Design and construction of a cosmic ray detector array for the correlation of cosmic ray extensive air showers with lightning strikes

The process of lightning initiation is a poorly understood phenomenon. One contending theory suggests that galactic cosmic rays play a role in initiating lightning. This theory is referred to as runaway breakdown (RB). Currently there is no known experimental evidence to support RB. For this thesis, a cosmic ray detector array was designed, constructed, and calibrated in order to gather data to test the RB theory. The goal is to correlate cosmic ray extensive air showers (EAS) with lightning strikes measured by the Oklahoma Lightning Mapping Array (OKLMA). Such a correlation would serve as strong experimental evidence that EAS play an important role in lightning initiation. In order to accomplish this goal, the cosmic ray detectors need to have fast timing for high resolution and be able to distinguish between the secondary hard component (muons) and soft component (electrons/gamma rays) of the EAS. Preliminary data from the detector testing site suggests that the detectors are operating according to the design goals. They are able to resolve individual muon counts and they have measured common phenomena such as radon washout and EAS diurnal variation.