LIP is member of the Compact Muon Solenoid (CMS) Collaboration at the Large Hadron Collider (LHC) at CERN since 1992. The scientific motivations of the research at the LHC are at the heart of our quest for understanding the fundamental physics laws of the universe. The LHC has collided proton beams at 7 and 8 TeV in 2011-12. In general the performance of the LHC machine and of the detectors has been outstanding. The LHC has delivered an integrated luminosity of about 25 fb-1. A wide range of measurements was undertaken (resulting in about 390 publications). All results appear to be compatible with the predictions of the Standard Model. In 2012 the LHC community achieved a major discovery with profound consequences in particle physics. The ATLAS and CMS experiments observed a new heavy particle with a mass of 125 GeV, compatible with the Higgs boson. The LIP/CMS group is proud to have been a full partner of this achievement, through the scientific work developed consistently in the past twenty years. In 2013-14 a long LHC shutdown permitted the upgrade of the collider to a center-of-mass energy of 13 TeV and instantaneous luminosity of 1034 cm2 s-1 and above. These operating conditions will bring new opportunities for physics discoveries but also additional challenges for the CMS detector operation. The LIP/CMS group has been active in many areas of the CMS experiment having contributed significantly to all phases of its long trajectory. The main LIP responsibilities in the construction of the CMS Experiment were the following: * Design and construction of the Data Acquisition System of one of the major CMS sub-detectors, namely the Electromagnetic Calorimeter (ECAL) used for the measurement of electrons and photons; * Study, design, construction, installation and commissioning of the Trigger System responsible for the first level of event selection. In the CMS physics program, the LIP/CMS group made major scientific contributions in the following areas: * the discovery of a Higgs boson in the two-photons decay channel; * the study of the Higgs properties, including the measurement of the Higgs couplings; * the measurement of the top quark mass, a fundamental parameter of the Standard Model; * the measurement of the Vtb element of the CKM matrix, by studying the decays of the top quark; * the measurement of the J/Psi(nS) e Υ(nS) production polarizations in pp collisions; * the search for a light/heavy charged Higgs decaying from/to the top quark; * the search for the supersymmetric partner of the top quark.

Photos

Site do Grupo no LIP

Contacts

Group Leader:  

João Varela

Joao.Varela@cern.ch