LHCb doubly charmed baryon discovery
The LHCb Collaboration at CERN publicly announced the unambiguous discovery of the doubly charmed baryon Xi_cc++ at the European Physical Society Conference on High Energy Physics (EPS-HEP) in Venice, Italy, on July 17, 2026, confirming a particle long predicted by the quark model. As of July 2026, the LHCb Collaboration and other research groups are actively engaged in follow-up measurements and research on the Xi_cc++ and the Omega_cc+ baryon, which was discovered using 2024 data and announced on July 17, 2026. This groundbreaking observation, presented with a statistical significance of 12 standard deviations, confirmed a baryon composed of two charm quarks and one up quark, with a measured mass of approximately 3621 MeV. In March 2026, the LHCb Collaboration also announced the discovery of a new proton-like doubly charmed baryon composed of two charm quarks and one down quark. Researchers will continue to use future LHCb data to measure the properties of these newly discovered particles, including the Omega_cc+, completing the family of doubly charmed baryons predicted over 50 years ago.
Timeline
Want updates on this thread?
Track this storyTimeline of developments
July 2026 — 3 developments
LHCb Discovers Omega_cc+ Baryon, Completing Doubly Charmed Baryon Family
The LHCb collaboration has announced the discovery of the Omega_cc+ baryon, completing the family of doubly charmed baryons predicted over 50 years ago. This discovery was made using data collected in 2024 with the upgraded LHCb detector. Researchers will continue to use future LHCb data to measure the properties of these newly discovered particles.
LHCb Continues Research on Doubly Charmed Baryons, Measuring Properties and Searching for More
As of July 2026, the LHCb Collaboration and other research groups are actively engaged in follow-up measurements and research on the recently announced doubly charmed baryon, as well as the previously discovered Xi_cc++. Efforts include precisely determining its mass, lifetime, and various decay channels. Scientists are also conducting independent analyses and continuing searches for other predicted doubly heavy baryons to comprehensively map the heavy quark sector.
LHCb Announces First Unambiguous Discovery of Doubly Charmed Baryon Xi_cc++
The LHCb Collaboration at CERN publicly announced the unambiguous discovery of the doubly charmed baryon Xi_cc++ (pronounced "Xi-cc-plus-plus") at the European Physical Society Conference on High Energy Physics (EPS-HEP) in Venice, Italy. This groundbreaking observation confirmed the existence of a baryon composed of two charm quarks and one up quark, a particle long predicted by the quark model. The discovery was presented with a statistical significance of 12 standard deviations.
March 2026 — 1 developments
LHCb Announces Discovery of New Doubly Charmed Baryon with Two Charm and One Down Quark
In March 2026, the LHCb Collaboration at CERN announced the discovery of a new doubly charmed baryon, distinct from the previously observed Xi_cc++. This newly identified particle is described as proton-like and is composed of two charm quarks and one down quark. This finding further expands the known spectrum of exotic baryons and provides additional data points for testing theoretical models of quark confinement.
July 2017 — 4 developments
Xi_cc++ Discovery Opens New Frontier in Quantum Chromodynamics Research
The discovery of the Xi_cc++ baryon was hailed as opening an exciting new frontier in the study of Quantum Chromodynamics (QCD), the theory of the strong nuclear force. This unique particle, with its two heavy charm quarks, provides a novel system for probing the interactions between quarks and gluons, offering insights into how quarks bind together to form matter.
LHCb Confirms Xi_cc++ Baryon Composed of Two Charm and One Up Quark
The LHCb Collaboration confirmed that the newly discovered Xi_cc++ baryon is composed of two charm quarks and one up quark. This specific quark configuration makes it the first unambiguous observation of a baryon containing two heavy quarks. Understanding its composition is fundamental to classifying the particle within the Standard Model and testing Quantum Chromodynamics.
LHCb Determines Mass of Doubly Charmed Baryon Xi_cc++ at 3621 MeV
As part of its initial discovery, the LHCb experiment precisely measured the mass of the newly found Xi_cc++ baryon. The particle was determined to have a mass of approximately 3621 MeV (Mega-electron Volts). This measurement was a crucial characteristic, allowing physicists to compare the experimental observation with theoretical predictions for doubly charmed baryons.
LHCb Collaboration Publishes Detailed Paper on Xi_cc++ Baryon Discovery on arXiv
Concurrent with the conference announcement, the LHCb Collaboration submitted their detailed scientific paper, titled "Observation of the doubly charmed baryon Xi_cc++", to the arXiv preprint server. This submission provided the full experimental methodology, data analysis, and results, allowing the global particle physics community to scrutinize and build upon the discovery. The paper detailed the particle's decay into a Lambda_c+ and a K- pi+ pi+.
January 1970 — 1 developments
Theoretical Physics Predicts Existence of Doubly Charmed Baryons in 1970s
Quantum Chromodynamics (QCD) and the quark model predicted the existence of baryons containing two heavy quarks, such as doubly charmed baryons, starting in the 1970s. These theoretical predictions laid the groundwork for experimental searches for these exotic particles, which were expected to provide unique insights into the strong nuclear force.