The Compact Muon Solenoid (CMS) Experiment is of a worldwide collaboration of scientists conducting research on the fundamental nature of matter. The experiment is installed at the world’s largest high-energy accelerator, the Large Hadron Collider (LHC) located at CERN, the European Organization for Research in Particle Physics. The CMS group at IPHC has a well-known expertise and also responsibilities in the silicon tracker of the experiment, including the construction of the outer barrel part of the new tracker for the LHC at high luminosity. We are looking for any sign of new physics, beyond the standard model. This research is both indirect (performing high precision measurements, notably on the properties of the Higgs boson, discovered in the experiment in 2012) and direct (searching for new long-lived massive particles). This research on the fundamental subatomic constituents is deeply connected to our understanding of the first moments of the universe.
Scientifique coordinator: Anne-Catherine LE BIHAN
The activities of the CMS team at IPHC are in the following fields :
▪️ Standard Model Physics
The group has long been involved in top quark physics and in the search of new physics using top quark final states. We are now using Z decays into (polarized) tau lepton pairs to measure the electroweak mixing angle.
▪️ Higgs Physics
The group has been one of the contributors for the evidence and observation of the associated production of the Higgs boson with a top-quark pair. We are now involved in the measurement of the CP properties of the Higgs boson in its coupling to tau leptons.
▪️ New physics search
The group was involved in the search of the supersymmetric partner of the top quark. We are now looking for new long-lived massive particles, as predicted in theories beyond the standard model.
▪️ Identification of b quark jets and tau leptons
The group contributes to the tagging of jets from bottom quarks and to the identification of tau leptons which are involved in many physics processes, from top quark and Higgs boson production up to the search for new physics.
▪️ Tracker
After having participated to build the present silicon tracker of the experiment and its electronics, the IPHC group contributes to its monitoring and calibration. We are also deeply involved in the construction of the outer barrel part of the new tracker for the LHC at high luminosity, and we are performing beam tests here at the laboratory on the new silicon modules.
▪️ Computing grid
The IPHC laboratory hosts a Tier 2 of the worldwide LHC computing grid. It provides CPU and disk storage ressources for the CMS and ALICE experiments, as well as for local and regional usage which includes CMS Tier 3, Belle 2, PICSEL group, nuclear physics, bio-informatics, proteomic, etc… More than 3000 slots are provided for computing, amounting to 30M hours per year, and more than 3000 TB of disk storage.
More informations about the Plateforme SCIGNE and LCG-France.
