NSA/HSRL/C1 - Degraded operation, laser instability, dirty window

Following installation instrument was still not operating optimally.  Laser instability 
and reduced sensitivity were impacting measurements.  Cleaning of the external window 
improved signal levels and sensitivity on March 18 17:30.

The height of detected clouds and aerosols is quantitative and accurate however the 
calibrated backscatter quantities are uncertain.  Nevertheless, the sensitivity of the HSRL 
even in this degraded capacity is superior to VCeil and MPL for cloud and aerosol detection.

• Particulate backscatter cross section per unit volume(beta_a_backscatter)
• Particulate extinction cross section per unit volume(beta_a)
• Circular depolarization ratio for particulate(depol)