Physicists at CERN's LHCb experiment have reported evidence of a rare B0 meson decay into two muons, a process predicted by the Standard Model to occur once in every 10 billion decays.
By Hermes-Vector AI Desk
Physicists with the LHCb Collaboration at CERN’s Large Hadron Collider have announced evidence for an extremely rare particle decay that scientists have been searching for for more than four decades. The result agrees with the Standard Model of particle physics.
The decay involves the B0 (B0d or Bd) meson, a short-lived particle containing a beauty quark, which turns into two muons, described by Dr. Harry Cliff of the University of Cambridge’s Cavendish Laboratory as "the heavier cousins of the electron."
According to Dr. Cliff, "This process only happens for one in every ten billion beauty particles, so it’s incredibly difficult to find."
Key measurements regarding the B0 decay include:
In a paper submitted to the journal Physical Review X, Dr. Cliff and colleagues reported an excess of events with a statistical significance of 3.0 standard deviations. When combined with earlier data from the LHCb experiment, the significance rises to 3.2 standard deviations.
The researchers also measured a sibling process involving the heavier B0s meson decaying into two muons. This process is more common than the B0 decay but remains extraordinarily rare.
The findings were made using the upgraded Large Hadron Collider beauty experiment (LHCb), which can collect data at up to five times its previous rate. Since the upgraded detector began collecting data in 2024, scientists have used improved particle identification and machine-learning techniques to distinguish the rare decay from other collisions.
Major UK-built components include a silicon pixel detector, known as the Vertex Locator, which sits five millimetres from the LHC beams, and the Ring Imaging Cherenkov system, which identifies particles by measuring light produced when they travel through gas faster than light.
These measurements allow scientists to test the Standard Model with greater precision. Such research may reveal "cracks in the Standard Model that could point towards undiscovered particles or forces," according to UKRI, potentially offering insights into questions such as the nature of dark matter.
Sources
This article was drafted with AI assistance and checked against the sources above. Company claims are reported as claims. Cover image is AI-generated.
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