The Large Hadron Collider (LHC) is officially entering a new stage as a ground-breaking ceremony at CERN celebrates the start of the civil-engineering work for the High-Luminosity LHC (HL-LHC): a new milestone in CERN’s history.
This major upgrade to the Large Hadron Collider will considerably improve performance by 2026 as it will increase the number of collisions in the large experiments and boost the probability of the discovery of new physics phenomena.
Inside the 27-km LHC ring, bunches of protons travel at almost the speed of light and collide at four interaction points. These collisions generate new particles, which are measured by detectors surrounding the interaction points.
By analysing these collisions, physicists are deepening our understanding of the laws of nature.
How will work to the Large Hadron Collider improve research?
Although the Large Hadron Collider can produce up to 1 billion proton-proton collisions per second, the HL-LHC will increase this number, referred to by physicists as ‘luminosity’, allowing almost 10 times more data to be accumulated.
Having this data will allow physicists to investigate rare phenomena and make more accurate measurements. For example, the LHC allowed physicists to unearth the Higgs boson in 2012, thereby making great progress in understanding how particles acquire their mass.
The upgrade will allow the Higgs boson’s properties to be defined more accurately, and to measure with increased precision:
- How it is produced;
- How it decays; and
- How it interacts with other particles.
Additionally, scenarios beyond the Standard Model will be investigated, including supersymmetry (SUSY), theories about extra dimensions and quark substructure (compositeness).
CERN Director-General Fabiola Gianotti said: “The High-Luminosity LHC will extend the LHC’s reach beyond its initial mission, bringing new opportunities for discovery, measuring the properties of particles such as the Higgs boson with greater precision, and exploring the fundamental constituents of the universe ever more profoundly.”
The HL-LHC project is an international endeavour involving 29 institutes from 13 countries and was identified as one of the main priorities of the European Strategy for Particle Physics, before the project was formally approved by the CERN Council.
Overall, more than 1.2km of the current machine will need to be replaced with many new high-technology components such as: magnets, collimators and radiofrequency cavities.
To achieve a higher collision rate, the HL-LHC requires: about 130 new magnets, 24 new superconducting focusing quadrupoles to focus the beam and four superconducting dipoles. Sixteen brand-new ‘crab cavities’ will also be installed.
What else can be done to enhance the machines ability?
Another key element increase the luminosity in the LHC is to enhance the machine’s availability and efficiency.
CERN’s Director for Accelerators and Technology, Frédérick Bordry said: “Audacity underpins the history of CERN and the High-Luminosity LHC writes a new chapter, building a bridge to the future,
“It will allow new research and with its new innovative technologies, it is also a window to the accelerators of the future and to new applications for society.”
During the civil engineering work, the LHC will continue to operate.