Research Presentation, Xing Wu

Title:
Where is All the Antimatter? Electron EDM Search in Cold Molecules Edges Closer

Abstract:
The Standard Model of particle physics accurately describes all fundamental particles discovered so far.
However, it is unable to address two great mysteries in physics, the nature of dark matter and why
matter dominates over antimatter throughout the Universe. Novel theories beyond the Standard Model,
such as models that incorporate supersymmetry, may explain these phenomena. These models predict
very massive particles whose interactions violate time-reversal (T) symmetry and would give rise to an
electric dipole moment (EDM) along the electron’s spin. Thus, searching for EDM provides a powerful
probe to these new physics and sheds light on the mystery of the matter-antimatter asymmetry of the
Universe. Here, I share with you the exciting journey of the ACME electron EDM search that has set the
current best limit on the value of electron EDM, measured by spin precession in a superposition of
quantum states in cold molecules. This result severely constrains T-violating new physics in 330 TeV
energy range, exceeding what can be reached at the Large Hadron Collider. New upgrades are now
underway, projecting over an order of magnitude sensitivity enhancement for the next EDM search.