Beyond the Standard Model in the Electroweak Sector with Tau Leptons

University Of Washington, Seattle WA

Investigators

Abstract

This award will provide support for work on the ATLAS experiment at the Large Hadron Collider (LHC) at CERN, a particle physics laboratory in Geneva, Switzerland. The LHC machine and ATLAS, a large particle detector facility, were built as basic science tools using funds from NSF and other agencies around the world. The 2012 discovery, at the LHC, of a Higgs boson with mass close to 125 GeV represents both the crowning achievement of the Standard Model of particle physics and a hint beyond it - how can a light Higgs boson possibly survive huge, destabilizing quantum effects without new, undiscovered physics? The next step in the experiments is to look for evidence for physics Beyond the Standard Model (BSM) that might, for instance, account for the presence of the mysterious "Dark Matter" that makes up so much of the mass of the universe. The LHC is currently just starting a new phase, Run 2, at higher energy and increased event samples. It is possible that evidence for BSM physics could emerge in the next couple of years. This award will provide tools for detecting new BSM physics through searches for Higgs decaying to heavy tau leptons. Taus can only be seen through the decay products which themselves are difficult to detect. The PI will apply new machine learning techniques to extract these Higgs decays which have a large momentum transfer from the colliding protons. This class of Higgs is especially sensitive to contributions to new BSM particles. The proposed studies also have the potential to further improve the capabilities of the ATLAS detector to detect hadronic decays of the τ lepton. The broader impacts of this award will be in outreach activities in local Seattle high schools. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.