Laser-triggered lightning laboratory tests: Preparation for testing at Mississippi State University High-Voltage Laboratory. Interim report

Technical Report · Mon Dec 01 04:00:00 EST 1997

OSTI ID:355057

Diels, J C ^[1]

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1. Univ. of New Mexico, Albuquerque, NM (United States)

The project`s long term objective is to trigger lightning with ultrashort and intense, ionizing ultraviolet laser pulses, combined with longer pulses to maintain the channel conductivity until the discharge is established. There are numerous related problems to be solved to reach the ultimate goal, each of them constituting a scientific problem of its own. The main problems fall under the category of pulse propagation effect, multiphoton ionization (seeding of electrons), maintaining a conductive channel, and plasma (discharge) formation. Particular attention has to be given to the beam quality (spatial profile) and pulse to pulse reproducibility, in order to control the nonlinear effects associated with the propagation through air of these intense pulses. A large laboratory laser, with associated monitoring systems has been built to study the discharge over 1/4 m. Pulses of 15 mJ energy, 100 fs duration at 248 nm are being generated at a repetition rate of 10 Hz. Associated diagnostic instruments have been designed and constructed, including a single shot autocorrelator to measure the duration of visible pulses, an instrument to measure the amplitude and phase of these pulses, and a UV autocorrelator to measure the 248 nm pulses. Measurements of multiphoton ionization cross section are being performed. Techniques to probe the laser induced plasma have been designed to gain a better understanding of the plasma formation. A moveable laser is under construction, based on full solid state technology, in preparation for discharge testing with the 3 MV facility at Mississippi State University. The new laser, to be fitted on a 3.5 m x 65. m table, is expected to provide similar performances as the laboratory laser, at a fraction of the operating costs.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States); Univ. of New Mexico, Albuquerque, NM (United States)
• Sponsoring Organization: Electric Power Research Inst., Palo Alto, CA (United States)
• OSTI ID: 355057
• Report Number(s): EPRI-TR--109754
• Country of Publication: United States
• Language: English

Related Subjects

24 POWER TRANSMISSION AND DISTRIBUTION
LASER RADIATION
LIGHTNING
MISSISSIPPI
MULTI-PHOTON PROCESSES
POWER SYSTEMS
TEST FACILITIES