The European Organization for Nuclear Research (CERN) outside Geneva has inaugurated a linear accelerator that injects and accelerates high-energy particle beams into the 27-kilometre circular Large Hadron Collider (LHC). The upgrade should eventually help experiments gather ten times more collider data.
On Tuesday, CERN announced the official launch of Linac 4, a 90-metre-long underground linear accelerator, which represents the first link in CERN’s accelerator chain and should deliver higher energy particle beams for many experiments.
CERN director-general Fabiola Gianotti said Linac 4 and the ongoing upgrade programme should “considerably increase the potential of the LHC experiments for discovering new physics and measuring the properties of the Higgs particle in more detail”.
The elusive Higgs boson, whose discovery secured the Nobel Prize for physics in 2013, answered fundamental questions about how matter attained mass. But it did not solve the riddle of what’s missing from the “standard model” of physics.
The CHF6.5 billion ($6.47 billion) LHC, conceived in the early 1980s, is the biggest particle collider ever built. It sits in a circular tunnel, 100 metres below the ground at CERN on the French-Swiss border, north of Geneva.
The Linac 4, which replaces a model in service since 1978, cost CHF93 million ($93 million) and took ten years to build. It should deliver to the LHC over three times the energy of its predecessor. This increase in energy, together with the use of hydrogen ions, will enable double the particle beam intensity to be delivered to the LHC, thus contributing to an increase in the luminosity of the LHC.
Ultimately, CERN scientists studying the particle collisions should be able to gather about ten times more data. This should lead to more accurate measurements of fundamental particles, as well as the possibility of observing rare processes, it said.
After an extensive testing period, Linac 4 will be connected to CERN’s accelerator complex during a technical shut down in 2019-20.