A Heavier Cousin of the Proton

The newly observed Ξcc+ is part of the same particle family as the proton, which was first identified in Manchester by Ernest Rutherford and his team between 1917 and 1919. While protons are made up of two up quarks and one down quark, the Ξcc+ differs by replacing the two up quarks with heavier charm quarks.

Figure 1. New Proton-Like Particle Discovered at Large Hadron Collider.

This finding also builds on Manchester’s long-standing role in particle physics. In the 1950s, researchers from the university were the first to detect a member of the Ξ (Xi) family, helping deepen scientific understanding of how quarks combine to form matter. Figure 1 shows New Proton-Like Particle Discovered at Large Hadron Collider.

Manchester’s Leadership in the LHCb Upgrade

Professor Chris Parkes, head of the Department of Physics and Astronomy at University of Manchester, led the international collaboration during the installation and early operation of the upgraded LHCb detector. He also oversaw the United Kingdom’s role in the project for more than a decade, guiding it from initial approval through to completion.

Researchers in Manchester played a key role in designing and building essential components of the detector’s tracking system, including silicon pixel modules assembled in the university’s Schuster Building. These advanced detectors enable scientists to trace particle decays with remarkable precision, making it possible to detect signals from the Ξcc+ particle.

Reflecting on the achievement, Parkes highlighted the legacy of Ernest Rutherford, noting that his groundbreaking gold-foil experiment in Manchester reshaped our understanding of matter. He emphasized that today’s discovery continues that tradition, combining curiosity-driven research with cutting-edge technology at CERN.

A Detector Capturing 40 million Images Per Second

Dr. Stefano De Capua from the University of Manchester led the production of the silicon detector modules, describing the system as an ultra-fast camera. The detector captures images of particle collisions at a staggering rate of 40 million frames per second, using a specially designed silicon chip—technology that also has potential applications in medical imaging.

Researchers confirmed the existence of the Ξcc+ by analyzing how it decays into three lighter particles: Λc+, K–, and π+. These decay products were captured during high-energy proton–proton collisions at the Large Hadron Collider in 2024—the first year the upgraded LHCb detector operated at full performance.

From this data, scientists identified a distinct signal of around 915 events, measuring the particle’s mass at 3619.97 MeV/c². This value closely matches theoretical predictions based on a previously discovered related particle, the Ξcc++.

Resolving a Two-Decade Scientific Debate

For over twenty years, physicists questioned earlier claims of detecting the Ξcc+, as those findings could not be independently verified. The new results from the LHCb experiment finally resolve this uncertainty, revealing a mass that differs from earlier reports but aligns with predictions derived from its known partner particle.

Next Phase of Research at CERN

Looking ahead, University of Manchester is playing a major role in the next phase of research at CERN, known as LHCb Upgrade 2. This stage will use the High-Luminosity LHC to gather significantly larger datasets, enabling even more precise investigations into rare and complex particles.

Source:SciTECHDaily

Cite this article:

Priyadharshini S (2026), Physicists Identify New Proton-Like Particle at Large Hadron Collider, AnaTechMaz, pp. 368