Searching for Physics Beyond the Standard Model at the LHCb Experiment

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

The search for new fundamental interactions of nature is at the heart of experimental particle physics. The current Standard Model of particle physics has been enormously successful at describing current measurements, but it is an incomplete theory. All of the experiments at the Large Hadron Collider (LHC) operating at CERN near Geneva, Switzerland are focused on discoveries beyond the Standard Model. This project and the LHCb experiment as a whole seek new discoveries through precision measurements of particle decays produced at the LHC. These measurements aim to answer questions stretching back to the Big Bang, such as, why is our universe dominated by matter and not antimatter? Or what is Dark Matter? The existence of dark matter has been inferred from the effects of its gravitational interactions; however, little is known about the dark sector itself. The possibility that dark matter may interact via as-yet-unknown forces has motivated a dedicated worldwide effort to search for these interactions. Discovering and characterizing dark matter particles and their interactions is vital to advancing scientific understanding of the fundamental nature of the universe and the work from this award could make a break-through discovery at the LHCb experiment. Many compelling dark-sector force scenarios predict the existence of particles that could be observed at the LHCb experiment at the Large Hadron Collider (LHC) at CERN, such as the so-called hidden-sector theories. These theories predict a mixing between dark matter and the Standard Model particles such as the dark photon. Discovering such particles would provide humankind with its first window into the particle nature of the dark sector. This grant supports pioneering work focused on searching for dark-sector forces and dark-matter particles at LHCb. The focus will be on particular decays of B quarks, which the LHCb experiment was designed to measure, that have enhanced sensitivity to dark particles because of the decay channels involving b quark to s quark transition.