Large Hadron Collider Smashes Protons, Sets Record
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The Large Hadron Collider (LHC) reached a much-anticipated milestone today when it began smashing subatomic particles together at half its maximum power.
Earlier this month the "big bang machine" had broken its own energy record when it sent two 3.5-trillion-electron-volt (TeV) proton beams racing in opposite directions around the collider's 17-mile-long (27-kilometer-long) underground tunnel.
Today, at 1:06 p.m. local time in Geneva, Switzerland, LHC operators smashed those beams of protons together to create a record-shattering 7-TeV collision.
Reaching this point has been "marvelous," said David Evans, a physicist at the University of Birmingham in the U.K. and head of the LHC's ALICE detector project.
"I've been involved in [the LHC] personally for over ten years ... It's like waiting ten years for Christmas to come," said Evans, who watched the collisions from the ALICE control center at the European Organization for Nuclear Research (CERN), which operates the atom smasher.
(See Large Hadron Collider pictures.)
Large Hadron Collider "Like a Child"
As the first data from the impacts were announced, physicists who had gathered at CERN applauded, jumped up and down, and clutched laptops displaying images of the collisions to their chests as if the computers were newborn babes.
A large part of the excitement at CERN—and around the world—was relief that the Large Hadron Collider's previous electrical problems have had no lasting effect on the machine's ability to perform as expected, said Ian Shipsey, a co-coordinator of the LHC Physics Center at Fermilab in Illinois.
"When the machine started to do its early testing last fall, everyone was on a knife's edge. Every time the machine had a little problem, everyone imagined that it might have a disastrous meltdown," said Shipsey, who watched the show from half a world a way.
(See "Worst Case: Large Hadron Collider Spawns Planet-Devouring Black Hole")
"Now there's a sense of relief mixed with joy, and everybody's pinching themselves to make sure that it's real."
Despite today's smashing success, it's anything but smooth sailing from this point on, said Richard Cavvanaugh, also a co-coordinator at Fermilab's LHC Physics Center.
After all, there's still much to be done to ready the machine for the types of experiments scientists have in mind.
"This is a fantastic machine, but it's also very complex. It's very much like a small child," Cavvanaugh said. "The child has just been born and we're learning how to raise it, and during the process the child is going to go through teething and adolescence before finally reaching maturity."
LHC Still Just Half Power
The current plan is to run the Large Hadron Collider at 7 TeV continuously for 18 to 24 months. Then the LHC will shut down for up to a year to prepare the machine for 14-TeV collisions—the atom smasher's maximum operating energy.
The LHC's record-breaking smashups could uncover evidence of dark matter, discover new forces in physics, unveil new dimensions, and even find the Higgs boson, aka the God particle, a theoretical particle that physicists think is responsible for mass in the universe.
(See also "Large Hadron Collider to Have 'Practical' Spin-Offs?")
"Two years of continuous running is a tall order both for the LHC operators and the experiments, but it will be well worth the effort," CERN Director General Rolf Heuer said in a statement.
"By starting with a long run and concentrating preparations for 14-TeV collisions into a single shutdown, we're increasing the overall running time over the next three years, making up for lost time, and giving the experiments the chance to make their mark."
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I mentioned at the end of my
post about the importance of science that as much as we're able to see and as vast as it is, we only know what about 4% of it is.
Of the 4 fundamental forces, three have been worked out and connected under a single unified theory, and each is said to be mediated by a gauge boson, a particle that is fundamentally connected with the force, but the hypothetical particle that mediates gravity has been elusive. The theoretical Higgs Boson, which bears the unfortunate nickname of the God Particle,
[correction]is thought to be the source of the mass of particles. Unfortunately, it is thought to be neutrally charged and doesn't interact with anything in a way that allows it to be directly observed. This is why we can't see most of the mass in the universe, and the only way to prove the existence of a Higgs Boson is to collide particles in a way that is thought to produce it, and observe the decay products of that collision. The reason for needing high energy is complex, but in simple terms, the higher the energy of the collision the more confident we can be that an observed event was the decay of a Higgs Boson and not something else. Once enough of these events are observed that it is almost impossible that the results came about due to chance, we can say we found it.
The top minds in many fields have come together and built the most complex machine ever to, among other things, find that missing 96% and give us an insight into what the universe is made of. As there is only one and there will only ever be one, it is its own prototype and has not been without some setbacks. The Large Hadron Collider is such a precise, sensitive piece of equipment that it has to be constantly calibrated to account for radio and gravitational interference from many sources. These include an expansion and contraction of the diameter of the 27km ring by roughly 1 millimeter just due to global tides. After this was accounted for, they discovered that the level of nearby Lake Geneva was interfering and calibrated for that.
Of course, such a project has it detractors. I referred to the nickname of "God Particle" as unfortunate because it implies that science is treading on the ground of religion, which is far from the case, but fundamentalists oppose research because of this misunderstanding. A quote by a scientist at CERN was taken out of context and we got a lot of hype about the possibility that the LHC could create a devastating black hole; the truth is that cosmic rays interact with the atmosphere so frequently at higher energies than are produced in the LHC that if a stable black hole could be produced at this energy, we wouldn't be around to build something so awesome. There was also an article earlier this year that took the unproven concept of retrocausality to an absurd extent and proposed that the Higgs Boson is so fundamentally unnatural that the LHC was sabotaging itself from the future. Opponents of the LHC are unfortunately misinformed or ignorant, often through no fault of their own since these are very abstract concepts that don't translate easily into layman's terms.
After years of tuning, a supermagnet quench that set it back months due to a flaw in wiring, and a brief loss of power when a seagull dropped a baguette on the power lines (such is the way of ultra precise instruments,) it all came together. This morning, a second calibration beam had to be injected after someone forgot to turn the detectors on for the first one, but everything turned out exactly as expected. At 1:06PM local time, two beams with a total energy of 7TeV were collided and produced usable data. Although the LHC has been setting records multiple times a day for the past few weeks, 7TeV (tera-electron-volts) is the highest energy produced by a particle accelerator and is the full operational voltage for the first two years of operation. In comparison, neutrons produced by fission in an atomic bomb peak at roughly 2MeV, 3,500,000 times less energy than was produced in this collision. This is important for reasons mentioned above and means that it's all revved up and ready to produce data.
Ladies and gentlemen, the Science has been turned up to 11. We're going to learn a lot from this. If you have any questions, I'll try to answer them. If I can't, I'll pass them on to someone I know who's working at the LHCb detector and see what he says.