Event display for a potential SUEP event, recorded at CMS in 2018, showing the characteristically high multiplicity of soft tracks in yellow. Could there be a “dark world“ composed of invisible particles held together by a new strong dark force,…
Neutron stars, ultra-cold atomic gasses, and the quark-gluon plasma… You may find them totally unrelated but, surprisingly enough, they share a common feature: a fluid-like state of matter containing strongly interacting particles! An insight into…
A proton-proton collision at a centre-of-mass energy of 13 TeV, recorded by CMS, compatible with the production of a Higgs boson decaying to a J/ψ meson, which decays to two muons (red lines), and a high-energy photon (green box, top). Try to zoom…
The universe is governed by four known fundamental forces: gravity, electromagnetism, the weak force, and the strong force. The strong force is responsible for dynamics on an extremely small scale, within and between the individual nucleons of…
The main goal of the LHC physics programme is to deeply understand the fundamental principles of particles and their interactions. As part of this quest, physicists are searching for evidence of new particles, which would potentially confirm the…
Imagine diving into the very core of the universe, where the tiniest pieces that make up everything hold the answers to big cosmic questions. Leading this exciting journey is the CMS team at the Large Hadron Collider (LHC). We are on a mission to…
  The more collisions the better, right? To search for new physics, the aim of the LHC experiments at CERN is to collect and investigate as many proton-proton collisions as possible to increase the chances that undiscovered particles are created and…
Two key properties of neutrinos in the standard model of particle physics (SM) are that they are massless and “left-handed”, i.e. their spin is always opposite to their momentum. The observation of neutrino oscillations posed a big challenge to the…
The first search for new physics using LHC data collected in Run 3 has been presented by CMS. It was shown during this year’s EPS conference in Hamburg and relied on both the new data and refinements of the trigger system made for Run 3. It marks…
At the subatomic level, interactions between particles are mediated through the exchange of special particles, the force carriers. In the case of electromagnetism, the force is transmitted by photons. They connect particles with electric charge (…
It is easy to recognize your friends in a street if they are standing or walking, but what if they are riding a supercar at a speed of 150 km per hour? In the Large Hadron Collider, if the energy of two partons from two colliding protons is about…
Among all the elementary particles, quarks and gluons (partons) are the only ones that cannot be observed in isolation. In high-energy collisions, such as those occurring at the Large Hadron Collider (LHC), partons undergo a few stages between their…