MEYRIN (Switzerland) (AFP) – The world’s most powerful particle accelerator will on Monday shutter operations for four years of renovations to dramatically boost its collision-capacity and the potential for unlocking one of the greatest mysteries of the Universe: dark matter._x000D_
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The Large Hadron Collider (LHC) – a 27-kilometre proton-smashing circular tunnel at the heart of Europe’s physics lab CERN near Geneva – has most famously been used to prove the existence of the Higgs boson, dubbed “the God particle”._x000D_
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In the tunnel, running about 100 metres below the French-Swiss border area, superconducting magnets and accelerating structures propel particles to extreme energies and then smash them together at phenomenal speeds._x000D_
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But from Monday, activity will stop, as the extraordinary device undergoes upgrades aimed to further increase the precision and intensity of particle collisions._x000D_
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Once completed, the enhanced particle smasher, donning the enhanced name of High Luminosity LHC (HL-LHC), is scheduled to begin operations in June 2030, and to run for about a decade._x000D_
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‘Many discoveries’ await_x000D_
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“This is a very important moment. From Monday, we will be entering a new phase,” HL-LHC project chief Markus Zerlauth told reporters._x000D_
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“We still have lots of physics questions without answers. There are still many discoveries to be made.”_x000D_
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The goal is to increase the “luminosity” – that is, the total number of collisions produced over a given period – by a factor of 10 compared to the LHC._x000D_
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The total cost of the upgrade is expected to tick in at 1.2 billion Swiss francs ($1.5 billion)._x000D_
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That will be covered by CERN membership fees, along with in-kind contributions, making up 10-15 percent of the total, including from the United States, Japan, Canada and China._x000D_
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The upgrade will require fully replacing the components in 1.2 kilometres of the 27-kilometre tunnel._x000D_
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New superconducting magnets, capable of further concentrating the particle beams, will be installed to increase the number of collisions._x000D_
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Once operational, between 140 and 200 collisions will occur each time two packets of particles meet inside detectors in the tunnel, up from 60 currently._x000D_
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Overall, “the increased number of collisions will allow us to collect up to 100 times more data”, Zerlauth said._x000D_
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The number of collisions will be so high – several billion per second – that it will be impossible to store all the data produced._x000D_
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Which collisions should be recorded will need to be selected in real time – a task that will be entrusted to artificial intelligence systems capable of identifying the most promising events._x000D_
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But “AI does not replace physicists”, insisted Nedaa-Alexandra Asbah, a research physicist at CERN’s ATLAS experiment, which helped discover the Higgs Boson using the LHC._x000D_
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“It is a powerful tool that helps us make better use of the data.”_x000D_
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Big Bang_x000D_
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The HL-LHC aims to deepen fundamental knowledge, which is CERN’s primary mission._x000D_
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“We want to look for new particles,” said Filip Moortgat, the operations coordinator for CMS – and the LHC detector designed to explore a wide range of physics fields, including the search for other dimensions and the quest for dark matter particles._x000D_
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Scientists believe that ordinary matter – such as stars, gases, dust, planets and everything on them – accounts for just five percent of the universe._x000D_
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The rest is believed to consist of dark matter (27 percent) and dark energy (68 percent) – two invisible components that scientists have yet to detect or directly observe._x000D_
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The 2012 discovery of the Higgs boson provided an important piece of the puzzle: it broadened science’s understanding of how particles acquire mass and earned physicists Peter Higgs and Francois Englert the 2013 Nobel Prize for Physics._x000D_
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Once the upgrade is completed, CERN hopes to dramatically expand its understanding of how the “God particle” works, with the HL-HLC expected to produce around 380 million Higgs bosons over its lifetime, compared to 55 million found since LHC operations began in 2008._x000D_
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The lab’s main hope meanwhile is to produce two Higgs Bosons simultaneously, which would be a first, and see them interact, Asbah said._x000D_
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This, she said, “may provide clues about how our Universe evolved shortly after the Big Bang”.
