Accelerating Searches for Beyond the Standard Model Physics and the ATLAS Pixel Detector

University Of Washington, Seattle WA

Investigators

Abstract

This award will provide support to a single PI group working on the ATLAS experiment at the Large Hadron Collider (LHC) at CERN, a particle physics laboratory near 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. One of their primary objectives was to find the Higgs Boson, the last particle in the historically successful "Standard Model" (SM) that accounts for so much of the existence of, and forces between, known particles forming the matter in the universe. This effort has been successful. The next step 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 in the midst of analyzing data from Run 2, at almost twice the energy explored earlier and with significantly increased event samples. It is possible that evidence for BSM physics could emerge at this higher energy and with the higher event statistics. Search for evidence of such physics is the goal of this project along with preparation for the next data taking period starting in late 2021.The focus of the BSM search in this award is in discovering the so-called Dark Higgs, one of the possible explanations as to why the Higgs boson has the unexpectedly low mass that it has. There are two main thrusts of the research that will be conducted through this award. The first is developing new analysis techniques, using machine learning, to search for dark Higgs particles in the two-particle decay mode. Machine learning will be used to select out the rare events that could be the dark Higgs. The second is improvements to the CMS detector for the High Luminosity LHC (HL-LHC) upgrade. This work will improve the Pixel detector used to precisely track particles created in the LHC collisions, allowing more precise determination of BSM physics. The award also contains an education and outreach component to engage women undergraduates pursuing STEM careers and promotes teaching, learning, and sharing of the excitement of cutting-edge research with the broader community. 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.