Methods to Quantify Aerosol Absorption That Could Cause Laser Thermal Blooming

Hosted By: Laser Systems Technical Group

13 October 2021, 13:00 - 14:00 - Eastern Daylight Time (UTC - 04:00)

Atmospheric absorption at typical laser wavelengths has both molecular and aerosol components, especially in near-surface (land or maritime) environments. At some wavelengths and laser powers, the heating of the air by aerosol absorption can be greater than heating by molecular absorption, even when continuum molecular absorption is considered. The real and imaginary parts of the refractive index of various aerosol substances have been tabulated in the literature as a function of wavelength and have been incorporated into some field validated atmospheric characterization / radiative transfer codes and laser propagation codes, which suggest some simple methodologies for quantifying naturally occurring aerosol absorption that can cause heating of air due to laser propagation.

In this webinar hosted by the Laser Systems Technical Group, Steven Fiorino from the Air Force Institute of Technology will outline a simple, low-cost method to rapidly quantify aerosol and molecular absorption and scattering effects at any laser wavelength using only measurements of temperature, pressure, humidity, and aerosol number concentration.

Subject Matter Level: Intermediate - Assumes basic knowledge of the topic

What You Will Learn:

  • Measure/quantify heating of air due to laser absorption by naturally occurring aerosols
  • Demonstrate that quantifying thermal blooming effects (distortion and displacement of the beam) may be a viable way to directly measure bulk aerosol absorption properties using a high-energy laser

Who Should Attend:

  • Those who are interested in methods to quantifiably separate the bulk aerosol scattering and absorption effects of naturally occurring aerosol distributions.

About the Presenter: Steven Fiorino, Air Force Institute of Technology

Dr. Steven T. Fiorino is a Professor of Atmospheric Physics in the Department of Engineering Physics, Graduate School of Engineering and Management, Air Force Institute of Technology (AFIT) at Wright-Patterson AFB, Ohio. Currently, he is Director of AFIT’s Center for Directed Energy. Dr. Fiorino’s research interests include microwave remote sensing of the environment, development of weather signal processing algorithms, and atmospheric effects on military systems such as high-energy lasers and weapons of mass destruction.