Description


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Sondrestrom Lidar Operation Log


Operator(s) : Katelynn, Greer, Katelynn Greer
Purpose : Experiments to look at possible power fluctuations
Date(s) : 080717 - 080718
File(s) : L20080717_002 - L20080718_000
Comments : I began this experiment looking for a possible fluctuation in laser energy while the
polarization flipping program is running. I took power measurements for about an
hour. During this time, I saw no oscillations, only a slow decrease in power. I
think this is because of a problem we've been having with a dust tube between the
amplifier and SHG that keeps coming loose and interferring with the beam. After
this experiment, Christian and I tried to use hot glue to keep the tube in place;
hopefully this solution will contine to work. I think I will have to repeat this
particular experiment now that the dust tube has been dealt with, however, since it
is such a boring experiment, I will do this another night. Next, I opened the
PMTs and took data in a single plane of polarization (no flipping, no sun
tracking), for about an hour. Then I changed the plane of polarization and took
about another hour of data. The sky conditions have not been very good. First
there were low puffy clouds and now a high thin (appears to be) cirrus cloud has
been widespread and persistant in the sky for about and hour. The Raman signal
was never very good; the system likely needs to be converged.
Logfile : l0807180.log

Setup:0


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[0]
front end Iris=not_installed
Rayleigh System=On
Rayleigh Field stop=0.5mm
Rayleigh path attenuation=0dB
Dye System=Off
Sodium Field stop=0.5mm
Etalon=In
Daystar=4A_In
Polarizer=In
HalfWave Plates=Tracking
Rayleigh Filter=2:532(.5nm)
Rayleigh seeding=off

Logsheet:0


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Sondrestrom Lidar Operation Log


Log Sheet 1 of 2
Operators : Katelynn Greer
Date(s) : 080717 - 080718
File(s) : L20080717_002 - L20080717_002
FilesTime [UT]CommentsCntSOpe
23:49:37Start of experiment0KRG
Not taking sky data, just examining power fluctuations
Using flipping routine
01:03:40No evident fluctuation in energy determined0KRG
although, there was a steady decline in power from
5300 mJ to 5000 mJ over this period
I think this is due to the dust tube between the ampl and
SGH slipping out of alignment
01:05:20New Experiment where one plane of polarization is held0KRG
for about an hour, then the other for an hour
01:48:59Christian and I have attempted to stabilize the dust tube0KRG
with a bit of hot glue; we will now repeat initial power
measurements
02:08:20SP Power: 5150 mJ0KRG
L20080717_00202:13:40Begin 1/2 plate held at TX offset=49.0, TX pos=49.00KRG
RX offset = 30.0, RX pos = 30.0
Raman PMT power at 0.750
There appears to be a few small thin clouds in the sky
02:17:26380KRG
02:18:34Big Sky Lasers turned on0KRG
02:19:49I am not getting a good Raman profile- I don't know why0KRG
02:29:55I am going to check the placement of the 10 dB0KRG
nuetral density filter that is placed before the chopper
02:36:45Filter position seems fine, still have a poor profile0KRG

Logsheet:1


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Sondrestrom Lidar Operation Log


Log Sheet 2 of 2
Operators : Katelynn Greer
Date(s) : 080718 - 080718
File(s) : L20080717_002 - L20080718_000
FilesTime [UT]CommentsCntSOpe
L20080717_00202:37:16More clouds are beginning to come into view0KRG
02:49:2910KRG
03:08:17Sky conditions are deteriorating10KRG
03:16:49230KRG
L20080718_00003:39:31Switching to new plane of polarization0KRG
RX offset = 30.0; RX pos = 30.0
TX offset = 4.0; TX pos = 49.0
No sun tracking
03:42:24100KRG
03:53:37Outside I see a high thin (appearing) cloud that is spread0KRG
over a large area
04:01:46120KRG
04:06:49Oops, I forgot to turn the Big Sky lasers back on after I0KRG
L20080718_000changed the 1/2 wave plate- they're on now10
04:30:25110KRG
04:46:16I hope I've taken enough good data for Steve to do his 0KRG
analysis, because I'm shutting the system down now
L20080718_00004:46:54End of experiment0KRG