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Large Hadron Collider ( a.k.a The Big Bang Machine). SES 4U0 R. ORR SEPT 2012. WHAT IS IT?. Large Hadron Collider (LHC) about 9000 of leading world scientists have been gathering in Europe to build one of the largest science experiments in history
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Large Hadron Collider(a.k.a The Big Bang Machine) SES 4U0 R. ORR SEPT 2012
WHAT IS IT? • Large Hadron Collider (LHC) • about 9000 of leading world scientists have been gathering in Europe to build one of the largest science experiments in history • this project is designed to unlock the secrets of the universe • it has taken 20 years to develop and has cost about $8 billion
PURPOSE… • scientists are trying to prove that tiny “Higgs” particles (subatomic particles) exist • they think these smallest building blocks of nature, and the forces that brought them together, will help explain why the universe has organized itself into so many different things
PURPOSE... • Just after the big bang, quarks and gluons – basic building blocks of matter – were not confined inside composite particles such as protons and neutrons, as they are today. Instead, they moved freely in a state of matter known as "quark–gluon plasma".
WHO? • CERN (European Organization for Nuclear Research) has brought more than 80 countries together (e.g. India, Iran, Israel, Pakistan, Palestine, USA) to work on the collider and everyone will share the scientific results
Largest Machinein the World... • The precise circumference of the LHC accelerator is 26 659 m, with a total of 9300 magnets inside. Not only is the LHC the world’s largest particle accelerator…qualify as the world’s largest fridge. All the magnets will be pre‑cooled to -193.2°C (80 K) using 10 080 tonnes of liquid nitrogen, before they are filled with nearly 120 tonnes of liquid helium to bring them down to -271.3°C (1.9 K).
HOW? • CERN has constructed one of largest and most sophisticated machines ever built to replicate what the universe may have been like a few nanoseconds after it was created • 1 nanosecond = 1 x 10-9 s = one billionth of a second • it is all going to happen in a 27 km tunnel found 100m underground (under rocks and mountains) on the border between Geneva, Switzerland and France
WHERE? • http://maps.google.ca/maps?hl=en&q=map+of+geneva+switzerland&ie=UTF8&ll=48.57479,3.779297&spn=15.763622,35.771484&z=4
How? • Two beams of subatomic particles called "hadrons" – either protons or lead ions – travel in opposite directions inside the circular accelerator, gaining energy with every lap. • The new findings are based mainly on the four-week LHC run with lead ions in 2011, during which the experiments collected 20 times more data than in 2010.
HOW FAST?!? • At full power, trillions of protons will race around the LHC accelerator ring 11 245 times a second, travelling at 99.9999991% the speed of light. Altogether some 600 million collisions will take place every second.
QUOTES…Curiosity killed the cat? • "I have to say, it is pretty stupid to take two things and throw them at each other as fast as you can and see what comes out," says scientist Bob Stanek, who has been working on the collider for 14 years. • Stanek says "It's in humans' interest to know everything, right? And why wouldn't you want to know that?"
QUOTES…Transporting in the future? "So, let me ask you this question: because we've studied the interactions of photons and electrons and elementary particles, we can understand how to take the light that bounces off of me and you into that camera and take that signal and put it into mom and pop's living room. Now, imagine, in 10 years, 20 years, will we be able to take, instead of our photons, me and you and put them in mom and pop's living room? So, you tell me, is that worth it?" Stanek asks. "Transport people?" Kroft asks. "You tell me. Is that worth it? Is that worth eight billion dollars?" Stanek asks. Asked if he thinks that could happen, Stanek replies, "I don't know enough right now. But I can't say it can't happen."
QUOTES…Purpose for us? • “So from a scientist's point of view it’s the biggest thing to happen in particle physics in say 20 or 30 years," Nahn says. • Asked what the average person is going to get out of this, Goldfarb tells Kroft, "The best thing is, we don't know."
HOW IT WORKS… • Two beams of invisible hydrogen protons will be driven around the tunnel in opposite directions inside ultra-high vacuum tubes propelled and guided by super conducting magnets, chilled with liquid helium to a temperature of -271oC, which is colder than deep space. • As the two beams approach speeds of light (3 x 108 m/s), they will collide at 4 different parts of the LHC.
HOW IT WORKS... • In the LHC heavy-ion programme, beams of heavy nuclei ("ions") collide at energies up to 30 times higher than in previous laboratory experiments. In these heavy-ion collisions, matter is heated to more than 100,000 times the temperature at the centre of the Sun, reaching conditions that existed in the first microseconds after the Big Bang. The aim of the heavy-ion programme at the LHC is to produce this matter at the highest temperatures and densities ever studied in the laboratory, and to investigate its properties in detail. This is expected to lead to basic new insights into the nature of the strong interaction between fundamental particles
FOUR DETECTORS… • There are 4 massive detectors where the actual collision of the subatomic particles takes place. One of them is seven stories tall - nearly 7.3 x 106 kg of lead, steel, wires, plastic and magnets that capture and record everything that's going on inside. "So you can race these little…protons around this track at the speed of light, smash 'em in together in a beam that's the width of a hair. And you can measure what happens in a billionth of a second?" Kroft asks Stanek. "Billionth of a second, actually 25 nanoseconds. So set the scale," Stanek says. "Here to there is 25 feet. Turn my flashlight on, by the time that beam reaches that wall, is the time that we have to have recorded all this information.“
CAMERA AND COMPUTERS… • A 60 megapixel camera inside the detector captures what's going on at 40 million frames a second • the digital data detected by layers of sensors can be converted into pictures the human eye can understand • info goes out to computers, then to labs and universities all over the world for analysis • there are so many sensors monitoring so many collisions that in just 1 yr, the collider is expected to generate 10x more data than all of the information now on the Internet
COMPUTERS/DATA... • The data recorded by each of the big experiments at the LHC will fill around 100 000 dual layer DVDs every year. To allow the thousands of scientists scattered around the globe to collaborate on the analysis over the next 15 years (the estimated lifetime of the LHC), tens of thousands of computers located around the world are being harnessed in a distributed computing network called the Grid.
TRUSTING THE DATA? • To make sure the results are valid, the two main detectors are entirely different • Two different teams have been ‘competing’ with each other to get the job done
“HIGGS” PARTICLE… • One of the things scientists are hoping to find with the help of the collider is called the "Higgs" particle • named after Peter Higgs, a professor in Scotland • Four decades ago, he theorized that there must be something in the universe that we can't see that gives things weight or substance
OR THE “GOD PARTICLE” • The Higgs particle is sometimes called the “God particle”… because it plays a very, very important role. In giving mass to the other particles, it allows solid structures, solid things, you, me, tables, chairs to exist. Without it, we couldn't." Gillies
WHAT IF THE HIGGS PARTICLE DOESN’T EXIST? • "If this particle exists, we should be able to definitively see it. And if it doesn't exist, then this model that we keep confirming over the last 30 years has a big hole in it," says scientist Steve Nahn. "But there's gonna be an explanation one way or the other?" Kroft asks. "Yes,” Nahn says. “When you disprove a theory…usually, more theories come to take it's place."
a.k.a….back to the drawing board, which is what science is all about—trial and error!!
GIANT BLACKHOLE?!? • They also hope to learn about black holes, the dark voids in the universe that swallow up stars. A group of fringe scientists believe the collider might even create a black hole that could swallow up the Earth, and they’ve filed suit to stop the project from going forward. James Gillies doesn't seem to be too concerned. Asked how he knows that the collider won't create a black hole, Gillies says "We don't know that it won't do that. But we know that … if it's producing these little black holes, then they are decaying, and they’re not doing anything dangerous to us." “Not going to swallow the earth?” Kroft asks Gillies. “No,” he says. “You’re sure of that?” Kroft asks. “Absolutely,” Gillies says.
MAKING HISTORY • Scientists at CERN say we only understand about four percent of the known universe, and it took a century to turn the discovery of electrons into an iPod. There’s not likely to be a eureka moment here. It may take years of analyzing data to produce the first results. But Bob Stanek believes the collider will go down in history, and not for swallowing the earth.
SEPT 19, 2008… • “Investigations at CERN following a large helium leak into sector 3-4 of the Large Hadron Collider (LHC) tunnel have confirmed that cause of the incident was a faulty electrical connection between two of the accelerator’s magnets. This resulted in mechanical damage and release of helium from the magnet cold mass into the tunnel.” CERN • Simply put….it was like a circuit breaker “flipped” and the electricity caused a helium leak • To be restarted in the spring of 2009
VIDEOS: • The LHC 2005 (6min): (Building of) http://cdsweb.cern.ch/record/1136724 • LHC 2008 (10min) (Overview) http://cdsweb.cern.ch/record/1129494 • First Beam Sept 10/08 (5min): (not avail.) http://cdsweb.cern.ch/record/1136209 • 60 Minutes Interviews Sept 28/08: The Big Bang (1:28 min), The Collider (12:49), A Universal Effort (1:40 min): (only 1st avail?) http://www.cbsnews.com/stories/2008/09/28/60minutes/main4483600.shtml
REFERENCES: • A Trip Inside the “Big Bang Machine” (Sept 28, 2008) Available: http://www.cbsnews.com/stories/2008/09/28/60minutes/main4483600.shtml • CERN Website http://public.web.cern.ch/public/
Pictures: • http://www.policespecials.com/forum/lofiversion/index.php?t78998.htmlhttp://thelunchmeat.blogspot.com/2008/03/large-hardon-collider-opens-up-black.html • http://www.boingboing.net/2007/07/12/big-science-porn-exc.html
2012 More Info... • LHC http://lhc.web.cern.ch/lhc/ but now on Twitter • VIDEO (1min) June 3, 2012 “The Higgs Particle” http://cdsweb.cern.ch/record/1459442 • VIDEO (4min) June 26 2012 “CERN NEWS : Are we there yet on the search for the Higgs boson ?” http://cdsweb.cern.ch/record/1458015 • VIDEO (1min) June 3 2012 “What is dark matter?” http://cdsweb.cern.ch/record/1459443 • VIDEO (1min) June 3 2012 “How we select and process data?” http://cdsweb.cern.ch/record/1459440 • VIDEO (2 min) June 2012 “Construction of the ATLAS detector ” http://cdsweb.cern.ch/record/1459438