The LHC experiments ATLAS, CMS, ALICE and LHCb presented new results from the LHC’s first run, which concluded in 2013. For ATLAS and CMS, the run-1 Brout-Englert-Higgs (BEH) analyses are reaching a conclusion and all show that the Higgs particle behaves in a way consistent with the Standard Model: the theory that accounts for the behavior of fundamental particles of matter and the interactions at work between them.
The Standard Model describes the behavior of what we consider to be ordinary matter to great precision, but we know that ordinary matter makes up just about 5% of the total matter and energy of the Universe: there’s much more to be discovered in the so-called dark Universe of Dark Matter and Energy.
Supersymmetry is a gigantic field for theoreticians so now proponents are reworking Dark Matter, which predicts a range of so-far unobserved particles that could make up the 27% of the Universe, to fit that hypothesis. Through run-1, the LHC experiments have ruled out most supersymmetric models, and more possibilities will be excluded or remain in run-2. Based on the run-1 sample, the BEH analyses do not rule out new physics, and with a much higher Higgs production rate at higher energy in run-2, there is still hope for supersymmetry.
Spearheaded by the ALICE experiment, which is dedicated to exploring Quark Gluon Plasma (QGP), the hot-dense state of matter that would have existed just after the Big Bang, all the LHC experiments have delivered new insights into this exotic form of matter. And LHCb, the experiment that specializes in measuring short-lived particles with great precision, presented a range of results showing the power of the LHCb detector in contributing to a wide range of topics, from QGP to matter-antimatter asymmetry.
After 18 months of maintenance and upgrading, the CERN accelerator complex is now starting up for physics.
“The LHC is a focal point for particle physics research at the high-energy frontier,” said CERN Director General Rolf Heuer. “It forms part of globally coordinated strategy for the field, with plans in Europe, North America and Japan converging to ensure strength in the field in all regions.”