Bruce departed Tonopah this morning for Bishop. Shane on site.
Decided to leave the REAL operating last night to observe the stability of the laser transmitter. Weather conditions were very clear and I suspect there may not have been much happening in terms of aerosol activity. However, it was a good opportunity to record the performance of the transmitter with no interruptions with a fresh set of flashlamps. The changes on the left side of the following graphs are associated with activities yesterday. Please see the August 27 write up for a discussion. Overall, we can see the pump power (1064 nm) decreased a little bit (from 535 mJ to 523 mJ) and the 1543 nm pulse energy has been decreasing slightly also (from 138 mJ to 124 mJ). Scott Spuler suggests increasing the q-switch delay by 5 microseconds if the 1543 nm pulse energy drops below 120 mJ.
Checking on the transmitter today. Since electronic pressure measurements of the Raman cell are not working, we periodically take photos of the mechanical gage, and today it looks normal as it has since March.
Inspection of the 2" mirror downstream of the Raman cell to see if there is any additional damage:
No apparent additional damage since yesterday.
Below: 1:55 PM PDT eastern panorama.
Here is the GOES visible satellite image from 2 PM PDT and this mornings 500 mb chart:
During the last couple of days, REAL can typically detect the signal from this very weak background aerosol to ranges of 1.5 to 2.0 km. However, if an aerosol feature (a deviation from the background, for example caused by a source of PM or a gust that lifts PM from the surface) then it can easily see that to much longer ranges.
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Unknown User (shane)
Monday, August 28
Bruce departed Tonopah this morning for Bishop. Shane on site.
Decided to leave the REAL operating last night to observe the stability of the laser transmitter. Weather conditions were very clear and I suspect there may not have been much happening in terms of aerosol activity. However, it was a good opportunity to record the performance of the transmitter with no interruptions with a fresh set of flashlamps. The changes on the left side of the following graphs are associated with activities yesterday. Please see the August 27 write up for a discussion. Overall, we can see the pump power (1064 nm) decreased a little bit (from 535 mJ to 523 mJ) and the 1543 nm pulse energy has been decreasing slightly also (from 138 mJ to 124 mJ). Scott Spuler suggests increasing the q-switch delay by 5 microseconds if the 1543 nm pulse energy drops below 120 mJ.
Checking on the transmitter today. Since electronic pressure measurements of the Raman cell are not working, we periodically take photos of the mechanical gage, and today it looks normal as it has since March.
Inspection of the 2" mirror downstream of the Raman cell to see if there is any additional damage:
No apparent additional damage since yesterday.
Below: 1:55 PM PDT eastern panorama.
Here is the GOES visible satellite image from 2 PM PDT and this mornings 500 mb chart:
During the last couple of days, REAL can typically detect the signal from this very weak background aerosol to ranges of 1.5 to 2.0 km. However, if an aerosol feature (a deviation from the background, for example caused by a source of PM or a gust that lifts PM from the surface) then it can easily see that to much longer ranges.