Atlas experiment is one of the two multifunctional experiments at the LHC Large Hadron Collider (LHC) has picked up tantalizing fluctuations that may - or - cannot be evidence of the long-awaited Higgs boson particle.But scientists stressed caution about these "excess events", because similar wrinkles have been detected before only to disappear after further analysis.
In any case, there is the subatomic particles is running out of places to hide, says the head of the European Organization for Nuclear Research (Cern), which runs the LHC.
He told BBC News the Collider had now ruled over "mass range," where might be the Higgs.
The new results are based on the analysis of data, as the great machine destroys beams of protons together at nearly the speed of light.
The main objectivesScientists from two different experiments (Atlas and CMS) based on the LHC are touring the remains of these collisions.
One of its main objectives is to look for hints of the Higgs, who is the last missing piece in the standard model, the most widely accepted particle physics theory.
Without the Higgs physics cannot explain why particles have mass. But despite the efforts of scientists working on both sides of the Atlantic to detect experimentally, the boson remains a theoretical particle subatomic.
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particle physics has a definition accepted by a "discovery": a cinco-sigma of certaintyThe number of sigmas (or standard deviations) is a measure of how unlikely is that an experimental result is simply down to random rather than an effectSimilarly real, throwing a coin and getting a number of heads in a row can be opportunity, rather than a sign of a "burden" coinThe "three sigma" level represents more than eight heads on the same probability of release in a rowFive sigma, on the other hand, it would be up to launching more than 20 in a rowA five sigma result it is very unlikely to happen by chance, and so an experimental result becomes an accepted discoveryThe standard model is a framework that explains how the known subatomic particles interact with each other. If the Higgs boson is not found, physicists would have to find another mechanism to explain where particles get mass of. It also requires researchers to change the standard model.Rolf-Dieter Heuer, director general of Cern, said that the amount of data collected was a factor of 20 major which had been assembled at the same time last year.
"With a reverse femtobarn cannot cover the entire mass region which allows for the Higgs boson," said Professor Heuer.
"However, experiments can now - unfortunately - exclude quite much of this permitted mass region."
The physicists who will most likely find the Higgs in the region of low mass - 114 GeV (gigaelectronvolts) and 140 GeV. While the gigaelectronvolt is a unit of energy in particle physics, mass and energy can be exchanged because of the idea of Einstein's equivalence (E = MC2).
FluctuationsProfessor Heuer said that searches in low masses had collected small fluctuations "here and there", but this is expected because physicists analyze small numbers across a number of different "channels".
"This is more interesting details that we collect," he explained.
News of the surplus of interesting events - seen team Atlas and CMS - outlined in HEP European Physical Society 2011 Conference here in Grenoble, France.
The largest surplus is seen in a mass of 145 GeV and is above the level of certainty two sigma. Another fluctuation is seen by the Atlas experiment at the greater mass of 250 GeV with a level of certainty two sigma.
A result of three sigma means about there is a possibility of one for every 1,000 that the result is due to some peculiarity of statistical data.
Five sigma means that it is a one in 1,000,000 chance that "bump" is only a coincidence and is generally the level necessary for a formal discovery.
Dave Charlton, who works in the experiment at the LHC Atlas, had been called "intriguing" excess of events.
But the physicist at the University of Birmingham, United Kingdom, told BBC News these "could go up to three sigma, or it might disappear".
Great Collider of hadrons is a great machine built in an underground tunnel that runs in a circle of 27 km in the Franco-Swiss border.
Accelerates two beams of particles protons in the speed of light in the circular tunnel and smashes les together at selected points around the underground ring collision. Looking at what occurs in these collisions of particles, physicists must be able to shed more light on the nature of the cosmos
HEP 2011 will be extended until July 29 in Grenoble.
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