Muon colliders are both precision and discovery machines, but significant R&D is required before they can be considered candidates for a next collider.

Plenary talks during the opening of the open symposium of the European Strategy for Particle Physics highlighted the outstanding questions in the field, and the accelerator, detector and computing technologies necessary to tackle them.

On 26 February, a new solar power plant powering the SESAME light source in Jordan was officially inaugurated. In addition to being the first synchrotron-light facility in the Middle East region, SESAME is now the […]

The LHCb collaboration has discovered a new pentaquark particle, dubbed the Pc(4312)+, decaying to a J/ψ and a proton, with a statistical significance of 7.3 standard deviations. The LHCb data, first presented at Rencontres de Moriond […]

On 8 April, CERN unveiled plans for a major new facility for scientific education and outreach. Aimed at audiences of all ages, the Science Gateway will include exhibition spaces, hands-on scientific experiments for schoolchildren and […]

Ever since the 1970s, when the third generation of quarks and leptons began to emerge experimentally, physicists have asked if further generations await discovery. One of the first key results from the Large Electron–Positron Collider […]

On the morning of 21 March, at the 2019 Rencontres de Moriond in La Thuile, Italy, the LHCb collaboration announced the discovery of charge-parity (CP) violation in the charm system. Met with an impromptu champagne […]

The LHCb collaboration has released a much anticipated update on its measurement of RK – a ratio that describes how often a B+ meson decays to a charged kaon and either a μ+μ– or an […]

Data taking begins at Belle II • P2O targets Mediterranean Sea • FASER approved for LHC • First light for DESI • Squeezing rare kaon decays • No dark photons in NA62 • Ground breaking at PIP-II • Unnatural cross-fertilisation


The study of lead–ion collisions at the LHC is a window into the quark–gluon plasma (QGP), a hot and dense phase of deconfined quarks and gluons. An important effect in heavy-ion collisions is jet quenching […]

Serbia became the 23rd Member State of CERN, on 24 March, following receipt of formal notification from UNESCO. Ever since the early days of CERN (former Yugoslavia was one of the 12 founding Member States […]

Supersymmetry (SUSY) introduces a new fermion–boson symmetry that gives rise to supersymmetric “partners” of the Standard Model (SM) particles, and “naturally” leads to a light Higgs boson with mass close to that of the W […]

A world record for laser-driven wakefield acceleration has been set by a team at the Berkeley Lab Laser Accelerator (BELLA) Center in the US. Physicists used a novel scheme to channel 850 TW laser pulses through […]

The Japanese government has put on hold a decision about hosting the International Linear Collider (ILC), to the disappointment of many hoping for clarity ahead of the update of the European strategy for particle physics. […]

On 10 April, researchers working on the Event Horizon Telescope – a network of eight radio dishes that creates an Earth-sized interferometer – released the first direct image of a black hole. The landmark result, […]

It is 30 years since Tim Berners-Lee, while working at CERN, released his proposal for a new information-management system. Two years and a lot of coding later, this vision of universal connectivity had become the […]

The study of the production of quarkonia, the bound states of heavy quark–antiquark pairs, is an important goal of the ALICE physics programme. The quarkonium yield is suppressed in heavy-ion collisions when compared with proton–proton […]

The fundamental structure of nucleons is described by the properties and dynamics of their constituent quarks and gluons, as described by QCD. The gluon’s self-interaction complicates this picture considerably. Non-linear recombination reactions, where two gluons […]

The Standard Model (SM) allows neutral flavoured mesons such as the D0 to oscillate into their antiparticles. Having first observed this process in 2012, the LHCb collaboration has recently made some of the world’s most […]

Precision measurements of diboson processes at the LHC are powerful probes of the gauge structure of the Standard Model at the multi-TeV energy scale. Among the most interesting directions in the diboson physics programme is […]

On 16 June 2018, a bright burst of light was observed by the Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in Hawaii, which automatically searches for optical transient events. The event, which received the automated […]

NOvA joins supernova watch The NOvA experiment in the US, designed to study neutrino oscillations in a beam produced at Fermilab, has joined the Supernova Early Warning System (SNEWS). SNEWS is a global network of […]

The High-Luminosity LHC (HL-LHC), scheduled to operate from 2026, will increase the instantaneous luminosity of the LHC by at least a factor of five beyond its initial design luminosity. The analysis of a fraction of […]

On 18 February the CMS and MoEDAL collaborations at CERN signed an agreement that will see a 6 m-long section of the CMS beam pipe cut into pieces and fed into a SQUID in the name […]

Newly published results from the MINOS+ experiment at Fermilab in the US cast fresh doubts on the existence of the sterile neutrino – a hypothetical fourth neutrino flavour that would constitute physics beyond the Standard […]

Ideas from supersymmetry have been used to address a longstanding challenge in optics – how to suppress unwanted spatial modes that limit the beam quality of high-power lasers. Mercedeh Khajavikhan at the University of Central […]

It is 20 years since the discovery that the expansion of the universe is accelerating, yet physicists still know precious little about the underlying cause. In a classical universe with no quantum effects, the cosmic […]

The electromagnetic field of the highly charged lead ions in the LHC beams provides a very intense flux of high-energy quasi-real photons that can be used to probe the structure of the proton in lead–proton […]