Joseph Dwyer

Joseph R. Dwyer (born 1963) is an American physicist known for his lightning research. He is a professor of physics at the University of New Hampshire. Dwyer received his Ph.D. in physics from the University of Chicago in 1994 and worked on cosmic-ray physics and gamma-ray astronomy as a research scientist at Columbia University and the University of Maryland before joining the faculty at the Florida Institute of Technology in 2000. After moving to Melbourne, Florida, Dwyer became interested in lightning physics and his research now focuses on high-energy radiation production from thunderstorms and lightning. In 2002, Dwyer and collaborators discovered that rocket-triggered lightning produced large quantities of x-rays, allowing for first the time detailed studies of an atmospheric phenomenon known as runaway breakdown. In 2014, Dwyer left the Florida Institute of Technology and joined the University of New Hampshire. Research In 2002 Dwyer, along with colleagues from Florida Institute of Technology and the University of Florida, launched rockets during thunderstorms at a facility now known as the UF/Florida Tech International Center for Lightning Research and Testing (ICLRT) at Camp Blanding, Florida. Using a heavily shielded instrument containing a scintillation detector, built by Dwyer and his students, they found that lightning does indeed produce x-rays and that x-ray emission is common for lightning. This research was published in Science (Dwyer et al. 2003). Since that time, Dwyer and his collaborators have established many key properties of the x-ray emissions from lightning, including the fact that the x-ray emission is produced during the lightning stepping process, has energies up to approximately 1 MeV and the x-rays are produced in the high field regions generated by the leader as it propagates. In 2005 TERA (Thunderstorm Energetic Radiation Array), a 24 detector array, was built to continue measuring x-rays and gamma-rays from lightning and to further study the x-ray characteristics that are associated with thunderstorms. Also, in 2005, Dwyer and collaborators made the surprising discovery that long laboratory sparks in air also generate x-rays similar to lightning, which has since motivated many groups around the world to study the x-ray emissions from sparks. Most recently, Dwyer and his team have built and deployed an x-ray camera at the ICLRT and have made the world's first x-ray images of lightning.