Ten years after discovering the Higgs boson, the Large Hadron Collider (LHC) is about to begin smashing protons at unprecedented energy levels in its quest to uncover more secrets about how the universe works.
The world’s largest and most powerful particle collider resumed operation in April after a three-year hiatus to allow upgrades in preparation for its third run. The European Organization for Nuclear Research (CERN) announced at a press conference last week that it will operate at a record energy of 13.6 trillion electronvolts, 24 hours a day for nearly four years, starting Tuesday.
Two beams of protons (particles in the nucleus of an atom) will be sent in opposite directions at almost the speed of light around a 27-kilometer ring buried 100 meters below the Switzerland-France border. The resulting collisions will be recorded and analyzed by thousands of scientists as part of various experiments, including ATLAS, CMS, ALICE and LHCb, which will use this augmented power to probe dark matter, dark energy and other fundamental mysteries.
“We aim to deliver 1.6 billion proton-proton collisions per second” for the ATLAS and CMS experiments, said Mike Lamont, CERN’s head of accelerator and technology. He also added that this time the proton beams will be narrowed to less than 10 microns (a human hair is about 70 microns thick) to increase the collision rate.
The new amount of energy will allow further research into the Higgs boson, first observed by the Large Hadron Collider on July 4, 2012. This discovery nearly revolutionized physics, in part because the boson fits within the Standard Model, the mainstream theory of all the fundamental particles that make up matter and the forces that govern them. But some recent findings have raised questions about the Standard Model, and the newly updated collider will delve deeper into the Higgs boson.
“The Higgs boson is relevant to some of the deepest open questions in fundamental physics today,” says Fabiola Gianotti, CERN managing director, who first announced the boson’s discovery a decade ago.
Compared to the collider’s first test to discover the boson, there will be 20 times more collisions this time around. “This is a significant increase that paves the way for new discoveries,” Lamont says.
Joachim Mnich, head of research and computing at CERN, says there is more to learn about the boson: “Is the Higgs boson really a fundamental particle or a compound? Is it the only Higgs-like particle in existence, or are there others?”
Past experiments have identified the mass of the Higgs boson, as well as more than 60 compound particles, such as the tetraquark predicted by the Standard Model. But Gian Giudice, head of CERN’s theoretical physics division, says observing particles is only part of the job: “Particle physics doesn’t just want to understand how it happens; our goal is to understand why.”
One of the Large Hadron Collider’s nine experiments is ALICE, which studies matter in the first 10 microseconds after the Big Bang, and LHCf, which uses collisions to simulate cosmic rays.
After this work, the collider will return as the High Brightness LHC in 2029, increasing the number of detectable events by a factor of 10.
To go one step further, scientists are planning the Future Circular Collider, a 100-kilometer ring aimed at reaching energies of 100 trillion electron volts.
But for now, physicists eagerly await the results of the third run of the Large Hadron Collider. CERN says that “a new season of physics is beginning”.
30632
