Phys.org July 1, 2020 Researchers at CERN led by UK scientists found the new tetraquark using the particle-hunting technique of looking for an excess of collision events called bumps, over a smooth background of events. The bump has a statistical significance of more than five standard deviations, the usual threshold for claiming the discovery of a new particle, and it corresponds to a mass at which particles composed of four charm quarks are predicted to exist. As with previous tetraquark discoveries, it is not completely clear whether the new particle is a “true tetraquark”, that is, a system of four […]
Tag Archives: CERN
Light can scatter from light, CERN physicists confirm
Physics World August 14, 2019 The quantum electrodynamic process of photon–photon scattering has for the first time been confirmed experimentally to a high degree of certainty. CERN’s ATLAS collaboration, which involves hundreds of physicists from around the world, made the breakthrough after analysing a large dataset of candidate scattering events using a neural network. Their discovery could fuel new research into a variety of theories beyond the Standard Model of particle physics. The discoveries of the ATLAS collaboration could inform future studies aiming to confirm and constrain these theories, potentially allowing much-anticipated updates to the Standard Model…read more. Open Access […]