I am interested in table top experiments involving probes for strong force. I am an experimentalist and am looking for the answer to the following question- if I have a sea of ultra cold neutrons, then how interaction of them with each other manifest the underlying strong force signature? Is it possible that if I am able to hold a trapped ion or atom amidst such a sea and if the background neutrons interact with the atomic nucleus, then by monitoring the electronic levels, I can probe the underlying nature of strong force? Can a low energy probe for strong interaction be developed along these lines?
In Neutron stars, the density is much higher than what I guess is possible to develop in a lab. However, what I am interested to find out is whether interacting neutrons can effectively change some 'basic' property of neutrons such as magnetic moment or 'effective' mass of neutrons.
The densities of neutrons attained in traps are small. From http://www.phy.ornl.gov/nuclear/neutrons/workshop/Doyle_UCN_tn.pdf you can estimate ~ 1 neutron/cm^3 . The neutron-neutron scattering cross section is the order of 10^(-23) cm^2, and if you use a velocity of 1 km/s, the scattering rate per neutron is 10^(-18)/s. So neutrons, with a lifetime of ~ 10^3 s, have no chance of colliding with each under such circumstances. The neutron proton scattering length is a characteristic property of the strong force. It is known to about a part in a thousand, from measurements of neutron scattering by molecular hydrogen. These were carried out with bulk hydrogen that is at a much higher density than can be attained in an atom trap. So my guess is that trapped atom/ion systems don't have much potential for improving the knowledge of n-n or n-p scattering. Maybe they could provide useful information on neutron scattering by heavier nuclei - have a look at Sears' tabulation and see if there are any gaps: http://www.ncnr.nist.gov/resources/n-lengths/list.html
Thank you for the response. The presentation was quite helpful. The point of extremely low scattering probability was an interrogation point for me also, but I didnt know the estimates. I am trying to explore possibility of studying nuclear forces with some other parameter, other than scattering cross sections. As far as I know, scattering cross sections and decay lifetimes are the only two probes we have of nuclear interactions. I am trying to formulate a possibility of something other than that. Even in my mind it is not very well formulated, partially because of my limited knowledge of particle physics and high energy physics, especially QCD calculations. But intuitively for me it seems to be an interesting avenue to explore, something along the lines of collective behaviour of particles interacting under effects of strong forces. It might help to better understand the internal dynamics of a nucleus.
I am not yet sure how to achieve it experimentally though.
- Neutron-Neutron-Wechselwirkungen sind nicht oder nur in extrem geringen Maße zu erwarten, weil dabei kein stabilerer Teilchenzustand entstehen kann. (Zur Struktur der Teilchen und Kerne siehe auch: http://tinyurl.com/erkennwelt)
- Die Existenz von Neutronensternen setzt voraus, dass Neutronen der Gravitation unterliegen. Es ist aber davon auszugehen, dass die Gravitationskraft nur zwischen atomar strukturierten Teilchen bzw. atomar strukturierter Materie wirkt.
I have absolutely no idea what you wrote. Sorry I do not know german
Sorry, my english is bad. So I wrote better in german.
The objekt of your resarch, the neutron, has still some brainteaser. The great problem of such experiments is "to catch and hold" the neutrons. Besides they are very dangerous.
- Neutron-neutron-interactions are improbably. The outcome of it would be more instable particles as neutrons are. You can find informations about the real structure of particles and atomic nuclei here: http://tinyurl.com/erkennwelt (unfortunately in german)
- In my opinion gravitation appears only between atomic materieal an not between particles. I find a simple reason for it. Neutron stars would be instable, they exist only in theory. I know that the doctrine see this different and so I'm alone against the crowd.
Actually people do trap and cool neutrons in labs. However, pointed above by Charles Clark, the density of neutrons in such cases is very low to studying their interactions is hard. I am trying to develop basically a table top probe for strong forces, which should be able to give us much more control than normal collider experiments. I am currently not worried about gravity, I dont think, from some basic numbers, that gravity will be playing any significant role in the regime I am thinking of looking at. I am however interested in your doctrine. Is the website you sent contains your research?
The content of the website is my reasearch, in this case about particles and nuclei.
I think too, gravity is not significant in your experiments.
I'm puzzled about experiments with ultra clod neutrons. The speed of cold neutrons is about 2km/s. You must do your experiments at temperature about 0K, right? Otherwise the neutrons would fly away.
I think, two neutrons would especially interact by the time of decay of one of it. I hope, you will recognise many things.
interact - wechselwirken; so you can learn a litle german ;-)
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