Experimental Flavor Physics

University Of Cincinnati Main Campus, Cincinnati OH

Investigators

Abstract

One of the major intellectual achievements of the 20th century was the development of the Standard Model (SM) of particle physics. This model succeeded in classifying all of the elementary particles known at the time into a hierarchy of groups having similar quantum properties. The validity of this model to date was recently confirmed by the discovery of the Higgs boson at the Large Hadron Collider (LHC) at the CERN laboratory near Geneva, Switzerland. However, the Standard Model as it currently exists, leaves open many questions about the universe. These include why matter dominates over anti-matter in the Universe (CP violation), the values of the masses of the fundamental constituents of matter, the quarks and the leptons, the size of the mixings among the quarks, and separately among the leptons, and the properties of dark matter. Most explanations require the presence of new forces and the development of concepts that now constitute what we call physics Beyond the Standard Model (BSM). This award supports research that addresses those questions that dominate BSM physics. The research will be carried out at the LHC, which is the premier High Energy Physics particle accelerator in the world and one of the foremost facilities for answering these BSM questions. LHCb is the first experiment designed specifically to study the decays of hadrons containing b or c quarks at a hadron collider. The goal of LHCb is to identify new physics in nature by examining the properties of hadrons containing these quarks. New physics, or new forces, are manifest by particles, as yet to be discovered, which would modify decay rates and CP violating asymmetries, and thus allow new phenomena to be observed indirectly. In direct searches for new particles, the accelerator's energy must be high enough to allow the particle to be produced. In indirect searches effects of new particles can be seen even if they have a much higher mass than can be seen directly, because the effects are quantum in nature, and appear in Feynman diagrams where the particles are" virtual", so they are emitted and absorbed over short times. LHCb has operated very successfully starting in late 2010. This award will allow the study of rare decays of heavy quark systems. These decays provide a unique window into physics at an energy scale well beyond that accessible by explicit production of new particles at colliders. This is increasingly important as the limits for new physics by CMS and ATLAS increase, the only window may turn out to be in the studies of rare decays. This work will concentrate mostly on charm quark physics, the expertise of the group. These charm channels can show BSM physics in CP violation and other parity violating asymmetries. Any discovery of BSM physics would be a huge step forward in our understanding of the fundamental physics of the universe. In addition, this award will facilitate a small part of the ongoing LHCb detector upgrade that will improve the overall ability of the detector to fully exploit the LHC data.