The Large Hadron Collider (LHC) is a marvel of modern particle physics that has enabled researchers to plumb the depths of reality. Its origins stretch all the way back to 1977, when Sir John Adams, the former director of the European Organization for Nuclear Research (CERN), suggested building an underground tunnel that could accommodate a particle accelerator capable of reaching extraordinarily high energies, according to a 2015 history paper by physicist Thomas Schörner-Sadenius.
The project was officially approved twenty years later, in 1997, and construction began on a 16.5-mile-long (27 kilometer) ring that passed beneath the French-Swiss border capable of accelerating particles up to 99.99 percent the speed of light and smashing them together. Within the ring, 9,300 magnets guide packets of charged particles in two opposite directions at a rate of 11,245 times a second, finally bringing them together for a head-on collision. The facility is capable of creating around 600 million collisions every second, spewing out incredible amounts of energy and, every once in a while, an exotic and never-before-seen heavy particle. The LHC operates at energies 6.5 times higher than the previous record-holding particle accelerator, Fermilab's decommissioned Tevatron in the U.S.
The LHC cost a total of $8 billion to build, $531 million of which came from the United States. More than 8,000 scientists from 60 different countries collaborate on its experiments. The accelerator first switched on its beams on September 10, 2008, colliding particles at only a ten-millionth of its original design intensity. Continue reading from Live Science
Large Hadron Collider (LHC) is the world’s most powerful particle accelerator. The LHC was constructed by the European Organization for Nuclear Research (CERN) in the same 27-km (17-mile) tunnel that housed its Large Electron-Positron Collider (LEP). The tunnel is circular and is located 50–175 metres (165–575 feet) below ground, on the border between France and Switzerland. The LHC ran its first test operation on September 10, 2008. An electrical problem in a cooling system on September 18 resulted in a temperature increase of about 100 °C (180 °F) in the magnets, which are meant to operate at temperatures near absolute zero (−273.15 °C, or −459.67 °F).
Early estimates that the LHC would be quickly fixed soon turned out to be overly optimistic. It restarted on November 20, 2009. Shortly thereafter, on November 30, it supplanted the Fermi National Accelerator Laboratory’s Tevatron as the most powerful particle accelerator when it boosted protons to energies of 1.18 teraelectron volts (TeV; 1 × 1012 electron volts). In March 2010 scientists at CERN announced that a problem with the design of superconducting wire in the LHC required that the collider run only at half-energy (7 TeV). The LHC was shut down in February 2013 to fix the problem and was restarted in April 2015 to run at its full energy of 13 TeV. A second long shutdown, during which the LHC’s equipment would be upgraded, began in December 2018 and is scheduled to end in late 2021 or early 2022. The heart of the LHC is a ring that runs through the circumference of the LEP tunnel; the ring is only a few centimetres in diameter, evacuated to a higher degree than deep space and cooled to within two degrees of absolute zero. Continue reading from Encyclopedia Britannica
Weasel Apparently Shuts Down World's Most Powerful Particle Collider (NPR)
Brookhaven and the Large Hadron Collider (BNL)
'Ghost Particles' Detected Inside the Large Hadron Collider for the First Time (Live Science)
Inside CERN’s Large Hadron Collider (New York Times)
Has the Large Hadron Collider Finally Challenged the Laws of Physics? (New Scientist)
CERN Experiment Hints at New Force of Nature (The Guardian)
2021: A Year Physicists Asked, ‘What Lies Beyond the Standard Model?’ (The Conversation)
Exotic four-quark particle spotted at Large Hadron Collider (Nature)
Europe Unveils Successor to the Large Hadron Collider (Physics World)
