Affiliation: | 1. School of Physics Astronomy and Computational Science, George Mason University, Fairfax, VA 22020, USA;2. Heliospheric Science Laboratory, Code 672, Goddard Space Flight Center, Greenbelt, MD 20771, USA;3. Center for Atmospheric Research, University of Massachusetts, Lowell, MA 01854, USA;4. Lowell Digisonde International, LLC, Lowell, MA 01854, USA |