DocM Posted March 3, 2012 Share Posted March 3, 2012 PhysOrg.... New picture of atomic nucleus emerges(PhysOrg.com) -- When most of us think of an atom, we think of tiny electrons whizzing around a stationary, dense nucleus composed of protons and neutrons, collectively known as nucleons. A collaboration between the U.S. Department of Energy's Argonne and Thomas Jefferson National Laboratories has demonstrated just how different reality is from our simple picture, showing that a quarter of the nucleons in a dense nucleus exceed 25 percent of the speed of light, turning the picture of a static nucleus on its head. "We normally picture a nucleus as this fixed arrangement of particles, when in reality there's a lot going on at the subatomic level that we just can't see with a microscope," said Argonne physicist John Arrington. Arrington and his colleagues used one of the Jefferson Lab's large magnetic spectrometers to look at the behavior of nucleons in some light atoms?deuterium, helium, beryllium and carbon. Physicists had long believed that "short-range correlations"?the interactions within nuclei that produced high-momentum nucleons?would largely reflect the density of the atom's nucleus, as they did in heavier nuclei. This hypothesis largely held true, except in the case of beryllium. Unlike the other atoms under investigation, beryllium contains two clusters of nucleons, each resembling a helium-4 nucleus. These nucleons, in turn, are bound to one additional neutron. Because of this somewhat unwieldy configuration, the nucleons in beryllium experienced a relatively high number of collisions despite being one of the least-dense nuclei. The nuclear "speed boost" observed by the researchers may have resulted from the interaction between the quarks that compose the nucleons that come into contact with one another. Each proton and neutron consists of three quarks that are bound extremely tightly to one another. When nucleons get too close together, however, the forces that usually constrain quarks can get disrupted, modifying the quark structure of the protons and neutrons or possibly even forming composite particles from the quarks of two nucleons. "Because the interaction between two closely spaced nucleons is responsible for both changes in momentum and quark behavior, I think it's imperative that scientists continue to study the phenomena that take place there," Arrington said. "Our next measurement will try to examine this question directly by taking a snapshot of the quark distributions at the moment when the nucleons are close together." Link to comment Share on other sites More sharing options...
Farstrider Posted March 3, 2012 Share Posted March 3, 2012 Pretty astounding stuff! Perhaps when modern scientists really work out what's going on, that these discoveries will propel us in a forward and positive direction. This is not to say we have not found some amazing discoveries but I think we've still got quite a way too go! Link to comment Share on other sites More sharing options...
Hum Posted March 3, 2012 Share Posted March 3, 2012 Sounds like me. Link to comment Share on other sites More sharing options...
Growled Member Posted March 4, 2012 Member Share Posted March 4, 2012 We know a lot more than we once did but we seem further and further away from knowing it all. The more we learn the more there is to learn, it seems. Link to comment Share on other sites More sharing options...
DocM Posted March 4, 2012 Author Share Posted March 4, 2012 Welcome to the rabbit hole :) Link to comment Share on other sites More sharing options...
neoadorable Posted March 6, 2012 Share Posted March 6, 2012 This is a gorgeous universe we have the privilege of inhabiting. Does this mean we can now build faster spaceships? I had to ask. Link to comment Share on other sites More sharing options...
DocM Posted March 6, 2012 Author Share Posted March 6, 2012 If you could harness the strong nuclear force (aka the quark-gluon force) directly without a nuclear reactor it might not get you light-speed, but it would get you a whole lot closer - and in a smaller package. There's some serious science to do here. Link to comment Share on other sites More sharing options...
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