4 papers
Similarities in the Initiation of Upward Positive and Downward Negative Lightning Flashes
Toma Oregel-Chaumont, Mohammad Azadifar, Antonio Å unjerga +2
This study examines the relationship between upward negative stepped leader pulses in upward positive lightning and preliminary breakdown pulses (PBPs) in downward negative lightni…
Underlying Physical Mechanisms in Upward Positive Flashes
Toma Oregel-Chaumont, Antonio Šunjerga, Jérôme Kasparian +2
This study presents the first observation of a mixed mode of charge transfer during an upward positive flash, which was initiated from the Säntis Tower in Switzerland. High-speed…
Cartesian and spherical multipole expansions in anisotropic media
Elias Le Boudec, Toma Oregel-Chaumont, Farhad Rachidi +2
The multipole expansion can be formulated in spherical and Cartesian coordinates. By constructing an explicit map linking both formulations in isotropic media, we discover a lack o…
Does light slowdown in dielectric media?
Vernon Cooray, Gerald Cooray, Farhad Rachidi +1
Observations and theoretical principles suggest that electromagnetic waves, including light, travel more slowly in dielectric media than in vacuum. Maxwell's equations, incorporati…