The U.S. LHC Accelerator Program succeeded in testing a new superconducting high-field quadrupole magnet known as HQ02a last week in an international project to which Lawrence Berkeley National Laboratory contributed.
The new magnet can operate at higher magnetic fields and at a wider temperature range than conventional high-field magnets can, because it is made out of niobium tin rather than niobium titanium. Because more data points can be collected using the new technology, scientists aim to use the new magnet with the Large Hadron Collider in order to make more detailed observations of particle behavior.
“The goal of the U.S. LHC Accelerator Research Program is to enable more powerful colliders,” said GianLuca Sabbi, who is affiliated with the Berkeley lab and coordinated the project. “Higher field and larger bore will translate in stronger beam focusing and more proton collisions. This is a key element of the upgrade plan to increase the LHC integrated luminosity by 10 times.”
Although niobium tin is often used in superconducting magnets, the material is not commonly used in accelerators, because it is naturally brittle and can easily snap when bent into the coil shapes necessary for accelerators. Niobium tin also cannot withstand the disruptive and high energy activities of particle collision.
The breakthrough in this project was implementing the material for use in accelerators, specifically with the LHC. Researchers developed a technology that adopts a thick, aluminum-based support structure pretensioned at room temperature to increase the malleability and durability of the material rather than directly using the material.
The construction of this technology was a collaborative effort among Lawrence Berkeley National Laboratory, the U.S. Department of Energy’s Brookhaven National Laboratory, Fermi National Accelerator Laboratory and SLAC National Accelerator Laboratory in partnership with CERN, the European Organization for Nuclear Research. The new U.S. magnets will be implemented in CERN’s LHC in the future.
Niobium tin has a 60 to 70 percent higher critical field than niobium titanium, which was also part of the project.
“This study proved that the technology works,” said Eric Prebys of Fermilab, who has been the director of LARP for the past five years. “The next step is to build a prototype. The actual magnet is only about 1 meter long. For it to be implemented in the LHC, it needs to be much longer.”
Researchers said their main goal in the future is to build a prototype for the magnet. The program is currently transitioning from the research and development phases to the construction of the new focusing system for LHC.
But the HQ02a’s usage is not only restricted to the LHC. According to Sabbi, all types of accelerators can benefit from this magnet technology, including those used in the medical and industrial fields. It can also enhance machines such as MRI scanners, which apply superconducting magnets.
Contact Mark Tan at [email protected]