Department of Physics & Astronomy, Brigham Young University, Provo, Utah, United States of America.|Department of Physics & Astronomy, Brigham Young University, Provo, Utah, United States of America.|Department of Biostatistics, UT MD Anderson Cancer Center, Houston, Texas, United States of America.|Department of Experimental Radiation Oncology, UT MD Anderson Cancer Center, Houston, Texas, United States of America.|Department of Experimental Radiation Oncology, UT MD Anderson Cancer Center, Houston, Texas, United States of America.|Department of Physics & Astronomy, Brigham Young University, Provo, Utah, United States of America.