Physics group corrals record number of neutrons into one place

Sep 26, 2011 by Bob Yirka report

(PhysOrg.com) -- Neutrons, the particles that along with protons, exist in the nuclei of atoms (except for hydrogen) have been intensely studied ever since their discovery in the 1930’s. And while many interesting developments have occurred as a result (fission reactions, etc) physicists have continued to be frustrated in their attempts to get a closer look at them, due to their not having an electric charge which could be used to hold them in place. Now however, a team working at the Institut Laue Langevin (ILL) in Grenoble, France, led by Oliver Zimmer, has found a way to do just that. In their paper published in Physical Review Letters they describe a technique they've developed that allows for bunching neutrons up in a group; as many as 55 per cubic centimeters, to get a better look at them.

To achieve this result, Zimmer and his team shot the neutrons into a container full of the coldest possible liquid, helium-4, to slow them down. Doing so brings them down to almost absolute zero which causes them percolate up through a valve which then corrals them into a single space. Using this process the team was able to amass five times the previous amount of neutrons in one place. Dr. Zimmer and his team have been working on the process and refining it since 2007. They believe that they can refine it even further to the point where they will be able to gather as much as 1000 cubic centimeters of the neutrons in one place.

The whole point behind such research is the belief that neutrons might hold the key to understanding some really tough physics problems, such as the nature of gravity or how the universe formed after the Big Bang. To get there though, other phenomena must first be studied and explained. One such example is that despite neutrons having no electric charge they still appear to have an electric dipole; but so far, because of the very nature of neutrons, no one has been able to measure it. By gathering more neutrons in one place and slowing them down in the process, researchers will hopefully be able to do exactly that, and more as gathering more neutrons in one place allows for more statistically precise observations and measurements.

Zimmer and his team believe the results they have achieved thus far might help answer some such questions, but acknowledges that denser groups of will still be needed to find the answers to the deeper questions.

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More information: Superthermal Source of Ultracold Neutrons for Fundamental Physics Experiments, Phys. Rev. Lett. 107, 134801 (2011) DOI:10.1103/PhysRevLett.107.134801

Abstract
Ultracold neutrons (UCNs) play an important role for precise measurements of the properties of the neutron and its interactions. During the past 25 years, a neutron turbine coupled to a liquid deuterium cold neutron source at a high-flux reactor has defined the state of the art for UCN production, despite a long history of efforts towards a new generation of UCN sources. This Letter reports a world-best UCN density available for users, achieved with a new source based on conversion of cold neutrons in superfluid helium. A conversion volume of 5 liters provides at least 274 000 UCN in a single accumulation run. Cyclically repeated operation of the source has been demonstrated, as well.

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User comments : 17

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Isaacsname
Sep 26, 2011
This comment has been removed by a moderator.
Skultch
5 / 5 (11) Sep 26, 2011
Hmmmmm, they didn't repel each other? Does the neutron-repulsion theory require extreme density for the repulsion to be significant?
Aranea_hirsuta
not rated yet Sep 26, 2011
They should try a similar experiment with anti-neutrons...not sure if they would have trouble generating them though.
Pressure2
4.2 / 5 (5) Sep 26, 2011
Hmmmmm, they didn't repel each other? Does the neutron-repulsion theory require extreme density for the repulsion to be significant?

These neutrons do repel each other but only because they still contain a little heat. They repel each other just like neutral gas molecules.
PosterusNeticus
4.6 / 5 (10) Sep 26, 2011
Hmmmmm, they didn't repel each other? Does the neutron-repulsion theory require extreme density for the repulsion to be significant?


The question is, how will he-who-shall-not-be-named respond to this article? Will he choose to ignore its inconvenient existence? Will he explain how it is "wrong"? Or will he spew a stream of rambling, bubbling crazy that has nothing to do with the topic and no connection at all to reality?
Callippo
3 / 5 (2) Sep 26, 2011
They bounce each other, but moving neutrons are the source of de Broglie wave too and their interaction could be more complex (quantized in particular).
omatranter
4.5 / 5 (17) Sep 26, 2011
"Does the neutron-repulsion theory require extreme density for the repulsion to be significant?"

No only for its acceptance.

My brethren, the cold conditions of this experiment just makes their nipples stick out and they huddle together for warmth, and the Huggs Bozo-on is the mediator of this farce.

"Therefore the Lord himself will give you [King Ahaz] a sign: The virgin will be with child and will give birth to a son, and will call him Immanuel." Isaiah 7:14
Immanuel = Immaculate Manuel, could it be that I am the NeoChrist?!
I may have to try a laying on of hands at NAMBLA Conference (Neutron Abhorrents Mandated By Laughable Assertions) to see if I can heal the sick
omatwankr
4.1 / 5 (9) Sep 26, 2011
"inconvenient existence?"

What! has Al Gore finally made a movie about me, the Illuminati swine

The virgin will be with child and will give birth to a son, and they will call him Immanuel which means, "God with us." Matthew 1:23
Vendicar_Decarian
4.4 / 5 (7) Sep 26, 2011
These researchers must be in on the conspiracy against the Neutron-Neutron repulsion that powers our neutron star sun.

They are corrupt and evil individuals in league with Statan worshipers and the Luciferian Illuminati.
omatwankr
4.4 / 5 (7) Sep 26, 2011
"They are corrupt and evil individuals in league with Statan worshipers and the Luciferian Illuminati."

You have seen the light, at last, my associates will bee in-touch with some paperwork, I must warn you our societies mandated underwear takes some getting use to.

A poem for this joyous occasion

My body is covered in lotion
It is so sexy to See
Neutron Repulsions a notion
That no-one believes but me

"O frabjous day! Callooh! Callay!"
Jabberwocky ??:?
TehDog
not rated yet Sep 26, 2011
"Does the neutron-repulsion theory require extreme density for the repulsion to be significant?"

No only for its acceptance.

My brethren, the cold conditions of this experiment just makes their nipples stick out and they huddle together for warmth, and the Huggs Bozo-on is the mediator of this farce.


I am so glad I wasn't drinking when I read that, would have meant a new keyboard :)
Skultch
not rated yet Sep 26, 2011
Hmmmmm, they didn't repel each other? Does the neutron-repulsion theory require extreme density for the repulsion to be significant?

These neutrons do repel each other but only because they still contain a little heat. They repel each other just like neutral gas molecules.


Is that just a property of normal fluid dynamics? Is that more about a closed system reaching balance and not a property of the particles, themselves? Is it the hypothesized dipole?
kaasinees
3.7 / 5 (3) Sep 26, 2011
These comments really made my day.
Mabus
1 / 5 (3) Sep 27, 2011
"led by Oliver Zimmer"

Thank God it's not the other Oliver!
Vendicar_Decarian
1 / 5 (1) Oct 01, 2011
"Hmmmmm, they didn't repel each other?" - Skelch

The fact that they haven't been observed by now is pretty convincing proof that they do repel each other through the well known principle of Neutron/Neutron Repulsion.
hush1
not rated yet Oct 02, 2011
The whole text was lifted from a counter-terrorist handbook.
If you replace the word neutron(s) with the word terrorist(s) it all makes sense.

hush1
not rated yet Oct 02, 2011
Or riot control handbook. And protestors for neutrons.
Robert_Wells
not rated yet Oct 11, 2011
comments made my day, thanks all