Probing 23{\%} of the Universe at the Large Hadron Collider

With recent astronomical measurements, we know that 23{\%} of the Universe is composed of dark matter, whose origin is unknown. Supersymmtery (SUSY), a leading theory in physics, provides us with a cold dark matter candidate, the lightest supersymmetric particle (LSP). SUSY particles, including the LSP, can be created at Large Hadron Collider (LHC) at CERN. We perform a systematic study to characterize the SUSY signals in the ``focus point'' region, one of a few cosmologically-allowed regions in our SUSY model. We also present a methodology for extracting the dark matter signals at the LHC, and show the accuracy to which we can measure the dark matter relic density and the SUSY parameters.