Ball lightning observation: an objective video-camera analysis report
  In this paper we describe a video-camera recording of a (probable) ball lightning event and both the related image and signal analyses for its photometric and dynamical characterization. The results strongly support the BL nature of the recorded luminous ball object and allow the researchers to have an objective and unique video document of a possible BL event for further analyses. Some general evaluations of the obtained results considering the proposed ball lightning models conclude the paper. 
Stefano Sello, Paolo Viviani and Enrico Paganini
physics.gen-ph physics.class-ph