Solar physicists unlock easier way to observe peculiar particles that reveal the inner workings of the sun

November 9, 2016 by Taylor Kubota
Workers maintain the Super-Kamiokande neutrino detector in Hida, Japan. Credit: Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo

In 2009, applied physicist Peter Sturrock was visiting the National Solar Observatory in Tucson, Arizona, when the deputy director of the observatory told him he should read a controversial article about radioactive decay. Although the subject was outside Sturrock's field, it inspired a thought so intriguing that the next day he phoned the author of the study, Purdue University physicist Ephraim Fischbach, to suggest a collaboration.

Fischbach replied, "We were about to phone you."

More than seven years later, that collaboration could result in an inexpensive tabletop device to detect elusive more efficiently and inexpensively than is currently possible, and could simplify scientists' ability to study the inner workings of the sun. The work was published in the Nov. 7 issue of Solar Physics.

"If we're correct, it means that neutrinos are far easier to detect than people have thought," said Sturrock, professor emeritus of applied physics. "Everyone thought that it would be necessary to have huge experiments, with thousands of tons of water or other material, that may involve huge consortia and huge expense, and you might get a few thousand counts a year. But we may get similar or even better data from an experiment involving only micrograms of radioactive material."

Why, how we study neutrinos

For twenty years, Sturrock and his colleague Jeff Scargle, astrophysicist and data scientist at NASA Ames Research Center, have studied neutrinos, subatomic particles with no electric charge and nearly zero mass, which can be used to learn about the inside of the sun.

Nuclear reactions in the sun's core produce neutrinos. A unique feature of neutrinos is that they rarely interact with other particles and so can escape the sun easily, bringing us information about the deep solar interior. Studying neutrinos is thought to be the best way to obtain direct information about the center of the sun, which is otherwise largely a mystery. Neutrinos can also give us information about supernovas, the creation of the universe and much more.

On Earth, an area the size of a fingernail has 65 billion neutrinos pass through it each second. But only one or two in an entire lifetime will actually stop in our bodies. Studying neutrinos involves massive equipment and expenses to trap enough of the elusive particles for investigation.

At present, the gold standard for neutrino detection is Japan's Super-Kamiokande, a magnificent $100 million observatory. In use since 1996, Super-Kamiokande lies 1,000 meters below ground. It consists of a tank filled with 50,000 tons of ultra-pure water, surrounded by about 13,000 photo-multiplier tubes. If a neutrino enters the water and interacts with electrons or nuclei there, it results in a charged particle that moves faster than the speed of light in water. This leads to an optical shock wave, a cone of light called Cherenkov radiation. This light is projected onto the wall of the tank and recorded by the photomultiplier tubes.

Past challenges in detection

The 2002 Nobel Prize in Physics was awarded to Masatoshi Koshiba of Super-Kamiokande and Raymond Davis Jr. of Homestake Neutrino Observatory for the development of neutrino detectors and "for the detection of ." One perplexing detail of this work was that, with their ground-breaking detection methods, they were detecting one-third to one-half as many neutrinos as expected, an issue known as the "." This shortfall was first thought to be due to experimental problems. But, once it was confirmed by Super-Kamiokande, the deficit was accepted as real.

The year prior to the Nobel, however, scientists announced a solution to the solar neutrino problem. It turned out that neutrinos oscillate among three forms (electron, muon and tau) and detectors were primarily sensitive to only electron neutrinos. For the discovery of these oscillations, the 2015 Nobel Prize in Physics was awarded to Takaaki Kajita of Super-Kamiokande and Arthur B. MacDonald of the Sudbury Neutrino Observatory.

Even with these Nobel Prize-worthy developments in research and equipment at their disposal, scientists can still detect only a few thousand neutrino events each year.

A new option for research

The research that Sturrock learned about in Tucson concerned fluctuations in the rate of decay of radioactive elements. The fluctuations were highly controversial at the time because it had been thought that the decay rate of any radioactive element was constant. Sturrock decided to study these experimental results using analytical techniques that he and Scargle had developed to study neutrinos.

In examining the radioactive decay fluctuations, the team found evidence that those fluctuations matched patterns they had found in Super-Kamiokande neutrino data, each indicating a one-month oscillation attributable to solar rotation. The likely conclusion is that neutrinos from the sun are directly affecting beta-decays. This connection has been theorized by other researchers dating back 25 years, but the Sturrock-Fischbach-Scargle analysis adds the strongest evidence yet. If this relationship holds, a revolution in neutrino research could be underway.

"It means there's another way to study neutrinos that is much simpler and much less expensive than current methods," Sturrock said. "Some data, some information, you won't get from beta-decays, but only from experiments like Super-Kamiokande. However, the study of beta-decay variability indicates there is another way to detect neutrinos, one that gives you a different view of neutrinos and of the sun."

Sturrock said this could mark the beginning of a new field in neutrino research and . He and Fischbach see the possibility of bench-top detectors that would cost thousands rather than millions of dollars.

The next steps for now will be to gather more and better data and to work toward a theory that can explain how all these physical processes are connected.

Explore further: Nobel-winning discovery of neutrino oscillations, proving that neutrinos have mass

More information: P. A. Sturrock et al. Comparative Analyses of Brookhaven National Laboratory Nuclear Decay Measurements and Super-Kamiokande Solar Neutrino Measurements: Neutrinos and Neutrino-Induced Beta-Decays as Probes of the Deep Solar Interior, Solar Physics (2016). DOI: 10.1007/s11207-016-1008-9

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3 / 5 (4) Nov 09, 2016
The movie '2012' has a similar (or the same?) effect being caused by neutrinos reacting with radioactive materials in the earth's core.
1 / 5 (2) Nov 09, 2016
Neutrino light to photon light converting matrix

Apparatus for viewing in neutrino light first uses microwaves to create neutrino force differentials on piezoelectric material. The force differentials are used by elements of a matrix to create pixels of a two dimensional picture for use in viewing of underground structures from a satellite. In another form pixels are formed on an LCD display for direct human viewing.

3.7 / 5 (3) Nov 09, 2016
So, in the space of a couple of decades, detecting neutrinos goes from 'cannot be done' to 'wow' to potentially 'Science Fair' tech !!

The old SciFi line about 'tuning the neutrino detectors' to detect nuclear reactors may just be coming true...
3.7 / 5 (3) Nov 09, 2016
So, in the space of a couple of decades, detecting neutrinos goes from 'cannot be done' to 'wow' to potentially 'Science Fair' tech !!

The old SciFi line about 'tuning the neutrino detectors' to detect nuclear reactors may just be coming true...

Don't hold your breath. The link provided is for a bogus patent application in 2003. I.e. It is just more pseudoscience. However, the link is worth reading because the "science" is really funny.
Nov 09, 2016
This comment has been removed by a moderator.
1 / 5 (3) Nov 09, 2016
"However, the link is worth reading because the "science" is really funny"

In what way is it funny? The patent holder was involved with military R&D, and developed technologies that still help protect the US power grid. .
2.3 / 5 (3) Nov 09, 2016
Hi hawkingsbrother. :)
The movie '2012' has a similar (or the same?) effect being caused by neutrinos reacting with radioactive materials in the earth's core
Yes, the global warming can be explained with it. I don't understand, what prohibits the scientists to test the speed of radioactive decay with known artificial neutrino sources. They're already doing way more nonsensical and expensive experiments.
As I have pointed out many times over the years, it isn't the 'inputs' that determines NET warming/cooling effects, it is the ATMOSPHERE (or ABSENCE of it) that determines NET effect of ALL 'inputs'.

Example, Mercury Planet: Despite huge SOLAR heat 'inputs', surface goes extremely COLD on 'night side' as it revolves; because it has no atmosphere of the type to INSULATE it (to prevent massive heat energy re-radiation/almost immediate loss to space).

So, it's Earth's atmospheric "LAG" effect that produces NET 'warming'; and more CO2 means more NET warming. :)
Nov 09, 2016
This comment has been removed by a moderator.
5 / 5 (5) Nov 10, 2016
"The atmosphere contains no radioactive elements, the water and earth crust does, so that most of heat gets released right there."

You missed the point. For analogy consider a fireplace that is heating your room only at day (sun). You can also have floor warming that is on always (geothermal heat). But without walls and roof (atmosphere) your room will be cold at night. The better insulation you have at waals and roof, the more stable your temperature will be (compare winter starry night with cloudy one). With more CO2 we have a better insulation, which means warmer Earth.
Nov 10, 2016
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4 / 5 (4) Nov 10, 2016
If the CO2 would serve as an thermal insulation, it would lead to cooling instead. The more CO2 the darker the atmosphere will be for infrared radiation

OK..some basics:

1) Not all incident radiation on Earth is infrared (visible, UV, gamma). CO2 is transparent to this. Of that incident light a large part is absorbed by the Earth's surface and reemitted as infrared (and you need to add all the human-made infrared - which is not negligible)
2) An insulation is not a reflector. It absorbes and stores the energy. A reflector would cool the Earth. An insulator warms it until saturation is reached. Yes there is an equilibrium point - but it's somwhere around the conditions on Venus.

And the darker objects not only better absorb the radiation, they also better radiate it back at night.

The atmosphere is not a flat plane. Reemitted IR can be reabsorbed in the volume of the atmosphere. The CO2 acts as an (unwanted) buffer system for keeping the energy trapped.
4 / 5 (4) Nov 10, 2016
In addition we have here negative feedback of global warming in atmospheric humidity, which precipitates into a clouds, which also reflect the heat well.

No. Water vapor is also a greenhouse gas. Very effective at trapping heat (though not as dangerous as CO2 since water dissociates quickly in the atmosphere while CO2 - being a very stable molecule - hangs arounds for hundreds of years. More clouds make the situation worse - not better (see again: Venus)

Albert Einstein: "Things should be as simple as possible, but not simpler"

I totally agree. But you really need to grok some very, very simple things before writing further posts.
Nov 10, 2016
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3.7 / 5 (3) Nov 10, 2016
Apparently the contribution of carbon dioxide is completely negligible and the water content drives global warming way more reliably

You are aware that pretty much every study and experiment done on this subject disagrees with your claim?

he reflection of clouds contributes to energy loss by 60%,

Erm..the image says 20%. Learn to read images/graphs. The 60% is 'RADIATED from clouds and atmosphere'. Note the RADIATED (not 'reflected') and note the AND ATMOSPHERE"

Jeez,man..if you can't even read kindergarten level graphs do you really think your assessment of
Whole the CO2 based anthropogenic global warming theory sits on very fuzzy numbers

Holds any water (pun intended)?

Make conclusions yourself.

Done. You failed all math/physics/reading comprehension courses you ever attended.
Nov 10, 2016
This comment has been removed by a moderator.
Nov 10, 2016
This comment has been removed by a moderator.
5 / 5 (3) Nov 10, 2016
Another 20% is reflected from clouds, which means, whole 80% of heat flux balance depends on the amount of clouds. You see. clouds keep heat IN. that is why cloudy nights are warmer than cloudless ones.
Man, this is so simple stuff. Go outside - you can check out that you're completely wrong yourself just by opening your window.

The rest of your posts is a garbled mess of misunderstanding and wrong math. No. heat retention/reflection/radiation doesn't work that way you imagine.

take some basic phyisc (and before that take some basic math....and before that take some basic reading comprehension classes)...then get back here. Until then there's really no point.
not rated yet Nov 14, 2016
Perhaps nuetrinos are responsinble for all radiactive decay through interacting with quarks?
Nov 25, 2016
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