LHCb experiment

LHCb is an experiment set up to explore what happened after the Big Bang that allowed matter to survive and build the Universe we inhabit today

Fourteen billion years ago, the Universe began with a bang. Crammed within an infinitely small space, energy coalesced to form equal quantities of matter and antimatter. But as the Universe cooled and expanded, its composition changed. Just one second after the Big Bang, antimatter had all but disappeared, leaving matter to form everything that we see around us — from the stars and galaxies, to the Earth and all life that it supports.

  • End of the 2025 proton-proton collision run

    The proton–proton (pp) data-taking period for 2025 has just come to an end. Thanks to the commitment and expertise of members of the LHCb collaboration, the outstanding performance achieved throughout the entire pp run has been made possible. LHCb has successfully collected 11.8 fb-1 of high-quality pp data. The image on the left below shows…

  • The LHCb collaboration turns 30!

    In August 1995 a Letter of Intent was submitted for the LHCb experiment, the world’s first dedicated B-physics experiment exploiting the unique potential of high-energy hadron-hadron collisions. This year, the LHCb collaboration has marked the 30th anniversary of this event. Click the cartoon (by Adrien Miqueu) for a higher-resolution version. The bound state of a…

  • Special light-ion LHC runs

    The LHC carried out a special run programme early summer. First results were reported by the ALICE, ATLAS, CMS and LHCb experiments at the Initial Stages of High-Energy Nuclear Collisions conference. These results were also presented at a CERN seminar and reported in a CERN news. During these special runs LHCb successfully acquired proton-oxygen (pO)…

  • Searching for new physics with the flavour changing neutral current decay B0→K*μ+μ–

    Last week at the LHCC open session and this week at a CERN seminar, the LHCb collaboration presented the legacy results from Run-1 and Run-2 data of the angular distributions of B0→K*μ+μ– decays. The analysis of B0→K*μ+μ– decays presents a promising method for exploring the potential effects of undiscovered particles (see the CERN Courier article…

  • Observation of orbitally excited Bc+ states

    At a CERN seminar today, the LHCb collaboration announced the first observation of orbitally excited Bc+ states, which are composed of a beauty-charm quark-antiquark pair. Within the expected mass range for excited 1P-wave Bc+ states a wide peaking structure was observed in the Bc+γ mass spectrum. The simultaneous discovery of the first heavy quark-antiquark bound…

  • The first dedicated Z-boson mass measurement at the LHC

    Today, the LHCb collaboration submitted for publication a paper reporting the first dedicated Z-boson mass measurement at the LHC using Z→μ+μ− decays. The data were recorded in 2016 and correspond to an integrated luminosity of 1.7 fb−1. Around 174×103 Z-boson events were selected. The image below shows the invariant mass of two muons from the…