The legendary theoretical physicist Joseph Polchinski once predicted the existence of magnetic monopoles, describing them as “one of the most faithful bets on not yet opened natural phenomena” with far-reaching implications for fundamental science. The Moedal collaboration at the Large Hadron Collider continues its quest to search for these particles possessing magnetic charges, aligning with theories that complement the standard model. Recently published research results available on the ARXIV preprint server have significantly narrowed the search parameters for these hypothetical particles.
Magnetic monopoles can be formed through interactions between protons or heavy ions. In proton collisions, they can arise from a single virtual photon (Drell-Yan mechanism) or the fusion of two virtual photons (photon fusion mechanism). Additionally, pairs of magnetic monopoles can be generated from a vacuum in intense magnetic fields produced during near-miss collisions of heavy ions, a process known as the Shvinger mechanism.
Since 2012, when data recording commenced, the Moedal collaboration has achieved several significant milestones. This includes the initial searches for magnetic monopoles in the collider, utilizing both the photon fusion and Shvinger mechanisms.
In the latest research endeavor, the MOEDAL collaboration focused on identifying magnetic monopoles and objects with high electric charges (HECOS) generated through the Drell-Yan and photon fusion mechanisms. The data collected during the collider’s second phase was analyzed using the Moedal detector system for the first time, signaling a crucial advancement in equipment.
The primary detector system has the capability to detect traces of magnetic monopoles and HECOS without interference from standard model particles, with these traces being analyzed using optical scanning microscopes at INFN Bologna. The secondary system comprises approximately one ton of traps designed to capture magnetic monopoles, which are then examined at ETH Zurich using a specialized Squid magnetometer.
Although the latest scans did not detect magnetic monopoles or HECOS, they did help establish more precise boundaries concerning the mass and production speed of these particles across different energy ranges. The range of acceptable values for magnetic charges has notably narrowed to a small interval near the fundamental unit known as the Dirac charge (GD). Furthermore, intensive analysis has ruled out the existence of these monopoles with masses exceeding approximately 3.9 trillion electron-volts (TEV), a scale currently beyond the capabilities of modern particle accelerators. Consequently, the pursuit of these elusive entities has entered a new phase characterized by stringent restrictions.