CERN's Most Powerful Atom Smasher To Get New Super Powers

% of readers think this story is Fact. Add your two cents.

The world’s most powerful particle collider is soon to become even more powerful: a massive overhaul is expected to increase the luminosity of the Large Hadron Collider by a factor of 10. An EU-funded design study has shaped key innovations that will underpin the new configuration planned for 2026, which include new magnets and transmission lines.

High luminosity is the defining feature of the next major upgrade of the Large Hadron Collider, as reflected in the name HiLumi LHC: this four-year design study was launched in November 2011 to harness the required technologies. The ramp-up will greatly improve the collider’s capabilities, enabling particle physicists to explore fleeting phenomena at the heart of matter in much greater detail, says project coordinator Lucio Rossi of the European Organization for Nuclear Research (CERN).

The collider’s enhanced capabilities will also greatly increase researchers’ chances of illuminating physics beyond the Standard Model, which encompasses the fundamental building blocks of everything we see.

Credit:  Daniel Dominguez & Maximilien Brice

“We know that the Standard Model of particle physics, for all its merits, is highly incomplete,” says Rossi. It doesn’t, for example, explain the nature of dark matter, a hypothetical substance that is thought to be far more abundant than the type of matter detected so far.

A closer look at the fabric of the universe

In the LHC, beams of particles — usually protons — travelling nearly at the speed of light are fired towards each other, enabling researchers to study the events that unfold when the particles collide. Luminosity, in this context — or integrated luminosity, to be precise — is an indication of the number of such collisions produced in a given timeframe.

Increasing the luminosity thus essentially means generating more collisions, says Rossi. And this, in turn, entails work on the beam, and more specifically on the individual 30-cm segments — or bunches — that compose it.

In the high-luminosity LHC, Rossi explains, the number of particles within each bunch will be doubled. The beams will also be more concentrated, as powerful new magnets will be installed to compress them even more than in the current configuration. These magnets will be based on niobium-tin (Nb3Sn), a superconducting material that has never been used in an accelerator so far, he notes.

In addition, so-called crab cavities will be built to tilt the bunches, ensuring that they will collide head on rather than at the current slight angle. This course correction will further improve the chances of particles from the two beams crashing into each other.

Along with the beam, the collimators will also be enhanced. These components, Rossi explains, are basically the LHC’s brakes: they protect the device from its own beam by keeping it contained. With the proposed upgrades, tighter requirements for this essential equipment had to be addressed.

Another advance is related to energy transmission. In the high-luminosity configuration, the converters will be located at a distance of 100 m from the ring, says Rossi. Innovative superconducting transmission lines are being developed to carry very large current to the magnets without losses along the way.

Increased discovery potential

The upgrade is expected to increase the LHC’s discovery potential by 30%, says Rossi. This is a massive advance for physics, he observes, and it reflects the LHC’s tradition of technology development beyond the state of the art. High luminosity has given a focus to a number of exciting advances that had never been geared to a concrete application before, he notes.

However, the collider’s new superpowers will not just derive solely from components designed by HiLumi LHC. Another major endeavour focused on the detectors that are used to observe the phenomena unleashed inside the ring. Several earlier EU-funded projects have also helped to pave the way towards high luminosity, as have the efforts of many other research teams around the world.

With the end of the design phase, prototyping for the new components is under way, and construction work preparing the site for the new configuration will start in 2018. Rossi expects the new incarnation of the collider to be operational from 2026.

The preparations for high luminosity have created outstanding training opportunities at CERN, enabling many young scientists and engineers to hone skills that are greatly appreciated by the private sector, Rossi notes. “This boost to budding careers is one of the main things we give back,” he concludes.The European Investment Bank (EIB) and the European Organization for Nuclear Research (CERN) have signed an EU-backed loan agreement worth 250 million Swiss francs (€230 million). This is the second EIB financing for the Geneva based research institute, following a previous loan of €300 million in 2002 to finance the building of the Large Hadron Collider (LHC).

The loan will finance the High Luminosity Large Hadron Collider (HL-LHC) project, the world’s largest and most powerful particle accelerator. It will enable CERN to continue to explore the domain of particle physics, which gives the physicists clues about how the particles interact, and provides insights into the fundamental laws of nature.Carlos Moedas, European Commissioner for Research, Science and Innovation, said: “This loan under Horizon 2020, the EU’s research funding programme, will help keep CERN and Europe at the forefront of particle physics research. It’s an example of how EU funding helps extend frontiers of human knowledge.”