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The LHC does what every good particle smasher does -- find a new type of subatomic particle

The Large Hadron Collider has finally began to fulfill its potential.  After a string of early malfunctions, the world's largest collider has set records for the highest energy particle collisions.  Now, even as the smashing continues, the hard part begins -- combing through the mountains of data looking for interesting discoveries.

At the top of their wish list is the legendary Higgs boson, nicknamed the "God Particle", by the more colorful media establishment.  The Higgs boson is a theoretically predicted particle that would confirm the standard model of particle physics, explaining why some particles have mass and others don't.  Alternatively if the supersymmetry model holds true, up to five Higgs boson variants could be observed, disproving some of the standard model's theory.

I. LHC Finds a New Particle -- but not the Higgs Boson, Yet

Well, some of the data collected thus far has been scoured through, and disappointingly no conclusive evidence of the Higgs boson emerged (some readings indicate the possible existence of the particle, but were inconclusive).  Instead researchers discovered a new kind of Chi (X) particle.

The Chi (X) particle is composed of a bottom quark (also known as a "beauty" quark) and its anti-particle equivalent, the anti-bottom quark.  

LHC Collision
A computer visualization of one the LHC's collisions.  Scientists must sift through the individual sea of particles (trails shown here), hunting for new ones. [Image Source: CERN/LHC]

Quarks are tiny subatomic particles, which make up the constituents of atoms  -- like electrons, protons, and neutrons.  Any particle made up of quarks is called a hadron.  Their are two kinds of hadrons -- those made up of three quarks (baryons) and those made up a quark/anti-quark pair (meson).  Since the new Chi particle is composed of a quark/anti-quark combination, it belongs to the meson subclass of the greater hadron family.

Mesons have integer spins, meaning that they are bosons (like the Higgs boson!).  Boson particles obey Bose-Einstein statistics.

Chi mesons have a isospin of 0 (which dictates their strong interactions) and a positive G-parity on that isospin.  Together this is represented in shorthand as 0+.  The previously discovered chi particles had positive (P) parity and C-parity, and angular momentum values ranging from 0 to 2.  The previously known Chi mesons are -- χb0(2P) (0+0++), χb1(2P) (0+1++), χb3(2P) (0+2++).

The new particle is a "higher energy" Chi particle, in that it has a higher angular momentum number of 3.  It's been dubbed χb(3P) -- (0+3++).  Given the mass of the bottom quark -- over four times the mass of a proton -- it is unlikely that the LHC would have enough energy to create higher energy Chi particles.

II. LHC Passes a Time-Honored Accelerator Rite of Passage

Andy Chisholm, a PhD student from Birmingham, England, who worked on the project told BBC News that the location of the new Chi particle was a lucky find.  He comments, "Analysing the billions of particle collisions at the LHC is fascinating. There are potentially all kinds of interesting things buried in the data, and we were lucky to look in the right place at the right time."

Finding its first particle is sort of a right of passage in the particle collider world.  Past accelerators like FermiLab's Tevatron (America's largest particle accelerator, now defunct as the American government does not like to spend even a fraction of its immense budget funding important scientific research)
labored for years or more before finding their first particle, then went on to find many more particles over a fruitful run.

First time
The first one is always the hardest. [Image Source: Universal Studios]

University of Birmingham physicist, Professor Paul Newman comments on this right of passage, stating, "This is the first time such a new particle has been found at the LHC. Its discovery is a testament to the very successful running of the collider in 2011 and to the superb understanding of our detector which has been achieved by the Atlas collaboration already."

Thus far at least 175 mesons have been discovered.  

With each new meson discovered physicists creep a bit closer to understanding the strong force.  This understanding helps them better known what to look for when trying to find the kind/kinds of Higgs boson(s) predicted by the standard and supersymmetry theories of particle physics.  In that sense the discover of the new Chi quark may not be a "pay dirt" hit so to speak, but it's also not entirely a wash in the Higgs boson chase.

It also provides a bit of validation and good publicity, desperately needed to help the public appreciate the value of the accelerator -- which cost approximately $4.4B USD to build, and another billion or so to operate.  Keeping the 17 mile, 28 km (circumference) accelerator productive will help it avoid a fate similar to America's Tevatron.  If they can do that, physicists can continue their merry hunt for the Higgs boson and a better understanding of how our universe works on the most fundamental level.

Sources: Arxiv [Printserver; CERN], BBC News

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By EricMartello on 12/27/2011 12:18:58 AM , Rating: 2
Though entirely short-sighted, the kid has a point. They're searching for the Higgs Boson not to make a major discovery in particle physics, but instead to affirm a series of conjectures and theories put forth over the last few decades.

You gets it. If they were conducting this research to actually figure out how to make something better, rather than "aimlessly" prodding tired ideas in the hopes of securing additional research funding then I'd be more supportive of the LHC and similar efforts.

Consider 500 years ago (I'd say 600 years ago, but the Dark Ages/Catholic Church set us back nearly a millennium). Everyone thought they had the world figured out.. The world was flat -- sail long enough, you'd go right over the edge. If you got a cut, and it got infected, you were touched by a bad spirit -- something which could only be 'cured' by going to church and splashing some tainted 'holy' water on it. Mental illness, just a sign of possession by evil spirits -- lock them away or euthanize them.. Wrong or not, we had all the answers then..

True, and if you look at how mainstream science is presented to the average idiot these days, it's not a whole lot different than religion was thousands of years ago. People in general have always lacked a capacity for critical thinking, but at least in the past they knew they were stupid.

Now you got idiots who are educated thinking they're geniuses because they can parrot something they heard their professor say...and these idiots tend to cause problems because the commoners see them as intelligent when in reality he just knows how to paint in color instead of only black and white.

Not saying there are not genuinely intelligent people participating in the world of science, but I am saying that ignorant people are being misled by something presented as science when it is largely just someone's belief.

Examples? I'd point at made-up "disorders" like ADHD, made-up "catastrophes" like global warming and inconclusive or theoretical ideas being passed along as fact simply because we are unwilling or unable to disprove them.

"I'm an Internet expert too. It's all right to wire the industrial zone only, but there are many problems if other regions of the North are wired." -- North Korean Supreme Commander Kim Jong-il

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