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Call it the little particle accelerator that could. For the second time in weeks, the relatively small Tevatron at the Fermi National Accelerator Laboratory in Batavia, Ill., has found evidence of a possible new particle that would govern a new force in nature.
The latest finding, reported online April 6 at arXiv.org (arxiv.org/abs/1104.0699), is based on an unexpected excess in jets of particles produced at the accelerator.
A new particle similar to but heavier than the W boson and Z boson would explain the observed excess. W and Z bosons are fundamental particles that transmit the weak force, which is responsible for radioactive decay.
Less likely, says Fermilab theorist Dan Hooper, is the possibility that the new particle is a version of the long-sought Higgs boson. This version of the Higgs would be heavier than the one predicted by physicists’ standard model of particles and forces, and it would interact less often with matter. Considered the last missing piece of the standard model, the elusive Higgs boson was conceived of as a way to explain why some elementary particles have masses.
On the other hand, explaining the data may not require a new particle or a new force. The excess may have arisen from some aspect of ordinary particle interactions that researchers don’t understand, says Hooper, who was not involved in the new work.
The evidence is based on studies at the CDF experiment, one of two projects at the Tevatron, which collides a beam of protons with antiprotons moving at energies of nearly 1 trillion electron volts. In the new analysis, Titta Aaltonen of the University of Helsinki and a long list of collaborators homed in on collisions between 2001 and 2009 that produced a W boson along with two lightweight jets of particles, including electrons. Jets are relatively common and are a sign of quarks, which can’t be seen directly, but which fragment into other particles. The production of such jets in conjunction with the W boson is an essential starting point in probing physics beyond the standard model, Aaltonen and his colleagues note.
Looking at collision products at energies between 120 billion and 160 billion electron volts, the physicists saw an unexpected peak: They found about 250 more such events than predicted by the standard model.
There’s only a 0.076 percent chance that the excess is a fluke, the team notes in the paper. Though small, that percentage isn’t small enough to meet the standard criteria for proof in physics. In comparison, another unexpected recent finding at the Tevatron’s CDF, which also hints at a new elementary particle, has a smaller chance — 0.04 percent — of being wrong. But even that does not meet the standards of proof generally accepted in the field. CDF spokesperson Rob Roser of Fermilab does say, however, that the earlier finding “has a better chance of standing the test of time” than the excess jets result reported April 6.
Still, the jet excess captivates several theorists, including Hooper, because of the potential to actually find a new particle at the Tevatron and determine the particle’s mass. Visually, the peak energy of the excess, at about 145 billion electron volts, “jumps out at you,” indicating the mass of a possible new elementary particle, Hooper notes.
In an article that Hooper and colleagues posted online at arXiv.org on April 1 (arxiv.org/abs/1103.6035), they propose a particle that could explain both new findings. The team calculated that a hypothetical particle known as the Z’ boson, a heavier cousin of the Z boson with a proposed mass of 150 billion electron volts, could account for both results if the particle interacts strongly with quarks but avoids interactions with electrons and their heavier brothers, muons.
Physicists are eagerly awaiting the results of an analysis by the Tevatron’s other experiment, known as DZero. If that experiment also finds a jet excess in the same set of collisions, it could elevate the detection from a mere curiosity to a true discovery, Roser says. It would also constitute a last hurrah for the Tevatron, which will stop operation at end of the September due to budget cuts.
Found in: Atom & Cosmos
- R. Cowen. Remodeling the standard model. Science News Online, April 1, 2011. [Go to]
- CDF Collaboration, T. Aaltonen, et al. Invariant Mass Distribution of Jet Pairs Produced in Association with a W boson in ppbar Collisions at sqrt(s) = 1.96 TeV. arXiv:1104.0699v1. Posted April 6, 2011. [Go to]
- M.R. Buckley et al. Light Z' bosons at the Tevatron. arXiv:1103.6035. Posted April 1, 2011. [Go to]
- Aaltonen et al. Evidence for a mass dependent forward-backward asymmetry in top quark pair production. arXiv:1101.0034v1. Posted January 3, 2011. http:// arXiv:1101.0034v1
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A.
UNRAVEL COMPLEXITIES OF GENETICS.
Extend Evolution/Natural Selection Backward To Genes/Genomes, BOTH ARE ORGANISMS.
Again, Correct Some Figments Of Science Imagination
pulse.yahoo.com/_2SF3CJJM5OU6T27OC4MFQSDYEU/blog/articles/273273?listPage=index&bb=0
1. Dark energy and matter YOK. Per E=Total[m(1 + D)] all the energy and matter of the universe are accounted for.
Adopt space-massdistance concept, mass-to-enrgy reconversion.
2. Higgs Particle YOK. Mass forms below some value of the above D.
3. Galactic clusters formed by conglomeration?
Galactic clusters formed by Big-Bang's dispersion, evidenced by their Newtonian behaviour including expansion acceleration.
4. The universe expansion is fueled by the mass-to-enrgy reconversion. Eventually, as expansion will slow down, will run out of massfuel, gravity will overcome expansion and initiate empansion back to singularity. The universe is a cyclic array of energy-mass dualism, between all-energy and all-mass poles, under omnipresent gravity.
5. Natural Selection is a trait of organisms, life?
No. Natural selection is ubiquitous for ALL mass formats, all spin arrays. It derives from the expansion of the universe. All mass formats, regardless of size and type, from black holes to smallest particles, strive to increase their constrained energy in attempt to postpone their own reconversion to energy, to the energy that fuels cosmic expansion.
6. Life is an enigma?
Life is just another type of mass array, a self-replicating mass array. Earth life is a replicating RNAs mass. It has always been and still is an RNA world. ALL Earth's organisms are evolved RNAs, evolved for maintaining-enhancing Earth's biosphere, for prolonging RNAs survival.
7. Cells are Earth-life's primal organisms?
NO. Earth's life day one was the day on which RNA began replicating. RNAs, genes, are ORGANISMS. And so are their evolved templates, (RNA and DNA) genomes, ORGANISMS, as evidenced by life's chirality and by life's sleep.
8. Circadian Schmircadian sleep origin?
Sleep is inherent for life via the RNAs, the primal Earth ORGANISMS originated and originally active only under direct sunlight, in their pre-metabolism genesis era.
9. Epigenetics are heritable gene functions changes not involving changes in DNA sequence?
The "heritable or enduring changes" are epiDNAtics, not epigenetics. Alternative splicing is not epigenetics, even if/when not involving alteration of the DNA sequence. Earth life is an RNA world.
10.Genetics drive biology and culture modifications?
NO. It is culture that modifies genetics, not genetics that modifies culture. Culture modifies genetics simply via the evolutionary natural selection process of the RNA ORGANISMS. Likewise many natural genetic changes are due to aging and/or circumstantial effects on the genes and/or genomes ORGANISMS, similar to aging and/or evolutionary processes in monocell communities or in multicelled organisms.
SCIENCE SHOULD UNFREEZE. SCIENCE SHOULD ADJUST ITS VISION, COMPREHENSION AND CONCEPTS.
Dov Henis
(Comments From 22nd Century)
the-scientist.com/community/user/profile/1655.page
Seed of Human-Chimp Genomes Diversity
pulse.yahoo.com/_2SF3CJJM5OU6T27OC4MFQSDYEU/blog/articles/53079
03.2010 Updated Life Manifest
the-scientist.com/community/posts/list/54.page#5065
Evolution, Natural Selection, Derive From Cosmic Expansion
darwiniana.com/2010/09/05/the-question-reductionists-fear/
Rethink Evolution/Natural Selection
darwiniana.com/2011/03/29/comment-from-dov-henis/comment-page-1/
==========================
B.
Quantum Mechanics Of Life
Life's Evolution Is The Quantum Mechanics Of Biology
pulse.yahoo.com/_2SF3CJJM5OU6T27OC4MFQSDYEU/blog/articles/271915?listPage=index&bb=0
From "Essence Of Quantum Mechanics"
pulse.yahoo.com/_2SF3CJJM5OU6T27OC4MFQSDYEU/blog/articles/245916?listPage=uncategorized
The universe, and life within it, are not just conglomerations of mechanisms. The universe, and life within it, have come into being by the nature of energy-mass dualism, and their fate, their final outcome, is governed by this dualism. The genesis and, most probable cyclic, existence of the universe are governed by the energy-mass relationship.
Energy-mass relationship governs also the routes, the mechanisms, of cosmic and life evolutions.
Mechanisms do not set/determine the classical physics fate states. Mechanisms are routes of evolution between classical physics fate states. Quantum mechanics are mechanisms, probable, possible and actual mechanisms of getting from one to other classical physics states WITHIN the expanse from cosmic singularity to the maximum expanded universe and back to singularity states.
The universe is the archetype of quantum within classical physics. This is the fractal oneness of the universe. Astronomically there are two physics. A classical Newtonian physics behaviour of and between galactic clusters, and a quantum physics behaviour WITHIN the galactic clusters.
Life's Evolution Is The Quantum Mechanics Of Biology.
UNRAVEL COMPLEXITIES OF GENETICS. Extend Evolution/Natural Selection Backward To Genes/Genomes.
BOTH ARE ORGANISMS.
The origin-reason and the purpose-fate of life are mechanistic, ethically and practically valueless. Life is the cheapest commodity on Earth.
It is up to humans themselves to elect the purpose and format of their life as individuals and as group-members.
Dov Henis
(Comments From 22nd Century)
Figments Of Science Imagination
pulse.yahoo.com/_2SF3CJJM5OU6T27OC4MFQSDYEU/blog/articles/273273?listPage=index&bb=0
"Rethink Evolution/Natural Selection"
darwiniana.com/2011/03/26/in-evolution-last-really-can-be-first/comment-page-1/
(From Wires, April 26)An eminent Indian physicist Monday questioned the authenticity of the reports that speak of the discovery of the Higgs boson also known as god particle that is believed to bestow mass on other particles. A leaked internal memo contains unconfirmed reports that one of the detectors at the Large Hadron Colliders at CERN near Geneva picked up signals that could be a ‘Higgs boson’ says the Telegraph. B.G.Sidharth of the B.M.Birla Science Centre at Hyderabad said he was very skeptical about this claim.
“This is unofficially leaked news – such a thing has happened before” Sidharth who has authored several books and published research papers on the subject said. He had come out with new theoretical findings recently that say that there is a new force of nature acting between particles and their anti-particle counterparts. This can be seen at very high energies and is very shortlived. A discovery matching this description has been announced by the CDF team at Fermilab’s Tevatron in Illinois. There is about a one in a thousand chance that this observation is a fluke. But given the theoretical background, the chances this is wrong is even less.
“In fact the latest LHC news (that says Higgs boson has been detected) has to be first verified and authenticated by the team itself, before any conclusion whatsoever can be drawn” he said adding ‘at present it is no more than a rumour’.
According to the Standard Model of particle physics the universe is composed of matter and anti matter. Besides there is an intermediary particle the ‘Higgs boson’ believed to bestow mass on matter and anti matter. The hypothetical elementary particle ‘Higgs boson’ predicted by the British physicist Peter Higgs some forty five years ago, has however not been directly discovered yet.
The Large Hadron Collider (LHC) at CERN created three years ago is likely to confirm or reject the existence of these new particles Some physicists even feel that the discovey of the Higgs would merely confirm the Standard Model, but physics would be more interesting in the absence of Higgs.
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