text: # flowfield must contain molecular species with an optical resonance wavelength that can be accessed by laser 
  # temperature measurements typically require two laser sources 
  # velocity measurements typically practical only for high Mach number flows (near sonic or supersonic) 
  # signal-to-noise ratio often limited by detector shot-noise 
  # fluorescence interferences from other species, especially from hydrocarbons in high pressure reacting flows 
  # attenuation of laser sheet across flow field or reabsorption of fluorescence before it reaches detector can lead to systematic errors