Baseline Support for the University of Utah Cosmic Ray Physics Group including Telescope Array Analysis

University Of Utah, Salt Lake City UT

Investigators

Abstract

The nature of cosmic ray sources and the mechanisms that accelerate cosmic rays to ultrahigh energies are among the most important questions in astrophysics. Answering these questions involves measurements of the energy spectrum and composition of cosmic rays as well as searches for anisotropy in their arrival directions as a direct way of identifying sources. The University of Utah Cosmic Ray Physics Group has primary responsibility for the Telescope Array (TA), which is the largest detector for ultrahigh energy cosmic rays in the northern hemisphere. With this award the University of Utah Cosmic Ray Group will continue to collect and analyze the data from TA and the TA Low Energy Extension (TALE) with the goal of addressing these astrophysics questions. Their main education and outreach activity is the ASPIRE Project, which creates and maintains interactive science lessons and labs on the web. ASPIRE also provides direct outreach to area teachers, runs summer workshops for students, and makes visits to rural schools. The Lon and Mary Watson Cosmic Ray Center in Delta, Utah, is the center of TA outreach work, and of field operations. The building includes a visitor's center, with TA exhibits, including a real-time detector display. The University of Utah Cosmic Ray Physics Group has a long history of studying the spectrum, composition, and sources of the highest energy particles in the universe. The coming three-year award period should see important developments with increased statistics, access to lower energy data, and improved analysis and coordination. The Utah group is studying the ultrahigh energy cosmic ray spectrum in detail to the low energies available through TALE, pursuing possible correlations with the large scale structure to refine TA composition measurements, and studying evidence of anisotropy to search for the sources of cosmic rays. In addition, the group is working with the Pierre Auger collaboration to understand differences in composition measurements between the two experiments.