ScienceDaily (Nov. 3, 2010).Results of an experimental physicist from Fermilab's leading seemed to confirm the existence of a strange discovery that has been aged 20 years, perforating the standard model, which leads to the existence of a new elementary particle: a fourth flavor of neutrino.
New results are then further describes the violation of fundamental symmetries of the universe, who thought that the anti-matter particles behave similar to the material.
Neutrinos are elementary particles are neutral and comes from the radioactive decay of other particles. "Flavours" another of the neutrino is a neutral pair of electrons and her cousins the larger, muon and tau. Whatever the original flavors of neutrinos, particles are constantly moving from one type of flavor to another in a phenomenon called "neutrino flavor Oscillation."
An electron neutrino can change into muon neutrinos, and then back again into electron neutrinos. Scientists believe that there are three flavors of neutrinos. In the Mini Booster Neutrino experiments of this experiment, MiniBooNE abbreviated, scientists detected a displacement (oscillation) is more than that predicted if there were only three flavors.
"These results refer to the existence of either a new particle or styles that we've never imagined before," said Byron Roe, processor emeritus in the Department of Physics University of Michigan, and an author of a scientific paper on these results a new were recently published online by Physical Review Letters.
"The simplest explanation involves the addition of a neutrino-like particles, or sterile neutrinos, which do not have the normal weak interactions in neutrinos exist."
All three types of neutrinos are known to interact with matter primarily through the weak nuclear force (weak nuclear force), which causes them difficult to detect. And because it has been hypothesized that this fourth flavor will not interact through the weak force, which makes it increasingly difficult to find.
"The existence of sterile neutrinos may help to explain the composition of the universe," said William Louis, a scientist at Los Alamos National Laboratory who was a disciple of Roe apada S3 UM and is involved in the MiniBooNE experiment.
"Physicists and astronomers are looking for sterile neutrinos because they can explain some or even all of the dark matter (dark matter) in the universe," said Louis. "Sterile neutrinos may also help to explain the asymmetry of matter in the universe, or why the universe consists primarily of matter, not antimatter."
MiniBooNE experiment, a collaboration of 60 scientists at several institutions, conducted at Fermilab to check the results of the experiments the Liquid Scintillator Neutrino Detector (LSND), the fancy began in 1990. LSND is the first experiment to detect neutrino oscillations more than predicted by standard models.
Initial results from the MiniBooNE few years ago, based on data from a gunshot neutrino (open, shots antineutrino), does not support the results from LSND. Although, LSND experiments performed using antineutrino shots, so it is the next step for MiniBooNE.
These new results are based on data from the first three years on the antineutrino experiment with shots, and they give very different results from previous results. MiniBooNE antineutrino data shot turned out to support the results of the LSND findings. And the fact that the MiniBooNE experiments produced different results for the antineutrino and neutrino, in particular amaze the physicists.
"The fact that we see this influence on the antineutrino, and not in neutrinos make it more weird," says Roe. "These results mean that the addition of more serious on our standard model would be needed than the thought of the first results of LSND"
This result is like a violation of "charge-parity symmetry" of the universe, which states that the laws of physics run in the same way on the particle by particle pairs. Violation of this symmetry can only previously seen on the rare decay, but instead of neutrinos, Roe said.
Although these results hasi-a statistically significant and does support the LSND results, the researchers to carefully by stating that they need the results of a longer span of time, or additional experiments before physicists can leave the predictions of standard model
Scientific work is called "Event Excess in the MiniBooNE Search for?? ?? e oscillations. "Which will be published in the latest issue of Physical Review Letters.
The research was funded by Fermilab, the Department of Energy, and the National Science Foundation.
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