Monday, April 25, 2011

Rumor Sweeping World's Science Community that CERN's LHC has Detected the Higgs Boson

An article I found concerning the LHC, I thought it was pretty cool.
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A rumor has gone viral in the physics community that the world's largest atom smasher may have detected a long-sought subatomic particle called the Higgs boson, also known as the "God particle," based on an anonymous commentor posted an abstract of a leaked note on Columbia University physicist, Peter Woit's blog, Not Even Wrong.

The controversial rumor is based on what appears to be a leaked internal note from physicists at CERN's Large Hadron Collider (LHC), a 17-mile-long particle accelerator near Geneva, Switzerland. It's not certain at this point if the memo is authentic, or what the data it refers to might mean — but the note has sent the physics community into full buzz mode.
Some physicists say the note may be a hoax, while others believe the "detection" is likely a statistical anomaly that will disappear upon further study. But the find would be one the century's great achievements, if it turns out to be valid.

Here's the note in full as it appeared on Woit's blog, Not Even Wrong:

Internal Note

Report number ATL-COM-PHYS-2011-415
Title Observation of a γγ resonance at a mass in the vicinity of 115 GeV/c2 at ATLAS and its Higgs interpretation
Author(s) Fang, Y (-) ; Flores Castillo, L R (-) ; Wang, H (-) ; Wu, S L (University of Wisconsin-Madison)
Imprint 21 Apr 2011. – mult. p.
Subject category Detectors and Experimental Techniques
Accelerator/Facility, Experiment CERN LHC ; ATLAS
Free keywords Diphoton ; Resonance ; EWEAK ; HIGGS ; SUSY ; EXOTICS ; EGAMMA
Abstract Motivated by the result of the Higgs boson candidates at LEP with a mass of about 115~GeV/c2, the observation given in ATLAS note ATL-COM-PHYS-2010-935 (November 18, 2010) and the publication “Production of isolated Higgs particle at the Large Hadron Collider Physics” (Letters B 683 2010 354-357), we studied the γγ invariant mass distribution over the range of 80 to 150 GeV/c2. With 37.5~pb−1 data from 2010 and 26.0~pb−1 from 2011, we observe a γγ resonance around 115~GeV/c2 with a significance of 4σ. The event rate for this resonance is about thirty times larger than the expectation from Higgs to γγ in the standard model. This channel H→γγ is of great importance because the presence of new heavy particles can enhance strongly both the Higgs production cross section and the decay branching ratio. This large enhancement over the standard model rate implies that the present result is the first definitive observation of physics beyond the standard model. Exciting new physics, including new particles, may be expected to be found in the very near future.

Researchers on the Compact Muon Solenoid (CMS) experiment at CERN's Large Hadron Collider near Geneva, Switzerland, reported in January that they have seen hints of what may be the hot, dense state of matter thought to have filled the universe in its first nanoseconds of existence. The CMS detector has captured a signal thought to represent this quark-gluon plasma. Quarks are generally trapped in groups of two or three by the gluons that bind them, but in the moments after the big bang, the universe was so hot that they could escape, becoming a fluid of free quarks and gluons.

Whether this really is a quark-gluon plasma is still unknown, but the CMS team hopes to find an answer shortly. "What is happening may be fully understood in the next few months or year," says CMS spokesman Guido Tonelli.

"We're within a billionth of a second of the Big Bang," CERN spokesman James Gillies told AFP back in March, 2010. The new stage, dubbed "First Physics", marks only the beginning of an initial 18- to 24-month series of billions of such collisions.

The LHC, which is located in a tunnel under the Franco-Swiss border, ground to halt with a major breakdown within days of its launch in 2008. But the huge scientific experiment then passed several groundbreaking milestones since it was restarted from repairs last November.

Scientists around the world will sift through and process the data on a giant computer network, searching for evidence of a theorised missing link called the Higgs Boson, commonly called the "God Particle".

"In this kind of physics, what's important in order to observe new phenomena is to collect statistics," said CERN scientist Despiona Hatzifotiadu. "It will give us a clue of how we were created in the beginning," she added. The experiment also aims to shed light on "dark matter" and subsequently "dark energy", invisible matter or forces that are thought to account together for some 96 percent of the cosmos.

At this stage the LHC is still running on only partial power. It is designed to run collisions at twice the current energy -- 14 TeV, equivalent to 99.99 percent of the speed of light.

CERN is aiming to cross that threshold with the giant, cryogenically-cooled machine after 2011.

At full power the detectors in cathedral sized chambers should capture some 600 million collisions every second among trillions of protons racing around the LHC 11,245 times a second.

CERN researchers plan to keep the LHC running until the end of 2012, rather than 2011 as previously scheduled. The 27-kilometre collider at the particle-physics laboratory CERN near Geneva, Switzerland, had endured delays and a crippling breakdown before finally surging to life late in 2009, and physicists say it is now performing above expectations.

Predictions of mini black holes forming at collision energies of a few teraelectronvolts (TeV) were based on theories that consider the gravitational effects of extra dimensions of space. Although the holes were expected to evaporate quickly, some suggested that they might linger long enough to consume the planet. But scientists at the Compact Muon Solenoid (CMS) detector now say they found no signs of mini black holes at energies of 3.5–4.5 TeV. Physicist Guido Tonelli, the detector's spokesperson, says that by the end of the next run, the LHC should be able to exclude the creation of black holes almost entirely.

The possible creation of tiny, particle-sized black holes would be more exciting than the discovery of Higgs Boson, who's function is giving mass to the particles of matter. Real data from these experiments will rewrite the theorists' Guide to the Quantum Universe.

According to current physics these nano black holes could not be created at the energy levels the LHC is capable of producing. They could only be created if a parallel universe actually exists, providing the extra gravitation needed to generate the nano black holes.

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