Scientists with their new experiment have come closer to test whether magnetic monopoles exist.
Using a decommissioned section of the beam pipe from CERN’s Large Hadron Collider, scientists examined a beryllium beam pipe section that had been located at the particle collision point for the Compact Muon Solenoid (CMS) experiment.
This pipe had endured radiation from billions of ultra-high-energy ion collisions occurring just centimeters away, according to researchers.
Unique opportunity to probe monopoles
The study was conducted with Scientists from the University of Nottingham, in collaboration with an international team. They revealed that most stringent constraints yet on the existence of magnetic monopoles, pushing the boundaries of what is known about these elusive particles.
One of the scientists claimed that the proximity of the beam pipe to the collision point of ultra-relativistic heavy ions provides a unique opportunity to probe monopoles with unprecedentedly high magnetic charges.
“Since magnetic charge is conserved, the monopoles cannot decay and are expected to get trapped by the pipe’s material, which allows us to reliably search for them with a device directly sensitive to magnetic charge,” said Aditya Upreti, a Ph.D. candidate who led the experimental analysis while working in Professor Ostrovskiy’s MoEDAL group at the University of Alabama.
Predictions suggested old piece of pipe might be the most promising place to find a magnetic monopole
“Could there be particles with only a single magnetic pole, either north or south? This intriguing possibility, championed by renowned physicists Pierre Curie, Paul Dirac, and Joseph Polchinski, has remained one of the most captivating mysteries in theoretical physics,” said Oliver Gould, Dorothy Hodgkin Fellow at the School of Physics and Astronomy at the University of Nottingham.
The beam pipe surrounding the interaction region of the CMS experiment was exposed to 184.07 μb−1 of Pb-Pb collisions at 2.76 TeV center-of-mass energy per collision in December 2011, before being removed in 2013. It was scanned by the MoEDAL experiment using a SQUID magnetometer to search for trapped magnetic modals MMs. No MM signal was observed, according to the study.
Two distinctive features of this study, published on Physics Review Letters, are the use of a trapping volume very close to the collision point and ultrahigh magnetic fields generated during the heavy-ion run that could produce MMs via the Schwinger effect.
These two advantages allowed setting the first reliable, world-leading mass limits on MMs with high magnetic charge. In particular, the established limits are the strongest available in the range between 2 and 45 Dirac units, excluding MMs with masses of up to 80 GeV at a 95% confidence level, said researchers in the study.
Oliver stated that despite being an old piece of pipe destined for disposal, the researchers’ predictions suggested it might be the most promising place on Earth to find a magnetic monopole.
The MoEDAL collaboration used a superconductive magnetometer to scan the beam pipe for signatures of trapped magnetic charge. Although they found no evidence of magnetic monopoles, their results exclude the existence of monopoles lighter than 80 GeV/c2 (where c is the speed of light) and provide the world-leading constraints for magnetic charges ranging from two to 45 base units, reported Phys.org.
