Description


Page : 1950

Sondrestrom Lidar Operation Log


Operator(s) : J Thayer
Purpose : Testing Big sky laser
Date(s) : 080510 - 080511
File(s) : L20080510_001 - L20080511_001
Comments : Studying the Big Sky and Rayleigh signal behavior under different configurations

Reference timing of laser 1 and 2 is same as last night. Presently Laser 1 is
functioning and laser 2 is down
Logfile : l0805101.log

Setup:0


Page : 1951
[0]
front end Iris=not_installed
Rayleigh System=On
Rayleigh Field stop=4.0mm
Rayleigh path attenuation=0dB
Dye System=On
Sodium Field stop=0.5mm
Etalon=Out
Daystar=Out
Polarizer=In
HalfWave Plates=Tracking
Rayleigh Filter=2:532(.5nm)
Rayleigh seeding=off

Logsheet:0


Page : 1952

Sondrestrom Lidar Operation Log


Log Sheet 1 of 3
Operators : J Thayer
Date(s) : 080510 - 080511
File(s) : L20080510_001 - L20080510_001
FilesTime [UT]CommentsCntSOpe
L20080510_00123:39:11Start of experiment-72960
Starting with just background - no Daystar and iris position
at prime focus is about 2mm open. Second iris is about
5mm open
23:45:04put Daystar in place-23110
23:48:41clear skies by the way-2630
23:58:44added a 20dB ND filter - improved the chopper shape-2070
on the closing portion - I suspect SIN due to high bkgrnd
00:04:53took out 20 dB ND and placed a 3 dB ND - looks like the 0
SIN is back-138
L20080510_00100:11:08added another 3dB ND to make it 6dB - SIN is still present0
must look for this signature when running regularly
00:58:47started laser 1 about 40 minutes ago but had trouble0
with scope now it is converged
I also stopped HW plate tracking 40 minutes ago by
unplugging the motorized mount
01:04:01set the Rx HW plate to minimize laser 1 signal0
Daystar and 6 dB ND still in path
01:10:13removed 6dB NDs only Daystar now-140
backgrnd is lower and some weak SIN in data
01:16:21Daystar removed - also Rx cover has been on since 23:450
01:17:43Backgrnd signal stronger and SIN is certainly noticeable0
in closing portion of chopper window
01:24:30no noticeable SIN above laser 10

Logsheet:1


Page : 1953

Sondrestrom Lidar Operation Log


Log Sheet 2 of 3
Operators : J Thayer
Date(s) : 080511 - 080511
File(s) : L20080510_001 - L20080510_001
FilesTime [UT]CommentsCntSOpe
L20080510_00101:26:21Rotated Rx HW plate 45 degrees to maximize laser 10
SIN noticeable in top portion of signal as it meets the
background
L20080510_00101:39:38Put Daystar back in 0
Looks like that eliminated most of the SIN caused by laser 1
some SIN still in closing portion of chopper. Will try to
iris at prime focus
L20080510_00101:49:27reduced prime focus iris-460
removed most SIN in closing portion of chopper
01:57:30moved chopper window down so I can see it open before0
laser 1 signal changed setting from 39 to 19 on dial
02:09:04reduced laser energy from 10 to 5 on power suppply0
02:18:02reduced power to level 4 any lower and the laser energy0
is unstable
02:26:03full power (level 10) and raised chopper to dial position 290
02:32:51firing laser 2 now - intermittent pulsing just want reference0
position
02:35:21moved chopper up to original position 390
02:41:40turned off laser 20
02:47:44turned on Rayleigh laser will need to converge and 0
optimize polarization
03:13:45Rayleigh seems a bit low and chopper function is not as sharp0
also could not reduce the second iris below 6mm
may need to adjust but will leave for now

Logsheet:2


Page : 1954

Sondrestrom Lidar Operation Log


Log Sheet 3 of 3
Operators : J Thayer
Date(s) : 080511 - 080511
File(s) : L20080511_000 - L20080511_001
FilesTime [UT]CommentsCntSOpe
L20080511_00003:15:02near local midnight - removed Daystar and will take3570
data for a while
L20080511_00003:43:11Nice clear night the entire time0
L20080511_00003:45:08by the way, adjusted HW plate and plugged in chopper0
at 03:15 so should be tracking
L20080511_00004:18:22Rayleigh signal is still looking good so let's keep the Dstar out4040
05:30:58got a GPIB error message but checked SR430 and seems fine0
data continues to be recorded
L20080511_00105:53:06remains nice and clear but sun coming up0
05:57:12can see SIN in closing portoin of chopper window due to0
inc background
05:59:43Daystar has been placed in the path270
much improved profile looks like SIN was happening before
Daystar went in
L20080511_00106:31:31too much sunlight sza =88 0
L20080511_00106:32:04End of experiment0