than that the author is delusional.

Argument not to the point. Try science.
Hyperfuzzy
1 / 5 (1) Aug 11, 2016
Show me one fact, not some nonsense on how or who published
@doofus
facts:

need more?

Last I checked I only restated existing science. What's your beef? Be specific. Did I forget to add the nonsense?
shavera
5 / 5 (3) Aug 11, 2016
Okay Fuzz, I finally gave in and read your idiot sheet. It literally, and I mean the dictionary definition of literally, makes absolutely zero sense. It's not even remotely comprehensible.

Read this insane line:
Charge is a spherical field occupying all of space.

NO IT F'ING IS NOT. No wonder you haven't the first bloody clue why no one takes you seriously, you don't even have the basic definitions of words down.

A charge is, by definition, the conserved quantity under a transformation that obeys Noether's theorem. In the sense of EM, that transformation is the Electromagnetic gauge symmetry.

You absolutely cannot go around making up out of thin air whole new definitions for words and then yell at everyone you meet that they're wrong because they aren't using your own home-brewed definitions.

You are an idiot among idiots. A champion of stupidity. And to be brave enough to put your name on this imbicilic document is worth a hearty salute, you complete fool.

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