Colloquium
Here is the schedule for Fall 2025
Previous abstracts of colloquia from this semester will be archived as the semester progresses.
Seminars are held on Thursdays at 4 PM in Workman 101
October 2, 2025 Colloquium:
Speaker: Dr. Mike Stock
Affiliation: Cooperative Institute for Severe and High-Impact Weather Research and
Operations (CIWRO), University of Oklahoma, Norman, Oklahoma and NOAA/OAR National Severe Storms Laboratory (NSSL), Norman, Oklahoma.Lightning interferometry with the Long Wavelength Array
Interferometers have revealed much of the detailed behavior and physics we know about lightning flashes today. But, most of the interferometers used to study lightning only have a very small number of elements, frequently just 3 antennas. Much of this ultimately has to do with cost; lightning interferometers record about 400 MB/s/channel in the system, and equipment that can handle the bandwidth of more than 4 channels gets prohibitively expensive. On the other hand, several astronomical interferometers with more than 3 or 4 antennas exist today. Unfortunately, some of the design choices made in these radio telescopes are not well suited to lightning observations. Unlike celestial bodies, lightning does not radiate from a predictable location, nor for a long period of time. Instead, it鈥檚 a very transient event that radiates from multiple widely spaced locations moving across the sky at (nearly) the same time. In this presentation, we鈥檒l go over how to use the LWA to make observations of lightning. This includes what the data look like, how to turn the records into dirty images with sub-microsecond resolution, and some simple methods of deconvolving the images. Then we鈥檒l look at some results from a handful of example flashes to show off the capabilities of the instrument.