Experimental Particle Physics

University Of New Mexico, Albuquerque NM

Investigators

Abstract

Data from the ATLAS Experiment at the Large Hadron Collider are being collected and analyzed in a search for phenomena that have not been observed before; this is a Search for New Physics Beyond the Standard Model. The new phenomena may revolve around characteristics of the bottom quark, one of the fundamental building blocks of nature, and cast light on the question of why antimatter is virtually absent from our universe. The ATLAS data are applied to a measurement of the branching ratios of B0 and Bs0 decays to two muons in the full Run 2 LHC dataset to explore a tension with Standard Model predictions that earlier data suggested. The ATLAS data are also applied to a measurement of CP-violation parameters in decays of the Bs0 meson to the J/psi phi state. A first ATLAS measurement of the partial branching fraction of B0 mesons to Kshort and two muons is also underway, as the high statistics available can bring clarity to the realm of b-quark to s-quark transitions where a variety of tensions with the Standard Model have been reported. Analysis of these data is supported by performance studies that ensure optimal alignment of the ATLAS tracking system and optimal operation of the Pixel detector. Studies to improve data collection and analysis strategy in future experimental runs are also underway, as are activities such as technical reviews of manuscripts and presentations and service as an analysis group convener. Parts of the effort involves development of machine learning strategies that, if migrated into the wider world, can contribute to prosperity and security in accordance with the NSF mission. Graduate students and postdocs are being trained in advanced technical and analytical skills, and results are being shared with teachers, school groups, and the wider 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.