Plans to build the most powerful supercollider ever have taken a huge leap forward thanks to a breakthrough in muon beam control. If perfected, the method could increase the frequency of muon collisions enough to make them a viable option for supercollider experiments.
Currently, supercolliders smash together protons, electrons, or ions to unlock the secrets of the universe, whereas a muon-based collider would allow for the study of collisions at much higher energies. Ironically, such a device would not only be more powerful but would also be cheaper and easier to build, unlike the increasingly massive supercolliders already in use.
Previous to this discovery, controlling muons has proven particularly challenging. For a supercollider to work properly, engineers need to make sure that the subatomic particles they use actually collide. Now, a team of researchers from the Imperial College of London says they have discovered a new method of controlling muons that could finally make the dreams of an ultra-powerful supercollider a reality.
“Our proof-of-principle is great news for the international particle physics community, who are making plans for the next generation of higher-energy accelerators,” explained Dr. Paul Bogdan Jurj, a researcher from the Imperial College Department of Physics and the first author on a paper outing the team’s discovery. “It is an important development towards the realization of a muon collider, which could fit into existing sites, such as FermiLab in the United States, where there is a growing enthusiasm for the technology.”
How Physicists Use a Supercollider to Unlock the Secrets of the Universe
Although 20th-century theoretical physicists dreamt of a massively powerful particle accelerator to help them peer into the depths of the subatomic world, the world’s first supercollider, the Large Hadron Collider (LHC) in Switzerland, did not begin conducting experiments until September 2008. Four years later, the 27-kilometer-long, donut-shaped facility made world headlines when researchers announced the discovery of the previously theoretical Higgs Boson.
Twelve years later, finding the subatomic particle that gives other particles their mass remains the most significant discovery made by the multi-billion dollar facility. There are potential plans to build a larger, nearly 100 km long supercollider, but that facility is also projected to take years and cost immense amounts of money. Also, like the current LHC, that facility will be limited to colliding subatomic particles that are easier to control than muons.
Notably, a supercollider that slams together high-energy muons would be smaller and cheaper to build and operate. The technology would also unlock more powerful experiments that cannot be conducted even at CERN, offering physicists a 21st-century tool that doesn’t currently exist.
“Muon colliders would be more compact and therefore cheaper, reaching effective energies as high as those proposed by the 100km proton collider in a much smaller space,” explains the press release announcing the team’s experimental breakthrough.
How Controlling Muon Beams Could Enable More Powerful Experiments
To make a muon-based supercollider a reality, the Imperial College team looked at ways to control the flow of muons in a particle beam. Sometimes called muon-marshalling, this process has proven exceedingly difficult to achieve, leaving previous researchers unable to crack the subatomic code.
Summarized in the journal Nature Physics, the method discovered by the Imperial College researchers involves the use of magnetic lenses and energy-absorbing materials to “cool” the muon beams. Previous research has shown that cooling muons in this fashion tends to cause them to move toward the center of the beam.
In the new research, the team studied this effect more closely, evaluating the shape of the muon beam in more detail. They also studied how much space the beam itself occupied, a crucial component when trying to facilitate particle collisions.
As hoped, these experiments, carried out at the Muon Ionization Cooling Experiment (MICE) muon beamline at the Science and Technology Facilities Council (STFC) ISIS Neutron and Muon Beam facility located at the STFC Rutherford Appleton Laboratory in the UK, allowed the researchers to increase the density and location of muons in the beam. This breakthrough means that, in theory, these high-energy particles could be easier to control and smash together in a particle supercollider.
Next Steps Toward Building a Muon Beam Supercollider
Although the muon-marshaling experiments were a success, the researchers behind the discovery say there are still a number of steps needed to implement their work into building an actual muon-based supercollider. Still, the team also believes that breaking through the muon-marshalling problem has opened the door to such a facility’s creation.
“The clear positive result shown by our new analysis gives us the confidence to go ahead with larger prototype accelerators that put the technique into practice,” explained MICE Collaboration spokesperson Professor Ken Long from the Department of Physics at Imperial.
Next, Dr. Chris Rogers, a scientist based at STFC’s ISIS facility in Oxfordshire and the leader of the MICE analysis team, says they are now focused on developing the muon cooling system for a possible Muon Collider at CERN.
“This is an important result that shows the MICE cooling performance in the clearest possible way,” Rogers said. “It is now imperative that we scale up to the next step, the Muon Cooling Demonstrator, in order to deliver the muon collider as soon as possible.”
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.